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Saeedirad Z, Ariyanfar S, Noormohammadi M, Ghorbani Z, Naser Moghadasi A, Shahemi S, Ghanaatgar M, Rezaeimanesh N, Hekmatdoost A, Ghaemi A, Razeghi Jahromi S. Higher Dietary Acid Load Might Be a Potent Derivative Factor for Multiple Sclerosis: The Results from a Case-Control Study. Nutrients 2023; 15:3311. [PMID: 37571248 PMCID: PMC10420939 DOI: 10.3390/nu15153311] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 07/18/2023] [Accepted: 07/18/2023] [Indexed: 08/13/2023] Open
Abstract
This study aimed to investigate the association between dietary acid load (DAL) and multiple sclerosis (MS), through the potential renal acid load (PRAL) and net endogenous acid production (NEAP) scores. In a hospital-based case-control study of 109 patients with MS and 130 healthy individuals, a validated 168-item semi-quantitative food frequency questionnaire and a logistic regression model were used to evaluate the association between the DAL and MS. After adjusting for age (years), gender (male/female), body mass index (Kg/m2), and total calories (Kcal), the MS odds were 92% lower for those in the highest tertile of total plant-based protein (OR: 0.08, 95%CI: 0.03, 0.23; p-value < 0.001) and about four times higher for those in the highest tertile of the PRAL (OR: 4.16, 95%CI: 1.94, 8.91; p-value < 0.001) and NEAP scores (OR: 3.57, 95%CI: 1.69, 7.53; p-value < 0.001), compared to those in the lowest tertile. After further adjusting for sodium, saturated fatty acid, and fiber intake, the results remained significant for total plant-based protein intake (OR: 0.07, 95%CI: 0.01, 0.38; p-value = 0.002). In conclusion, a higher NEAP or PRAL score may be associated with increased odds of MS, while a higher intake of plant-based protein instead of animal-based protein may be protective.
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Affiliation(s)
- Zahra Saeedirad
- Department of Clinical Nutrition and Dietetics, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran 19816-19573, Iran; (Z.S.); (S.S.); (M.G.); (N.R.); (A.H.)
| | - Shadi Ariyanfar
- Department of Human Nutrition, Foods, and Exercise, College of Agriculture and Life Science, Virginia Tech, Blacksburg, VA 24060, USA;
| | - Morvarid Noormohammadi
- Department of Nutrition, School of Public Health, Iran University of Medical Sciences, Tehran 14496-14535, Iran
| | - Zeinab Ghorbani
- Cardiovascular Diseases Research Center, Department of Cardiology, Heshmat Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht 41937-1311, Iran;
- Department of Clinical Nutrition, School of Medicine, Guilan University of Medical Sciences, Rasht 41937-1311, Iran
| | - Abdorreza Naser Moghadasi
- Multiple Sclerosis Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran 14167-53955, Iran;
| | - Sahar Shahemi
- Department of Clinical Nutrition and Dietetics, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran 19816-19573, Iran; (Z.S.); (S.S.); (M.G.); (N.R.); (A.H.)
- Nutrition and Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran 19839-69411, Iran
| | - Milad Ghanaatgar
- Department of Clinical Nutrition and Dietetics, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran 19816-19573, Iran; (Z.S.); (S.S.); (M.G.); (N.R.); (A.H.)
| | - Nasim Rezaeimanesh
- Department of Clinical Nutrition and Dietetics, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran 19816-19573, Iran; (Z.S.); (S.S.); (M.G.); (N.R.); (A.H.)
- Multiple Sclerosis Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran 14167-53955, Iran;
| | - Azita Hekmatdoost
- Department of Clinical Nutrition and Dietetics, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran 19816-19573, Iran; (Z.S.); (S.S.); (M.G.); (N.R.); (A.H.)
| | - Amir Ghaemi
- Department of Virology, Pasteur Institute of Iran, Tehran 13169-43551, Iran;
| | - Soodeh Razeghi Jahromi
- Department of Clinical Nutrition and Dietetics, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran 19816-19573, Iran; (Z.S.); (S.S.); (M.G.); (N.R.); (A.H.)
- Multiple Sclerosis Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran 14167-53955, Iran;
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Pramanik J, Kumar A, Panchal L, Prajapati B. Countermeasures for Maintaining Cardiovascular Health in Space Missions. Curr Cardiol Rev 2023; 19:57-67. [PMID: 37005513 PMCID: PMC10518885 DOI: 10.2174/1573403x19666230330083225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/21/2023] [Accepted: 02/06/2023] [Indexed: 04/04/2023] Open
Abstract
During space exploration, the human body is subjected to altered atmospheric environments and gravity, exposure to radiation, sleep disturbance, and mental pressures; all these factors are responsible for cardiovascular diseases. Under microgravity, the physiological changes related to cardiovascular diseases are the cephalic fluid shift, dramatic reduction in central venous pressure, changes in blood rheology and endothelial function, cerebrovascular abnormalities, headaches, optic disc edema, intracranial hypertension, congestion of the jugular vein, facial swelling, and loss of taste. Generally, five countermeasures are used to maintain cardiovascular health (during and after space missions), including shielding, nutritional, medicinal, exercise, and artificial gravity. This article concludes with how to reduce space missions' impact on cardiovascular health with the help of various countermeasures.
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Affiliation(s)
- Jhilam Pramanik
- Department of Food Technology, ITM University, Gwalior, Madhya Pradesh, India
| | - Akash Kumar
- Department of Food Technology, SRM University, Sonipat, Haryana, India
| | - Lakshay Panchal
- Maharishi Markandeshwar Institute of Physiotherapy and Rehabilitation, Maharishi Markandeshwar University, Mullana, Haryana, India
| | - Bhupendra Prajapati
- Shree S.K. Patel College of Pharmaceutical Education and Research, Ganpat University, India
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Saul A, Taylor BV, Blizzard L, Simpson-Yap S, Probst YC, Black LJ, Ponsonby AL, Broadley SA, Lechner Scott J, van der Mei I. Long-term dietary acid load is associated with depression in multiple sclerosis, but less evidence was found with fatigue and anxiety. Mult Scler Relat Disord 2023; 69:104415. [PMID: 36434910 DOI: 10.1016/j.msard.2022.104415] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Revised: 10/17/2022] [Accepted: 11/13/2022] [Indexed: 11/16/2022]
Abstract
BACKGROUND Diet-dependent acid-base load has been associated with worsening in mental health, but to date no study has examined this in people with multiple sclerosis (PwMS). We examined the association between potential renal acid load (PRAL) and net endogenous acid production (NEAP) scores and depression, anxiety, and fatigue in PwMS. METHODS Participants with a first clinical diagnosis of CNS demyelination were followed prospectively as part of the AusLong Study (aged 18-59 years at cohort entry). At baseline, 5- and 10-year reviews, PRAL and NEAP scores were calculated using dietary intake in the preceding 12 months calculated from a food frequency questionnaire. At 5- and 10-year reviews, the Hospital Anxiety and Depression Scale was used to assess depression and anxiety, and the Fatigue Severity Scale assessed fatigue. RESULTS Higher PRAL and NEAP scores were associated with increased subsequent absolute value and change in HADS depression scores over five years' follow-up (e.g., highest vs lowest PRAL quartile, 5-year change in HADS-D score: β=+3.01, 95%CI= 1.54, 4.48, p<0.001). The level of depression at the 10-year review was determined by both the baseline dietary acid scores and baseline-5-year changes in dietary acid scores (e.g., PRAL change from baseline to 5-year review, 10-year review HADS-D score: β=+0.09, 95%CI= 0.03, 0.15, p<0.001, NEAP change from baseline to 5-year review, 10-year review HADS-D score: β=+0.07, 95%CI= 0.01, 0.14, p=0.03). Some associations were observed with anxiety and fatigue but were much weaker and less consistent. CONCLUSION Our findings indicate that a higher dietary acid load potentially has a long-term influence on the level of depression in PwMS. The evidence is less convincing for anxiety and fatigue.
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Affiliation(s)
- A Saul
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia
| | - B V Taylor
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia
| | - L Blizzard
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia
| | - S Simpson-Yap
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia; Melbourne School of Population & Global Health, The University of Melbourne, Melbourne, Australia
| | - Y C Probst
- Illawarra Health and Medical Research Institute, Wollongong, Australia; School of Medicine, University of Wollongong, Wollongong, Australia
| | - L J Black
- Curtin School of Population Health, Curtin University, Perth, Australia
| | - A L Ponsonby
- Murdoch Children's Research Institute, Royal Children's Hospital, University of Melbourne, VIC, Australia; The Florey Institute of Neuroscience & Mental Health, Parkville, VIC, Australia
| | - S A Broadley
- School of Medicine, Griffith University, Gold Coast, Australia
| | - J Lechner Scott
- Department of Neurology, John Hunter Hospital, Newcastle, New South Wales, Australia; Faculty of Medicine and Public Health, Hunter Medical Research Institute, University of Newcastle, New South Wales, Australia
| | - I van der Mei
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia.
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Bone metabolism during strict head-down tilt bed rest and exposure to elevated levels of ambient CO 2. NPJ Microgravity 2022; 8:57. [PMID: 36526672 PMCID: PMC9758179 DOI: 10.1038/s41526-022-00245-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 11/03/2022] [Indexed: 12/23/2022] Open
Abstract
Astronauts on the International Space Station are exposed to levels of atmospheric carbon dioxide (CO2) above typical terrestrial levels. We explored the possibility that increased levels of ambient CO2 further stimulate bone resorption during bed rest. We report here data from 2 ground-based spaceflight analog studies in which 12 male and 7 female subjects were placed in a strict 6° head-down tilt (HDT) position for either 30 days at 0.5% ambient CO2 or 60 days with nominal environmental exposure to CO2. Bone mineral density (BMD) and bone mineral content (BMC) were determined using dual-energy X-ray absorptiometry (DXA). Blood and urine were collected before and after HDT for biochemical analysis. No change was detected in either BMD or BMC, as expected given the study duration. Bone resorption markers increased after bed rest as expected; however, elevated CO2 had no additive effect. Elevated CO2 did not affect concentrations of minerals in serum and urine. Serum parathyroid hormone and 1,25-dihydroxyvitamin D were both reduced after bed rest, likely secondary to calcium efflux from bone. In summary, exposure to 0.5% CO2 for 30 days did not exacerbate the typical bone resorption response observed after HDT bed rest. Furthermore, results from these strict HDT studies were similar to data from previous bed rest studies, confirming that strict 30-60 days of HDT can be used to evaluate changes in bone metabolism. This is valuable in the continuing effort to develop and refine efficacious countermeasure protocols to mitigate bone loss during spaceflight in low-Earth orbit and beyond.
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Zhao R, Zhou L, Lei G, Wang S, Li Y, Yang X, Xiong G, Hao L. Dietary Acid Load Is Positively Associated With Risk of Gestational Diabetes Mellitus in a Prospective Cohort of Chinese Pregnant Women. Front Nutr 2022; 9:892698. [PMID: 35694169 PMCID: PMC9184257 DOI: 10.3389/fnut.2022.892698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 05/09/2022] [Indexed: 11/16/2022] Open
Abstract
Background Growing evidence suggests that dietary acid load plays an important role in the development of type 2 diabetes. However, prospective studies on the relationship between dietary acid load and gestational diabetes mellitus (GDM) are limited in the pregnant population. This study aimed to investigate the effect of dietary acid load during early pregnancy on the risk of GDM in Chinese pregnant women. Methods A total of 1,327 pregnant women were enrolled from an ongoing prospective study of the Tongji Birth cohort (TJBC) in Wuhan, China. Dietary intake was assessed before 20 weeks using a 74-item semiquantitative food frequency questionnaire (FFQ). The dietary acid load was estimated using potential renal acid load (PRAL), net endogenous acid production (NEAP), and animal protein to potassium ratio (A:P ratio). A 75g 2-h oral glucose tolerance test (OGTT) was performed at 24-28 gestational weeks to diagnose GDM. Results The mean (standard deviation) values for PRAL score, NEAP score, and A:P ratio were 0.8 ± 11.3 mEq/day, 45.3 ± 16.5 mEq/day, and 9.8 ± 6.0, respectively. There was a significant positive correlation of dietary acid load with the intake of red meat, poultry, fish, and eggs, and a negative correlation with the intake of vegetables, fruits, nuts, and legumes (all P < 0.05). Compared to the lowest tertile, the highest tertile of dietary acid load, including PRAL score (odds ratio [OR]: 2.26, 95% confidence interval [CI] = 1.38–3.71, P-trend = 0.002), NEAP score (OR: 2.02, 95% CI = 1.25–3.27, P-trend = 0.009), and A:P ratio (2.08, 95% CI = 1.30–3.31, P-trend = 0.005), significantly increased the risk of GDM. In addition, the dietary acid load was also significantly associated with an increase in 1-h and 2-h post-load blood glucose concentrations (all P-trend < 0.05). Conclusion We found a significant positive association between dietary acid load during early pregnancy and the risk of GDM in a Chinese population, suggesting that the reduction of food sources of dietary acid load may be an effective strategy for preventing the risk of GDM.
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Affiliation(s)
- Rui Zhao
- Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety and the Ministry of Education (MOE) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Leilei Zhou
- Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety and the Ministry of Education (MOE) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Gang Lei
- The Central Hospital of Wuhan, Wuhan, China
| | - Shanshan Wang
- Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety and the Ministry of Education (MOE) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yan Li
- Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety and the Ministry of Education (MOE) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xuefeng Yang
- Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety and the Ministry of Education (MOE) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Guoping Xiong
- The Central Hospital of Wuhan, Wuhan, China
- *Correspondence: Guoping Xiong,
| | - Liping Hao
- Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety and the Ministry of Education (MOE) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Liping Hao,
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Tang H, Rising HH, Majji M, Brown RD. Long-Term Space Nutrition: A Scoping Review. Nutrients 2021; 14:nu14010194. [PMID: 35011072 PMCID: PMC8747021 DOI: 10.3390/nu14010194] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 12/23/2021] [Accepted: 12/28/2021] [Indexed: 01/30/2023] Open
Abstract
This scoping review aimed to identify current evidence and gaps in the field of long-term space nutrition. Specifically, the review targeted critical nutritional needs during long-term manned missions in outer space in addition to the essential components of a sustainable space nutrition system for meeting these needs. The search phrase "space food and the survival of astronauts in long-term missions" was used to collect the initial 5432 articles from seven Chinese and seven English databases. From these articles, two independent reviewers screened titles and abstracts to identify 218 articles for full-text reviews based on three themes and 18 keyword combinations as eligibility criteria. The results suggest that it is possible to address short-term adverse environmental factors and nutritional deficiencies by adopting effective dietary measures, selecting the right types of foods and supplements, and engaging in specific sustainable food production and eating practices. However, to support self-sufficiency during long-term space exploration, the most optimal and sustainable space nutrition systems are likely to be supported primarily by fresh food production, natural unprocessed foods as diets, nutrient recycling of food scraps and cultivation systems, and the establishment of closed-loop biospheres or landscape-based space habitats as long-term life support systems.
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Affiliation(s)
- Hong Tang
- College of Landscape and Tourism, Gansu Agricultural University, Lanzhou 730070, China;
| | - Hope Hui Rising
- Department of Landscape Architecture and Urban Planning, Texas A&M University, College Station, TX 77843, USA;
- Correspondence:
| | - Manoranjan Majji
- Department of Aerospace Engineering, Texas A&M University, College Station, TX 77843, USA;
| | - Robert D. Brown
- Department of Landscape Architecture and Urban Planning, Texas A&M University, College Station, TX 77843, USA;
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Mousavi M, Jahromi SR, Togha M, Ghorbani Z, Hekmatdoost A, Rafiee P, Torkan B, Shirani P, Ansari H, Karami A, Nourmohammadi M, Khorsha F. The Association Between Dietary Acid Load and Odds of Migraine: A Case-Control Survey. Neurol Ther 2021; 10:335-348. [PMID: 33893990 PMCID: PMC8140036 DOI: 10.1007/s40120-021-00247-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 03/24/2021] [Indexed: 01/03/2023] Open
Abstract
INTRODUCTION It has been shown that a high acid load in the human body can affect inflammatory factors and the nitric oxide pathway. These factors are also thought to play an important role in the initiation of migraine attacks. We have therefore explored the association between dietary acid load and odds of migraine in a case-control study. METHODS The migraine group (n = 514, diagnosed according to the International Classification of Headache Disorders 3rd edition [ICHDIII] criteria) was recruited from a tertiary headache clinic. The controls consisted of 582 sex-matched healthy volunteers who were randomly selected from the general population. A validated 168-item semiquantitative food frequency questionnaire was used for dietary intake assessments. Estimation of the dietary acid load was performed using three different measures: potential renal acid load (PRAL) score, net endogenous acid production (NEAP) score, and protein/potassium ratio. RESULTS Multivariable logistic regression analysis showed that, in comparison with the lowest tertile, the highest tertile of dietary acid load measures, including PRAL (odds ratio [OR] 7.208, 95% confidence intervals [CI] 3.33-15.55), and NEAP (OR 4.108, 95% CI 1.924-8.774) scores and the protein/potassium ratio (OR 4.127, 95% CI 1.933-8.814), significantly increased the odds of migraine (P value for trend ≤ 0.001). CONCLUSION In this study, high dietary acid load was associated with higher odds of migraine. It is therefore possible that restricting dietary acid load could reduce the odds of migraine in susceptible subjects. However, due to the preliminary nature of the current evidence, caution is advised in drawing a definitive conclusion. More well-designed studies are required for a better understanding of this important issue.
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Affiliation(s)
- Maryam Mousavi
- Department of Clinical Nutrition and Dietetics, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Headache Department, Iranian Centre of Neurological Research, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Soodeh Razeghi Jahromi
- Department of Clinical Nutrition and Dietetics, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Headache Department, Iranian Centre of Neurological Research, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Mansoureh Togha
- Headache Department, Iranian Centre of Neurological Research, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran.
| | - Zeinab Ghorbani
- Department of Cardiology, Cardiovascular Diseases Research Centre, School of Medicine, Heshmat Hospital-Guilan University of Medical Sciences, Rasht, Iran
| | - Azita Hekmatdoost
- Department of Clinical Nutrition and Dietetics, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Pegah Rafiee
- Department of Clinical Nutrition and Dietetics, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Headache Department, Iranian Centre of Neurological Research, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Boshra Torkan
- Department of Clinical Nutrition and Dietetics, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Headache Department, Iranian Centre of Neurological Research, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Pedram Shirani
- Department of Clinical Nutrition and Dietetics, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Headache Department, Iranian Centre of Neurological Research, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Hossein Ansari
- Department of Neurology, University of California San Diego (UCSD), San Diego, USA
| | - Ahmadreza Karami
- Department of Clinical Nutrition and Dietetics, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Headache Department, Iranian Centre of Neurological Research, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Morvarid Nourmohammadi
- Department of Clinical Nutrition and Dietetics, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Headache Department, Iranian Centre of Neurological Research, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Faezeh Khorsha
- Headache Department, Iranian Centre of Neurological Research, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran.,Department of Cardiology, Cardiovascular Diseases Research Centre, School of Medicine, Heshmat Hospital-Guilan University of Medical Sciences, Rasht, Iran
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Nozawa Y, Wagatsuma Y. Protein Intake and Physical Performance Following Long-Term Stay on the International Space Station. Aerosp Med Hum Perform 2021; 92:153-159. [PMID: 33754972 DOI: 10.3357/amhp.5640.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
INTRODUCTION: Exposure to microgravity reduces muscle mass, volume, and performance. The ingestion of protein, especially combined with carbohydrate intake and exercise after ingestion, improves net muscle protein synthesis and increases muscle mass. However, there are few studies on this relationship during and after a long-term spaceflight. The objective of this study was to investigate the influence of protein and the combined effects of carbohydrate intake on muscle performance following long-term spaceflight.METHODS: This study is a retrospective cohort study involving secondary analysis of data stored in the NASA Lifetime Surveillance of Astronaut Health Repository. Multivariable analysis was performed to evaluate the impact of protein intake on physical performance by considering covariates potentially associated with each model.RESULTS: After adjusting for sex, age, flight week, energy intake, and preflight physical performance, protein intake was found to be significantly associated with concentric measurements for knee extension ( 51.66), ankle plantar flexion ( 32.86), and eccentric measurements for ankle plantar flexion ( 79.85) at 5 d after landing. Significant associations remained after controlling for exercise effect. No significant interaction between protein and carbohydrate intake was observed in either model.DISCUSSION: Protein intake during spaceflight was related to physical performance for knee extension and ankle plantar flexion, even after taking exercise effect into consideration. However, protein and carbohydrate intake provided no synergetic benefit. This suggests that high protein intake, about twice the current average intake, may serve as a countermeasure to offset the negative effects of long-duration spaceflights.Nozawa Y, Wagatsuma Y. Protein intake and physical performance following long-term stay on the International Space Station. Aerosp Med Hum Perform. 2021; 92(3):153159.
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Diet-dependent acid load and the risk of colorectal cancer and adenoma: a case-control study. Public Health Nutr 2020; 24:4474-4481. [PMID: 33087202 DOI: 10.1017/s1368980020003420] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
OBJECTIVES Colorectal cancer (CRC) is the third and second most prevalent cancer in men and women, respectively. Various epidemiological studies indicated that dietary factors are implicated in the aetiology of CRC and its precursor, colorectal adenomas (CRA). Recently, much attention has been given to the role of acid-base balance in the development of chronic diseases including cancers. Therefore, the aim of the current study is to examine the association of diet-dependent acid load and the risk of CRC and CRA. DESIGN In this case-control study, potential renal acid load (PRAL) was computed based on dietary intake of participants assessed via a validated FFQ. Negative PRAL values indicated a base-forming potential, while positive values of PRAL implied acid-forming potential of diet. Logistic regression was used to derive OR and 95 % CI after adjusting for confounders. SETTING Tehran, Iran. PARTICIPANTS A total of 499 participants aged 30-70 years were included in the study (240 hospital controls, 129 newly diagnosed CRC and 130 newly diagnosed CRA). The current study was conducted between December 2016 and September 2018. RESULTS After adjusting for potential confounders, a higher PRAL was associated with increased odds of CRC and CRA. The highest v. the lowest tertile of PRAL for CRC and CRA was OR 4·82 (95 % CI 2·51-9·25) and OR 2·47 (95 % CI 1·38-4·42), respectively. CONCLUSIONS The findings of the current study suggested that higher diet-dependent acid load is associated with higher risk of CRC and CRA.
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Selected discoveries from human research in space that are relevant to human health on Earth. NPJ Microgravity 2020; 6:5. [PMID: 32128361 PMCID: PMC7016134 DOI: 10.1038/s41526-020-0095-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 12/06/2019] [Indexed: 12/14/2022] Open
Abstract
A substantial amount of life-sciences research has been performed in space since the beginning of human spaceflight. Investigations into bone loss, for example, are well known; other areas, such as neurovestibular function, were expected to be problematic even before humans ventured into space. Much of this research has been applied research, with a primary goal of maintaining the health and performance of astronauts in space, as opposed to research to obtain fundamental understanding or to translate to medical care on Earth. Some people—scientists and concerned citizens—have questioned the broader scientific value of this research, with the claim that the only reason to perform human research in space is to keep humans healthy in space. Here, we present examples that demonstrate that, although this research was focused on applied goals for spaceflight participants, the results of these studies are of fundamental scientific and biomedical importance. We will focus on results from bone physiology, cardiovascular and pulmonary systems, and neurovestibular studies. In these cases, findings from spaceflight research have provided a foundation for enhancing healthcare terrestrially and have increased our knowledge of basic physiological processes.
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Alferink LJM, Kiefte-de Jong JC, Erler NS, de Knegt RJ, Hoorn EJ, Ikram MA, Janssen HLA, Metselaar HJ, Franco OH, Darwish Murad S. Diet-Dependent Acid Load-The Missing Link Between an Animal Protein-Rich Diet and Nonalcoholic Fatty Liver Disease? J Clin Endocrinol Metab 2019; 104:6325-6337. [PMID: 30977830 DOI: 10.1210/jc.2018-02792] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Accepted: 04/08/2019] [Indexed: 12/22/2022]
Abstract
OBJECTIVE Our group recently showed that animal protein was independently associated with nonalcoholic fatty liver disease (NAFLD). We hypothesize that this may be explained by a high diet-dependent acid load [dietary acid load (DAL)]. METHODS This cross-sectional study is embedded in a prospective population-based cohort. We estimated DAL proxies via food-frequency questionnaires using potential renal acid load (PRAL; using dietary protein, phosphorus, potassium, calcium, and magnesium intake), net endogenous acid production (NEAP; using protein and potassium intake), and the animal protein-to-potassium ratio (A:P). We defined NAFLD using ultrasound after excluding secondary steatogenic causes. We used logistic regression models-adjusted for sociodemographic, lifestyle, and metabolic traits-on categorized [quartile (Q)1 to 4] and continuous DAL proxies (allowing for nonlinearity) and NAFLD. RESULTS We included 3882 participants, of which 1337 had NAFLD. All DAL proxies were higher, meaning more acidic, in individuals with NAFLD (PRAL, -2.9 vs -5.5 mEq/d; NEAP, 37.0 vs 35.1 mEq/d; and A:P, 13.3 vs 12.4; all P < 0.001). The highest Q of DAL proxies was associated with NAFLD independent of sociodemographic and lifestyle confounders, but significance dissipated after correction for metabolic confounders and multiple testing. However, the P value for nonlinearity was significant in all DAL proxies (P < 0.001). Natural cubic splines performed better with than without DAL proxies in the fully adjusted model (all P ≤ 0.038). The highest probability of NAFLD was found for an acidic diet. CONCLUSIONS This study showed an independent nonlinear association between an acidic diet and NAFLD. Further studies with acid-base biomarkers are needed, but our findings might provide a mechanistic explanation for the harmful association between an animal protein-rich diet and NAFLD.
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Affiliation(s)
- Louise J M Alferink
- Department of Gastroenterology and Hepatology, Erasmus MC, University Medical Center, CA Rotterdam, Netherlands
| | - Jessica C Kiefte-de Jong
- Department of Epidemiology, Erasmus MC, University Medical Center, CA Rotterdam, Netherlands
- Department of Public Health and Primary Care, Leiden University Medical Center, LUMC-Campus, VA The Hague, Netherlands
| | - Nicole S Erler
- Department of Biostatistics, Erasmus MC, University Medical Center, CA Rotterdam, Netherlands
| | - Robert J de Knegt
- Department of Gastroenterology and Hepatology, Erasmus MC, University Medical Center, CA Rotterdam, Netherlands
| | - Ewout J Hoorn
- Division of Nephrology and Transplantation, Department of Internal Medicine, Erasmus MC, CN Rotterdam, Netherlands
| | - M Arfan Ikram
- Department of Epidemiology, Erasmus MC, University Medical Center, CA Rotterdam, Netherlands
| | - Harry L A Janssen
- Department of Gastroenterology and Hepatology, Erasmus MC, University Medical Center, CA Rotterdam, Netherlands
- Toronto Centre of Liver Disease, Toronto General Hospital, University Health Network, Toronto, Ontario, Canada
| | - Herold J Metselaar
- Department of Gastroenterology and Hepatology, Erasmus MC, University Medical Center, CA Rotterdam, Netherlands
| | - Oscar H Franco
- Department of Epidemiology, Erasmus MC, University Medical Center, CA Rotterdam, Netherlands
- Institute of Social and Preventive Medicine, University of Bern, Bern, Switzerland
| | - Sarwa Darwish Murad
- Department of Gastroenterology and Hepatology, Erasmus MC, University Medical Center, CA Rotterdam, Netherlands
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12
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Park YMM, Steck SE, Fung TT, Merchant AT, Elizabeth Hodgson M, Keller JA, Sandler DP. Higher diet-dependent acid load is associated with risk of breast cancer: Findings from the sister study. Int J Cancer 2018; 144:1834-1843. [PMID: 30247761 DOI: 10.1002/ijc.31889] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 08/16/2018] [Accepted: 09/10/2018] [Indexed: 01/22/2023]
Abstract
Dietary factors that contribute to chronic low-grade metabolic acidosis have been linked to breast cancer risk, but to date no epidemiologic study has examined diet-dependent acid load and breast cancer. We used data from 43,570 Sister Study participants who completed a validated food frequency questionnaire at enrollment (2003-2009) and satisfied eligibility criteria. The Potential Renal Acid Load (PRAL) score was used to estimate diet-dependent acid load. Higher scores reflect greater consumption of protein and phosphorus, and lower consumption of potassium, calcium and magnesium. The association between PRAL and breast cancer was evaluated using multivariable Cox proportional hazards regression. We identified 1,614 invasive breast cancers diagnosed at least 1 year after enrollment (mean follow-up, 7.6 years). The highest PRAL quartile, reflecting greater acid-forming potential, was associated with increased risk of breast cancer (HRhighest vs. lowest quartile : 1.21 [95% CI, 1.04-1.41], ptrend = 0.04). The association was more pronounced for estrogen receptor (ER)-negative (HRhighest vs. lowest quartile : 1.67 [95% CI, 1.07-2.61], ptrend = 0.03) and triple-negative breast cancer (HRhighest vs. lowest quartile : 2.20 [95% CI, 1.23-3.95], ptrend = 0.02). Negative PRAL scores, representing consumption of alkaline diets, were associated with decreased risk of ER-negative and triple-negative breast cancer, compared to a PRAL score of 0 representing neutral pH. Higher diet-dependent acid load may be a risk factor for breast cancer while alkaline diets may be protective. Since PRAL scores are positively correlated with meat consumption and negatively correlated with fruit and vegetable intake, results also suggest that diets high in fruits and vegetables and low in meat may be protective against hormone receptor negative breast cancer.
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Affiliation(s)
- Yong-Moon Mark Park
- Epidemiology Branch, National Institute of Environmental Health Sciences, Research Triangle Park, NC
| | - Susan E Steck
- Cancer Prevention and Control Program, University of South Carolina, Columbia, SC.,Department of Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, Columbia, SC
| | - Teresa T Fung
- Department of Nutrition, Simmons College, Boston, MA.,Department of Nutrition, Harvard TH Chan School of Public Health, Boston, MA
| | - Anwar T Merchant
- Department of Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, Columbia, SC
| | | | | | - Dale P Sandler
- Epidemiology Branch, National Institute of Environmental Health Sciences, Research Triangle Park, NC
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Zwart SR, Rice BL, Dlouhy H, Shackelford LC, Heer M, Koslovsky MD, Smith SM. Dietary acid load and bone turnover during long-duration spaceflight and bed rest. Am J Clin Nutr 2018; 107:834-844. [PMID: 29722847 PMCID: PMC6862931 DOI: 10.1093/ajcn/nqy029] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 02/01/2018] [Indexed: 01/10/2023] Open
Abstract
Background Bed rest studies document that a lower dietary acid load is associated with lower bone resorption. Objective We tested the effect of dietary acid load on bone metabolism during spaceflight. Design Controlled 4-d diets with a high or low animal protein-to-potassium (APro:K) ratio (High and Low diets, respectively) were given to 17 astronauts before and during spaceflight. Each astronaut had 1 High and 1 Low diet session before flight and 2 High and 2 Low sessions during flight, in addition to a 4-d session around flight day 30 (FD30), when crew members were to consume their typical in-flight intake. At the end of each session, blood and urine samples were collected. Calcium, total protein, energy, and sodium were maintained in each crew member's preflight and in-flight controlled diets. Results Relative to preflight values, N-telopeptide (NTX) and urinary calcium were higher during flight, and bone-specific alkaline phosphatase (BSAP) was higher toward the end of flight. The High and Low diets did not affect NTX, BSAP, or urinary calcium. Dietary sulfur and age were significantly associated with changes in NTX. Dietary sodium and flight day were significantly associated with urinary calcium during flight. The net endogenous acid production (NEAP) estimated from the typical dietary intake at FD30 was associated with loss of bone mineral content in the lumbar spine after the mission. The results were compared with data from a 70-d bed rest study, in which control (but not exercising) subjects' APro:K was associated with higher NTX during bed rest. Conclusions Long-term lowering of NEAP by increasing vegetable and fruit intake may protect against changes in loss of bone mineral content during spaceflight when adequate calcium is consumed, particularly if resistive exercise is not being performed. This trial was registered at clinicaltrials.gov as NCT01713634.
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Affiliation(s)
- Sara R Zwart
- Universities Space Research Association, Houston, TX
- Department of Preventive Medicine and Community Health, University of Texas Medical Branch, Galveston, TX
| | - Barbara L Rice
- Enterprise Advisory Services, Inc., Houston, TX
- KBRwyle, Houston, TX
| | - Holly Dlouhy
- Enterprise Advisory Services, Inc., Houston, TX
- KBRwyle, Houston, TX
| | - Linda C Shackelford
- Human Health and Performance Directorate, NASA Lyndon B. Johnson Space Center, Houston, TX
| | - Martina Heer
- Institute of Nutritional and Food Sciences, University of Bonn, Bonn, Germany
| | | | - Scott M Smith
- Human Health and Performance Directorate, NASA Lyndon B. Johnson Space Center, Houston, TX
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14
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Jayedi A, Shab-Bidar S. Dietary acid load and risk of type 2 diabetes: A systematic review and dose-response meta-analysis of prospective observational studies. Clin Nutr ESPEN 2017; 23:10-18. [PMID: 29460782 DOI: 10.1016/j.clnesp.2017.12.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 12/03/2017] [Accepted: 12/06/2017] [Indexed: 11/27/2022]
Abstract
BACKGROUND & AIMS Existing evidence suggests a link between acid-forming potential of diet and type 2 diabetes. But the degree of the associations and shape of the dose-response relations across different indices of diet-dependent acid load and risk of type 2 diabetes and potential confounding by sex have not been established. We aimed to test the dose-response association of different measures of dietary acid load and risk of incident type 2 diabetes, with considering the sex as a potential confounder. METHODS Systematic search was done using PubMed and Scopus, from inception up to September 2017. Prospective observational studies reporting the risk estimates of type 2 diabetes for three or more quantitative categories of potential renal acid load (PRAL), net endogenous acid production (NEAP) and animal protein-to-potassium ratio (A:P) scores were included. Pooled relative risks (RRs) were calculated using random effects models. RESULTS Seven prospective cohort studies with 319,542 participants and 17,986 incident cases of type 2 diabetes were included. Pooled RRs for a 5 unit increment in dietary PRAL, NEAP and A:P was 1.04 (95% CI: 1.01, 1.06; I2 = 79%, n = 7), 1.03 (95% CI: 1.01, 1.04; I2 = 54%, n = 7), and 1.11 (95% CI: 1.07, 1.15; I2 = 41%, n = 3), respectively. Subgroup analysis resulted in significant positive relationship only among women, compared with men. There was a linear association between NEAP and A:P scores and risk of type 2 diabetes, whereas the association appeared to be U-shaped in analysis of PRAL. CONCLUSIONS Adherence to a diet with high acid-forming potential might increase the risk of type 2 diabetes. Shape of the dose-response relations across different indices of dietary acid load and potential sex differences in the associations need to be further explored. The interpretation of the results is limited by low number of studies.
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Affiliation(s)
- Ahmad Jayedi
- Department of Community Nutrition, School of Nutritional Science and Dietetics, Tehran University of Medical Sciences, Tehran, Iran
| | - Sakineh Shab-Bidar
- Department of Community Nutrition, School of Nutritional Science and Dietetics, Tehran University of Medical Sciences, Tehran, Iran.
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de Jonge EAL, Koromani F, Hofman A, Uitterlinden AG, Franco OH, Rivadeneira F, Kiefte-de Jong JC. Dietary acid load, trabecular bone integrity, and mineral density in an ageing population: the Rotterdam study. Osteoporos Int 2017; 28:2357-2365. [PMID: 28405729 PMCID: PMC5524850 DOI: 10.1007/s00198-017-4037-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 03/31/2017] [Indexed: 11/25/2022]
Abstract
UNLABELLED We studied the relation between a diet that is high in acid-forming nutrients (e.g. proteins) and low in base-forming nutrients (e.g. potassium) and bone structure. We showed a negative relation, which was more prominent if proteins were of animal rather than of vegetable origin and if intake of dietary fibre was high. INTRODUCTION Studies on dietary acid load (DAL) and fractures have shown inconsistent results. Associations between DAL, bone mineral density (BMD) and trabecular bone integrity might play a role in these inconsistencies and might be influenced by renal function and dietary fibre intake. Therefore, our aim was to study (1) associations of DAL with BMD and with the trabecular bone score (TBS) and (2) the potential influence of renal function and dietary fibre in these associations. METHODS Dutch individuals aged 45 years and over (n = 4672) participating in the prospective cohort of the Rotterdam study were included. Based on food frequency questionnaires, three indices of DAL were calculated: the net endogenous acid production (NEAP) and the ratios of vegetable or animal protein and potassium (VegPro/K and AnPro/K). Data on lumbar spinal TBS and BMD were derived from dual-energy X-ray absorptiometry measurements. RESULTS Independent of confounders, NEAP and AnPro/K, but not VegPro/K, were associated with low TBS (standardized β (95%) = -0.04 (-0.07, -0.01) and -0.08 (-0.11, -0.04)) but not with BMD. Associations of AnPro/K and VegPro/K with TBS were non-linear and differently shaped. Unfavourable associations between NEAP, BMD and TBS were mainly present in subgroups with high fibre intake. CONCLUSIONS High NEAP was associated with low TBS. Associations of AnPro/K and VegPro/K and TBS were non-linear and differently shaped. No significant associations of DAL with BMD were observed, nor was there any significant interaction between DAL and renal function. Mainly in participants with high intake of dietary fibre, DAL might be detrimental to bone.
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Affiliation(s)
- E A L de Jonge
- Department of Epidemiology, Erasmus Medical University Centre, Rotterdam, The Netherlands
- Department of Internal Medicine, Erasmus Medical University Centre, Rotterdam, The Netherlands
| | - F Koromani
- Department of Epidemiology, Erasmus Medical University Centre, Rotterdam, The Netherlands
- Department of Internal Medicine, Erasmus Medical University Centre, Rotterdam, The Netherlands
| | - A Hofman
- Department of Epidemiology, Erasmus Medical University Centre, Rotterdam, The Netherlands
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - A G Uitterlinden
- Department of Epidemiology, Erasmus Medical University Centre, Rotterdam, The Netherlands
- Department of Internal Medicine, Erasmus Medical University Centre, Rotterdam, The Netherlands
| | - O H Franco
- Department of Epidemiology, Erasmus Medical University Centre, Rotterdam, The Netherlands
| | - F Rivadeneira
- Department of Internal Medicine, Erasmus Medical University Centre, Rotterdam, The Netherlands
| | - J C Kiefte-de Jong
- Department of Epidemiology, Erasmus Medical University Centre, Rotterdam, The Netherlands.
- Department of Global Public Health, Leiden University College, The Hague, The Netherlands.
- Department of Paediatrics, Erasmus MC, Rotterdam, The Netherlands.
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16
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Bone-Protective Effects of Dried Plum in Postmenopausal Women: Efficacy and Possible Mechanisms. Nutrients 2017; 9:nu9050496. [PMID: 28505102 PMCID: PMC5452226 DOI: 10.3390/nu9050496] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2017] [Revised: 05/11/2017] [Accepted: 05/12/2017] [Indexed: 12/12/2022] Open
Abstract
Osteoporosis is an age-related chronic disease characterized by a loss of bone mass and quality, and is associated with an increased risk of fragility fractures. Postmenopausal women are at the greatest risk of developing osteoporosis due to the cessation in ovarian hormone production, which causes accelerated bone loss. As the demographic shifts to a more aged population, a growing number of postmenopausal women will be afflicted with osteoporosis. Certain lifestyle factors, including nutrition and exercise, are known to reduce the risk of developing osteoporosis and therefore play an important role in bone health. In terms of nutrition, accumulating evidence suggests that dried plum (Prunus domestica L.) is potentially an efficacious intervention for preventing and reversing bone mass and structural loss in an ovariectomized rat model of osteoporosis, as well as in osteopenic postmenopausal women. Here, we provide evidence supporting the efficacy of dried plum in preventing and reversing bone loss associated with ovarian hormone deficiency in rodent models and in humans. We end with the results of a recent follow-up study demonstrating that postmenopausal women who previously consumed 100 g dried plum per day during our one-year clinical trial conducted five years earlier retained bone mineral density to a greater extent than those receiving a comparative control. Additionally, we highlight the possible mechanisms of action by which bioactive compounds in dried plum exert bone-protective effects. Overall, the findings of our studies and others strongly suggest that dried plum in its whole form is a promising and efficacious functional food therapy for preventing bone loss in postmenopausal women, with the potential for long-lasting bone-protective effects.
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17
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Heer M, Baecker N, Frings-Meuthen P, Graf S, Zwart SR, Biolo G, Smith SM. Effects of high-protein intake on bone turnover in long-term bed rest in women. Appl Physiol Nutr Metab 2017; 42:537-546. [DOI: 10.1139/apnm-2016-0292] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Bed rest (BR) causes bone loss, even in otherwise healthy subjects. Several studies suggest that ambulatory subjects may benefit from high-protein intake to stimulate protein synthesis and to maintain muscle mass. However, increasing protein intake above the recommended daily intake without adequate calcium and potassium intake may increase bone resorption. We hypothesized that a regimen of high-protein intake (HiPROT), applied in an isocaloric manner during BR, with calcium and potassium intake meeting recommended values, would prevent any effect of BR on bone turnover. After a 20-day ambulatory adaptation to a controlled environment, 16 women participated in a 60-day, 6° head-down-tilt (HDT) BR and were assigned randomly to 1 of 2 groups. Control (CON) subjects (n = 8) received 1 g/(kg body mass·day)−1 dietary protein. HiPROT subjects (n = 8) received 1.45 g protein/(kg body mass·day)−1 plus an additional 0.72 g branched-chain amino acids per day during BR. All subjects received an individually tailored diet (before HDTBR: 1888 ± 98 kcal/day; during HDTBR: 1604 ± 125 kcal/day; after HDTBR: 1900 ± 262 kcal/day), with the CON group’s diet being higher in fat and carbohydrate intake. High-protein intake exacerbated the BR-induced increase in bone resorption marker C-telopeptide (>30%) (p < 0.001) by the end of BR. Bone formation markers were unaffected by BR and high-protein intake. We conclude that high-protein intake in BR might increase bone loss. Further long-duration studies are mandatory to show how the positive effect of protein on muscle mass can be maintained without the risk of reducing bone mineral density.
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Affiliation(s)
- Martina Heer
- Department of Nutrition and Food Sciences, Nutritional Physiology, University of Bonn, 53115 Bonn, Germany
| | - Natalie Baecker
- Department of Nutrition and Food Sciences, Nutritional Physiology, University of Bonn, 53115 Bonn, Germany
| | - Petra Frings-Meuthen
- German Aerospace Center (DLR), Institute of Aerospace Medicine, 51147 Cologne, Germany
| | - Sonja Graf
- Department of Nutrition and Food Sciences, Nutritional Physiology, University of Bonn, 53115 Bonn, Germany
| | - Sara R. Zwart
- University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Gianni Biolo
- Department of Clinical, Technological and Morphological Sciences, Division of Internal Medicine, University of Trieste, 34127 Trieste, Italy
| | - Scott M. Smith
- Human Health and Performance Directorate, NASA Lyndon B. Johnson Space Center, Houston, TX 77058, USA
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18
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Kiefte-de Jong JC, Li Y, Chen M, Curhan GC, Mattei J, Malik VS, Forman JP, Franco OH, Hu FB. Diet-dependent acid load and type 2 diabetes: pooled results from three prospective cohort studies. Diabetologia 2017; 60:270-279. [PMID: 27858141 PMCID: PMC5831375 DOI: 10.1007/s00125-016-4153-7] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2016] [Accepted: 10/17/2016] [Indexed: 02/08/2023]
Abstract
AIMS/HYPOTHESIS Studies suggest a potential link between low-grade metabolic acidosis and type 2 diabetes. A western dietary pattern increases daily acid load but the association between diet-dependent acid load and type 2 diabetes is still unclear. This study aimed to assess whether diet-dependent acid load is associated with the risk of type 2 diabetes. METHODS We examined the association between energy-adjusted net endogenous acid production (NEAP), potential renal acid load (PRAL) and animal protein-to-potassium ratio (A:P) on incident type 2 diabetes in 67,433 women from the Nurses' Health Study, 84,310 women from the Nurses' Health Study II and 35,743 men from the Health Professionals' Follow-up Study who were free from type 2 diabetes, cardiovascular disease and cancer at baseline. Study-specific HRs were estimated using Cox proportional hazards models with time-varying covariates and were pooled using a random effects meta-analysis. RESULTS We documented 15,305 cases of type 2 diabetes during 4,025,131 person-years of follow-up. After adjustment for diabetes risk factors, dietary NEAP, PRAL and A:P were positively associated with type 2 diabetes (pooled HR [95% CI] for highest (Q5) vs lowest quintile (Q1): 1.29 [1.22, 1.37], p trend <0.0001; 1.29 [1.22, 1.36], p trend <0.0001 and 1.32 [1.24, 1.40], p trend <0.0001 for NEAP, PRAL and A:P, respectively). These results were not fully explained by other dietary factors including glycaemic load and dietary quality (HR [95% CI] for Q5 vs Q1: 1.21 [1.09, 1.33], p trend <0.0001; 1.19 [1.08, 1.30] and 1.26 [1.17, 1.36], p trend <0.0001 for NEAP, PRAL and A:P, respectively). CONCLUSIONS/INTERPRETATION This study suggests that higher diet-dependent acid load is associated with an increased risk of type 2 diabetes. This association is not fully explained by diabetes risk factors and overall diet quality.
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Affiliation(s)
- Jessica C Kiefte-de Jong
- Department of Epidemiology, Erasmus MC, Room NA2903, PO Box 2040, 3000, CA, Rotterdam, the Netherlands.
- Department of Global Public Health, Leiden University College, The Hague, the Netherlands.
- Department of Nutrition, Harvard T. H. Chan School of Public Health, Boston, MA, USA.
| | - Yanping Li
- Department of Nutrition, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Mu Chen
- Department of Nutrition, Harvard T. H. Chan School of Public Health, Boston, MA, USA
- Department of Epidemiology, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Gary C Curhan
- Department of Epidemiology, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Josiemer Mattei
- Department of Nutrition, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Vasanti S Malik
- Department of Nutrition, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - John P Forman
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Oscar H Franco
- Department of Epidemiology, Erasmus MC, Room NA2903, PO Box 2040, 3000, CA, Rotterdam, the Netherlands
| | - Frank B Hu
- Department of Nutrition, Harvard T. H. Chan School of Public Health, Boston, MA, USA
- Department of Epidemiology, Harvard T. H. Chan School of Public Health, Boston, MA, USA
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
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Tielemans MJ, Erler NS, Franco OH, Jaddoe VWV, Steegers EAP, Kiefte-de Jong JC. Dietary acid load and blood pressure development in pregnancy: The Generation R Study. Clin Nutr 2017; 37:597-603. [PMID: 28189385 DOI: 10.1016/j.clnu.2017.01.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 01/17/2017] [Accepted: 01/23/2017] [Indexed: 01/08/2023]
Abstract
BACKGROUND & AIMS Dietary intake could induce a mild maternal metabolic acidosis that might lead to a higher level of blood pressure. Because studies in pregnancy are scarce, we evaluated the association between maternal dietary acid load and changes in blood pressure during pregnancy, pregnancy-induced hypertension and pre-eclampsia. METHODS We included 3411 pregnant women of Dutch ancestry from a prospective population-based cohort (Rotterdam, The Netherlands). Dietary data was self-reported via a food-frequency questionnaire in early pregnancy. Four dietary acid load measurements were calculated: dietary potential renal acid load (dPRAL), net endogenous acid production (NEAP), animal protein/potassium ratio, and vegetable protein/potassium ratio. Diastolic blood pressure (DBP) and systolic blood pressure (SBP) were measured three times during pregnancy. Information on pregnancy-induced hypertension and pre-eclampsia was obtained from medical records. Linear mixed models and logistic regression were used and adjusted for sociodemographic and lifestyle factors. RESULTS The results indicated that dPRAL, NEAP and animal protein/potassium ratio were not associated with DBP or SBP in pregnancy. One standard deviation higher vegetable protein/potassium ratio was associated with lower DBP (-0.30 mmHg [95% CI -0.54; -0.06]) but not with SBP (-0.29 mmHg [95% CI -0.60; 0.01]). Dietary acid load measurement was neither associated with the prevalence of pregnancy-induced hypertension nor with pre-eclampsia. CONCLUSIONS Dietary acid load was not associated with changes in DBP or SBP during pregnancy, although women with a higher vegetable protein/potassium ratio had a slightly lower DBP. Dietary acid load was not associated with pregnancy-induced hypertension or pre-eclampsia.
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Affiliation(s)
- Myrte J Tielemans
- Department of Epidemiology, Erasmus MC, University Medical Center, Rotterdam, The Netherlands; The Generation R Study Group, Erasmus MC, University Medical Center, Rotterdam, The Netherlands.
| | - Nicole S Erler
- Department of Epidemiology, Erasmus MC, University Medical Center, Rotterdam, The Netherlands; Department of Biostatistics, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Oscar H Franco
- Department of Epidemiology, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Vincent W V Jaddoe
- Department of Epidemiology, Erasmus MC, University Medical Center, Rotterdam, The Netherlands; The Generation R Study Group, Erasmus MC, University Medical Center, Rotterdam, The Netherlands; Department of Pediatrics, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Eric A P Steegers
- Department of Obstetrics and Gynecology, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Jessica C Kiefte-de Jong
- Department of Epidemiology, Erasmus MC, University Medical Center, Rotterdam, The Netherlands; Department of Pediatrics, Erasmus MC, University Medical Center, Rotterdam, The Netherlands; Leiden University College, The Hague, The Netherlands
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Bergouignan A, Stein TP, Habold C, Coxam V, O’ Gorman D, Blanc S. Towards human exploration of space: The THESEUS review series on nutrition and metabolism research priorities. NPJ Microgravity 2016; 2:16029. [PMID: 28725737 PMCID: PMC5515527 DOI: 10.1038/npjmgrav.2016.29] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 06/30/2016] [Accepted: 07/08/2016] [Indexed: 01/01/2023] Open
Abstract
Nutrition has multiple roles during space flight from providing sufficient nutrients to meet the metabolic needs of the body and to maintain good health, to the beneficial psychosocial aspects related to the meals. Nutrition is central to the functioning of the body; poor nutrition compromises all the physiological systems. Nutrition is therefore likely to have a key role in counteracting the negative effects of space flight (e.g., radiation, immune deficits, oxidative stress, and bone and muscle loss). As missions increase in duration, any dietary/nutritional deficiencies will become progressively more detrimental. Moreover, it has been recognized that the human diet contains, in addition to essential macronutrients, a complex array of naturally occurring bioactive micronutrients that may confer significant long-term health benefits. It is therefore critical that astronauts be adequately nourished during missions. Problems of nutritional origin are often treatable by simply providing the appropriate nutrients and adequate recommendations. This review highlights six key issues that have been identified as space research priorities in nutrition field: in-flight energy balance; altered feeding behavior; development of metabolic stress; micronutrient deficiency; alteration of gut microflora; and altered fluid and electrolytes balance. For each of these topics, relevance for space exploration, knowledge gaps and proposed investigations are described. Finally, the nutritional questions related to bioastronautics research are very relevant to multiple ground-based-related health issues. The potential spin-offs are both interesting scientifically and potentially of great clinical importance.
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Affiliation(s)
- Audrey Bergouignan
- Anschutz Health and Wellness Center, Division of Endocrinology, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA
- Université de Strasbourg, IPHC, Strasbourg, France
- CNRS, UMR7178, Strasbourg, France
| | - T Peter Stein
- Department of Surgery, Rowan University, Stratford, NJ, USA
| | - Caroline Habold
- Université de Strasbourg, IPHC, Strasbourg, France
- CNRS, UMR7178, Strasbourg, France
| | - Veronique Coxam
- Centre de Recherche en Nutrition Humaine d’Auvergne, Clermont-Ferrand, France
| | - Donal O’ Gorman
- Department of Health & Human Performance, Dublin City University, Dublin, Republic of Ireland
| | - Stéphane Blanc
- Université de Strasbourg, IPHC, Strasbourg, France
- CNRS, UMR7178, Strasbourg, France
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Bloomfield SA, Martinez DA, Boudreaux RD, Mantri AV. Microgravity Stress: Bone and Connective Tissue. Compr Physiol 2016; 6:645-86. [PMID: 27065165 DOI: 10.1002/cphy.c130027] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The major alterations in bone and the dense connective tissues in humans and animals exposed to microgravity illustrate the dependency of these tissues' function on normal gravitational loading. Whether these alterations depend solely on the reduced mechanical loading of zero g or are compounded by fluid shifts, altered tissue blood flow, radiation exposure, and altered nutritional status is not yet well defined. Changes in the dense connective tissues and intervertebral disks are generally smaller in magnitude but occur more rapidly than those in mineralized bone with transitions to 0 g and during recovery once back to the loading provided by 1 g conditions. However, joint injuries are projected to occur much more often than the more catastrophic bone fracture during exploration class missions, so protecting the integrity of both tissues is important. This review focuses on the research performed over the last 20 years in humans and animals exposed to actual spaceflight, as well as on knowledge gained from pertinent ground-based models such as bed rest in humans and hindlimb unloading in rodents. Significant progress has been made in our understanding of the mechanisms for alterations in bone and connective tissues with exposure to microgravity, but intriguing questions remain to be solved, particularly with reference to biomedical risks associated with prolonged exploration missions.
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Affiliation(s)
- Susan A Bloomfield
- Department of Health & Kinesiology, Texas A&M University, College Station, Texas, USA
| | - Daniel A Martinez
- Department of Mechanical Engineering, University of Houston, Houston, Texas, USA
| | - Ramon D Boudreaux
- Biomedical Engineering, Texas A&M University, College Station, Texas, USA
| | - Anita V Mantri
- Department of Health & Kinesiology, Texas A&M University, College Station, Texas, USA.,Health Science Center School of Medicine, Texas A&M University, College Station, Texas, USA
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Hackney KJ, Scott JM, Hanson AM, English KL, Downs ME, Ploutz-Snyder LL. The Astronaut-Athlete. J Strength Cond Res 2015; 29:3531-45. [DOI: 10.1519/jsc.0000000000001191] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Smith SM, Castaneda-Sceppa C, O'Brien KO, Abrams SA, Gillman P, Brooks NE, Cloutier GJ, Heer M, Zwart SR, Wastney ME. Calcium kinetics during bed rest with artificial gravity and exercise countermeasures. Osteoporos Int 2014; 25:2237-44. [PMID: 24861908 PMCID: PMC4521405 DOI: 10.1007/s00198-014-2754-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Accepted: 05/15/2014] [Indexed: 10/25/2022]
Abstract
UNLABELLED We assessed the potential for countermeasures to lessen the loss of bone calcium during bed rest. Subjects ingested less calcium during bed rest, and with artificial gravity, they also absorbed less calcium. With exercise, they excreted less calcium. To retain bone during bed rest, calcium intake needs to be maintained. INTRODUCTION This study aims to assess the potential for artificial gravity (AG) and exercise (EX) to mitigate loss of bone calcium during space flight. METHODS We performed two studies: (1) a 21-day bed rest (BR) study with subjects receiving 1 h/day AG (n = 8) or no AG (n = 7) and (2) a 28-day BR study with 1 h/day resistance EX (n = 10) or no EX (n = 3). In both studies, stable isotopes of Ca were administered orally and intravenously, at baseline and after 10 days of BR, and blood, urine, and feces were sampled for up to 14 days post dosing. Tracers were measured using thermal ionization mass spectrometry. Data were analyzed by compartmental modeling. RESULTS Less Ca was absorbed during BR, resulting in lower Ca balance in BR+AG (-6.04 ± 3.38 mmol/day, P = 0.023). However, Ca balance did not change with BR+EX, even though absorbed Ca decreased and urinary Ca excretion increased, because endogenous excretion decreased, and there was a trend for increased bone deposition (P = 0.06). Urinary N-telopeptide excretion increased in controls during BR, but not in the EX group. Markers of bone formation were not different between treatment groups for either study. Ca intake decreased during BR (by 5.4 mmol/day in the AG study and 2.8 mmol/day in the EX study), resulting in lower absorbed Ca. CONCLUSIONS During BR (or space flight), Ca intake needs to be maintained or even increased with countermeasures such as exercise, to enable maintenance of bone Ca.
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Affiliation(s)
- S M Smith
- NASA Lyndon B. Johnson Space Center, Attn: Mail Code SK3, 2101 NASA Parkway, Houston, TX, 77058, USA,
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English KL, Loehr JA, Lee SMC, Smith SM. Early-phase musculoskeletal adaptations to different levels of eccentric resistance after 8 weeks of lower body training. Eur J Appl Physiol 2014; 114:2263-80. [PMID: 25048074 DOI: 10.1007/s00421-014-2951-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Accepted: 06/29/2014] [Indexed: 10/25/2022]
Abstract
PURPOSE Eccentric muscle actions are important to the development of muscle mass and strength and may affect bone mineral density (BMD). This study's purpose was to determine the relative effectiveness of five different eccentric:concentric load ratios to increase musculoskeletal parameters during early adaptations to resistance training. METHODS Forty male subjects performed a supine leg press and calf press training program 3 days week(-1) for 8 weeks. Subjects were matched for pre-training leg press 1-repetition maximum strength (1-RM) and randomly assigned to one of five training groups. Concentric training load (% 1-RM) was constant across groups, but within groups, eccentric load was 0, 33, 66, 100, or 138% of concentric load. Muscle mass (dual energy X-ray absorptiometry; DXA), strength (1-RM), and BMD (DXA) were measured pre- and post-training. Markers of bone metabolism were assessed pre-, mid- and post-training. RESULTS The increase in leg press 1-RM in the 138% group (20 ± 4%) was significantly greater (P < 0.05) than the 0% (8 ± 3%), 33% (8 ± 5%) and 66% (8 ± 4%) groups, but not the 100% group (13 ± 6 %; P = 0.15). All groups, except the 0% group, increased calf press 1-RM (P < 0.05). Leg lean mass and greater trochanter BMD were increased only in the 138% group (P < 0.05). CONCLUSIONS Early-phase adaptations to eccentric overload training include increases in muscle mass and site-specific increases in BMD and muscle strength which are not present or are less with traditional and eccentric underload training. Eccentric overload provides a robust musculoskeletal stimulus that may benefit bedridden patients, individuals recovering from injury or illness, and astronauts during spaceflight.
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Affiliation(s)
- Kirk L English
- JES Tech, LLC, 16870 Royal Crest Dr., Houston, TX, 77058, USA,
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Hackney KJ, English KL. Protein and Essential Amino Acids to Protect Musculoskeletal Health during Spaceflight: Evidence of a Paradox? Life (Basel) 2014; 4:295-317. [PMID: 25370374 PMCID: PMC4206848 DOI: 10.3390/life4030295] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 06/19/2014] [Accepted: 06/23/2014] [Indexed: 11/17/2022] Open
Abstract
Long-duration spaceflight results in muscle atrophy and a loss of bone mineral density. In skeletal muscle tissue, acute exercise and protein (e.g., essential amino acids) stimulate anabolic pathways (e.g., muscle protein synthesis) both independently and synergistically to maintain neutral or positive net muscle protein balance. Protein intake in space is recommended to be 12%-15% of total energy intake (≤1.4 g∙kg-1∙day-1) and spaceflight is associated with reduced energy intake (~20%), which enhances muscle catabolism. Increasing protein intake to 1.5-2.0 g∙kg-1∙day-1 may be beneficial for skeletal muscle tissue and could be accomplished with essential amino acid supplementation. However, increased consumption of sulfur-containing amino acids is associated with increased bone resorption, which creates a dilemma for musculoskeletal countermeasures, whereby optimizing skeletal muscle parameters via essential amino acid supplementation may worsen bone outcomes. To protect both muscle and bone health, future unloading studies should evaluate increased protein intake via non-sulfur containing essential amino acids or leucine in combination with exercise countermeasures and the concomitant influence of reduced energy intake.
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Affiliation(s)
- Kyle J Hackney
- Department of Health, Nutrition, and Exercise Sciences, North Dakota State University, Fargo, ND 58102, USA.
| | - Kirk L English
- Exercise Physiology and Countermeasures Laboratory, JES Tech, Houston, TX 77058, USA.
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Lane HW, Bourland C, Barrett A, Heer M, Smith SM. The role of nutritional research in the success of human space flight. Adv Nutr 2013; 4:521-3. [PMID: 24038244 PMCID: PMC3771136 DOI: 10.3945/an.113.004101] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The United States has had human space flight programs for >50 y and has had a continued presence in space since 2000. Providing nutritious and safe food is imperative for astronauts because space travelers are totally dependent on launched food. Space flight research topics have included energy, protein, nutritional aspects of bone and muscle health, and vision issues related to 1-carbon metabolism. Research has shown that energy needs during flight are similar to energy needs on Earth. Low energy intakes affect protein turnover. The type of dietary protein is also important for bone health, plant-based protein being more efficacious than animal protein. Bone loss is greatly ameliorated with adequate intakes of energy and vitamin D, along with routine resistive exercise. Astronauts with lower plasma folate concentrations may be more susceptible to vision changes. Foods for space flight were developed initially by the U.S. Air Force School of Aerospace Medicine in conjunction with the U.S. Army Natick Laboratories and NASA. Hazard Analysis Critical Control Point safety standards were specifically developed for space feeding. Prepackaged foods for the International Space Station were originally high in sodium (5300 mg/d), but NASA has recently reformulated >90 foods to reduce sodium intake to 3000 mg/d. Food development has improved nutritional quality as well as safety and acceptability.
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Affiliation(s)
- Helen W. Lane
- Human Health and Performance Directorate, NASA Lyndon B. Johnson Space Center, Houston, TX,To whom correspondence should be sent: E-mail:
| | | | - Ann Barrett
- Combat Feeding Directorate, U.S. Army Natick Soldier Research, Development and Engineering Center, Natick, MA
| | - Martina Heer
- Profil, Neuss, Germany; and Department of Food and Nutrition Sciences, University of Bonn, Bonn, Germany
| | - Scott M. Smith
- Human Health and Performance Directorate, NASA Lyndon B. Johnson Space Center, Houston, TX
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27
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Smith S, Rice B, Dlouhy H, Zwart S. Assessment of Nutritional Intake During Space Flight and Space Flight Analogs. ACTA ACUST UNITED AC 2013. [DOI: 10.1016/j.profoo.2013.04.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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Trinchieri A. A rapid food screener ranks potential renal acid load of renal stone formers similarly to a diet history questionnaire. Urolithiasis 2012; 41:3-7. [DOI: 10.1007/s00240-012-0522-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2012] [Accepted: 12/08/2012] [Indexed: 11/24/2022]
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Smith SM, McCoy T, Gazda D, Morgan JLL, Heer M, Zwart SR. Space flight calcium: implications for astronaut health, spacecraft operations, and Earth. Nutrients 2012; 4:2047-68. [PMID: 23250146 PMCID: PMC3546622 DOI: 10.3390/nu4122047] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Revised: 11/13/2012] [Accepted: 12/10/2012] [Indexed: 11/21/2022] Open
Abstract
The space flight environment is known to induce bone loss and, subsequently, calcium loss. The longer the mission, generally the more bone and calcium are lost. This review provides a history of bone and calcium studies related to space flight and highlights issues related to calcium excretion that the space program must consider so that urine can be recycled. It also discusses a novel technique using natural stable isotopes of calcium that will be helpful in the future to determine calcium and bone balance during space flight.
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Affiliation(s)
- Scott M. Smith
- Human Health and Performance Directorate, NASA Lyndon B. Johnson Space Center, Houston, TX 77058, USA; E-Mail:
| | - Torin McCoy
- Human Health and Performance Directorate, NASA Lyndon B. Johnson Space Center, Houston, TX 77058, USA; E-Mail:
| | - Daniel Gazda
- Wyle Science, Technology & Engineering Group, Houston, TX 77058, USA; E-Mail:
| | - Jennifer L. L. Morgan
- Oak Ridge Associated Universities/NASA Post-Doctoral Fellow, NASA Lyndon B. Johnson Space Center, Houston, TX 77058, USA; E-Mail:
| | - Martina Heer
- Profil, 41460 Neuss, Germany; E-Mail:
- University of Bonn, 53115 Bonn, Germany
| | - Sara R. Zwart
- Division of Space Life Sciences, Universities Space Research Association, Houston, TX 77058, USA; E-Mail:
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Zhang L, Curhan GC, Forman JP. Diet-dependent net acid load and risk of incident hypertension in United States women. Hypertension 2009; 54:751-5. [PMID: 19667248 DOI: 10.1161/hypertensionaha.109.135582] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Animal and human studies suggest a potential link between acid-base status and blood pressure. Contemporary Western diets yield a daily systemic acid load of varying amounts, yet the association with hypertension has never been explored. We prospectively examined the association between the diet-dependent net acid load (also known as the estimated net endogenous acid production) and the risk of incident hypertension among 87 293 women without a history of hypertension in the Nurses' Health Study II. We also used the ratio of animal protein intake to potassium intake as an alternative evaluation of diet-dependent net acid load. We identified 15 385 incident cases of hypertension during 995 239 person-years of follow-up. After adjusting for potential confounders, women in the top decile of estimated diet-dependent net acid load had an increased risk of hypertension (relative risk: 1.14; 95% CI: 1.05 to 1.24; P for trend=0.01) compared with women in the bottom decile. To test whether the association between estimated diet-dependent net acid load and hypertension is independent of its individual components, an additional adjustment for intakes of protein and potassium was made and resulted in a relative risk of 1.23 (95% CI: 1.08 to 1.41; P for trend=0.003) for the top decile of estimated diet-dependent net acid load. Results of the ratio of animal protein intake to potassium intake were similar with those of estimated diet-depend net acid load. In conclusion, a high diet-dependent net acid load is independently associated with a higher risk of incident hypertension.
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Affiliation(s)
- Luxia Zhang
- Channing Laboratory/Renal Division, Brigham and Women's Hospital, 181 Longwood Ave., Boston, MA 02115, USA.
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31
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Hooshmand S, Arjmandi BH. Viewpoint: dried plum, an emerging functional food that may effectively improve bone health. Ageing Res Rev 2009; 8:122-7. [PMID: 19274852 DOI: 10.1016/j.arr.2009.01.002] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Osteoporosis is a debilitating disorder that affects both female and male, albeit to a greater extent in women than men. As the demographic shift to a more aged population continues, a growing number of men and women will be afflicted with osteoporosis and a search for potential non-pharmacological alternative therapies for osteoporosis is of prime interest. Aside from existing drug therapies, certain lifestyle and nutritional factors are known to reduce the risk of osteoporosis. Among nutritional factors, recent observations suggest that dried plum, or prunes (Prunus domestica L.) is the most effective fruit in both preventing and reversing bone loss. Animal studies and a 3-month clinical trial conducted in our laboratories have shown that dried plum has positive effects on bone indices. The animal data indicate that dried plum not only protects against but more importantly reverses bone loss in two separate models of osteopenia. Our initial animal study indicated that dried plum prevented the ovariectomy-induced reduction in bone mineral density (BMD) of the femur and lumbar vertebra. In another study, to mimic established osteoporosis, rats were ovariectomized and allowed to lose bone before the initiation of treatment. Dried plum as low as 5% (w/w) restored BMD to the level of intact rats. More importantly, dried plum reversed the loss of trabecular architectural properties such as trabecular number and connectivity density, and trabecular separation. We have also shown the effectiveness of dried plum in reversal of bone loss due to skeletal unloading. Analysis of BMD and trabecular bone structure by microcomputed tomography (microCT) revealed that dried plum enhanced bone recovery during reambulation following skeletal unloading and had comparable effects to parathyroid hormone. In addition to the animal studies, our 3-month clinical trial indicated that the consumption of dried plum daily by postmenopausal women significantly increased serum markers of bone formation, total alkaline phosphatase, bone-specific alkaline phosphatase and insulin-like growth factor-I by 12, 6, and 17%, respectively. This review summarizes the findings of studies published to date which examine the beneficial effects of dried plum on bone in both female and male animal models of osteoporosis as well as the only published clinical study.
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Affiliation(s)
- Shirin Hooshmand
- Department of Nutrition, Food & Exercise Sciences, Florida State University, Tallahassee, FL 32306, USA
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Smith SM, Zwart SR, Heer MA, Baecker N, Evans HJ, Feiveson AH, Shackelford LC, Leblanc AD. Effects of artificial gravity during bed rest on bone metabolism in humans. J Appl Physiol (1985) 2008; 107:47-53. [PMID: 19074572 DOI: 10.1152/japplphysiol.91134.2008] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We report results from a study designed to explore the utility of artificial gravity (AG) as a countermeasure to bone loss induced by microgravity simulation. After baseline testing, 15 male subjects underwent 21 days of 6 degrees head-down bed rest to simulate the deconditioning associated with spaceflight. Eight of the subjects underwent 1 h of centrifugation (AG; 1 G(z) at the heart, 2.5 G(z) at the feet) each day for 21 days, whereas seven of the subjects served as untreated controls (Con). Blood and urine were collected before, during, and after bed rest for bone marker determinations. Bone mineral density (BMD) and bone mineral content (BMC) were determined by dual-energy X-ray absorptiometry and peripheral quantitative computerized tomography before and after bed rest. Urinary excretion of bone resorption markers increased during bed rest, but the AG and Con groups did not differ significantly. The same was true for serum C-telopeptide. During bed rest, bone alkaline phosphatase (ALP) and total ALP tended to be lower in the AG group (P = 0.08, P = 0.09). Neither BMC nor BMD changed significantly from the pre-bed rest period in AG or Con groups, and the two groups were not significantly different. However, when AG and Con data were combined, there was a significant (P < 0.05) effect of time for whole body total BMC and total hip and trochanter BMD. These data failed to demonstrate efficacy of this AG prescription to prevent the changes in bone metabolism observed during 3 wk of bed rest.
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Affiliation(s)
- S M Smith
- Human Adaptation and Countermeasures Division, NASA Johnson Space Center, Houston, TX 77058, USA.
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Abstract
As we approach the end of the first 50 years of human space travel, much has been learned about adaptation to microgravity and the risks associated with extended-duration space exploration. As the frequency and duration of flights grew, nutrition issues became more critical and the questions to be answered became more complex: What are the nutrient requirements for space travelers? Can nutrients be used as tools to mitigate the negative effects of space travel on humans? How does nutrition interrelate with other physiological systems (such as muscle, bone, and cardiovascular system) and their adaptation to microgravity? Much research has been done over the decades in both actual spaceflight and ground-based analogs. We review here much of what is known, and highlight areas of ongoing research and concerns for future exploration of the Moon, Mars, and beyond.
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Affiliation(s)
- Scott M Smith
- Human Adaptation and Countermeasures Division, National Aeronautics and Space Administration, Johnson Space Center, Houston, Texas 77058, USA
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Smith SM, Zwart SR, Heer M, Lee SMC, Baecker N, Meuche S, Macias BR, Shackelford LC, Schneider S, Hargens AR. WISE-2005: supine treadmill exercise within lower body negative pressure and flywheel resistive exercise as a countermeasure to bed rest-induced bone loss in women during 60-day simulated microgravity. Bone 2008; 42:572-81. [PMID: 18249055 DOI: 10.1016/j.bone.2007.11.015] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2007] [Revised: 11/16/2007] [Accepted: 11/29/2007] [Indexed: 11/19/2022]
Abstract
Bone loss associated with disuse during bed rest (BR), an analog of space flight, can be attenuated by exercise. In previous studies, the efficacy of either aerobic or resistive exercise countermeasures has been examined separately. We hypothesized that a regimen of combined resistive and aerobic exercise during BR would prevent bone resorption and promote bone formation. After a 20-day ambulatory adaptation to controlled confinement and diet, 16 women participated in a 60-day, 6 degrees head-down-tilt BR and were assigned randomly to one of the two groups. Control subjects (CON, n=8) performed no countermeasure. Exercise subjects (EX, n=8) participated in an exercise program during BR, alternating between supine treadmill exercise within lower body negative pressure (3-4 d wk(-1)) and flywheel resistive exercise (2-3 d wk(-1)). By the last week of BR, excretion of helical peptide (CON, 79%+/-44 increase; EX, 64%+/-50, mean+/-SD) and N-terminal cross-linking telopeptide (CON, 51%+/-34; EX, 43%+/-56), markers of bone resorption, were greater than they were before BR in both groups (P<0.05). However, serum concentrations of the bone formation marker procollagen type I N propeptide were greater in EX than CON throughout and after bed rest (P<0.05), while concentrations of the bone formation marker bone alkaline phosphatase tended to be greater in EX than CON. Dual-energy X-ray absorptiometry results indicated that the exercise treatment significantly (P<0.05) attenuated loss of hip and leg bone mineral density in EX compared to CON. The combination of resistive and aerobic exercise did not prevent bone resorption but did promote bone formation, and helped mitigate the net bone loss associated with simulated microgravity.
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Affiliation(s)
- Scott M Smith
- Human Adaptation and Countermeasures Division, National Aeronautics and Space Administration Lyndon B. Johnson Space Center, Houston, TX 77058, USA.
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Pavy-Le Traon A, Heer M, Narici MV, Rittweger J, Vernikos J. From space to Earth: advances in human physiology from 20 years of bed rest studies (1986-2006). Eur J Appl Physiol 2007; 101:143-94. [PMID: 17661073 DOI: 10.1007/s00421-007-0474-z] [Citation(s) in RCA: 381] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/13/2007] [Indexed: 01/11/2023]
Abstract
Bed rest studies of the past 20 years are reviewed. Head-down bed rest (HDBR) has proved its usefulness as a reliable simulation model for the most physiological effects of spaceflight. As well as continuing to search for better understanding of the physiological changes induced, these studies focused mostly on identifying effective countermeasures with encouraging but limited success. HDBR is characterised by immobilization, inactivity, confinement and elimination of Gz gravitational stimuli, such as posture change and direction, which affect body sensors and responses. These induce upward fluid shift, unloading the body's upright weight, absence of work against gravity, reduced energy requirements and reduction in overall sensory stimulation. The upward fluid shift by acting on central volume receptors induces a 10-15% reduction in plasma volume which leads to a now well-documented set of cardiovascular changes including changes in cardiac performance and baroreflex sensitivity that are identical to those in space. Calcium excretion is increased from the beginning of bed rest leading to a sustained negative calcium balance. Calcium absorption is reduced. Body weight, muscle mass, muscle strength is reduced, as is the resistance of muscle to insulin. Bone density, stiffness of bones of the lower limbs and spinal cord and bone architecture are altered. Circadian rhythms may shift and are dampened. Ways to improve the process of evaluating countermeasures--exercise (aerobic, resistive, vibration), nutritional and pharmacological--are proposed. Artificial gravity requires systematic evaluation. This review points to clinical applications of BR research revealing the crucial role of gravity to health.
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Affiliation(s)
- A Pavy-Le Traon
- Service D'explorations Fonctionnelles Respiratoires Et d'analyses Physiologiques, Hopital La Cavale Blanche, University Hospital of Brest, 29609, Brest Cedex, France.
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Zwart SR, Hargens AR, Lee SMC, Macias BR, Watenpaugh DE, Tse K, Smith SM. Lower body negative pressure treadmill exercise as a countermeasure for bed rest-induced bone loss in female identical twins. Bone 2007; 40:529-37. [PMID: 17070743 PMCID: PMC1876821 DOI: 10.1016/j.bone.2006.09.014] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2006] [Revised: 09/07/2006] [Accepted: 09/12/2006] [Indexed: 10/24/2022]
Abstract
Supine weight-bearing exercise within lower body negative pressure (LBNP) alleviates some of the skeletal deconditioning induced by simulated weightlessness in men. We examined this potential beneficial effect in women. Because dietary acid load affected the degree of bone resorption in men during bed rest, we also investigated this variable in women. Subjects were 7 pairs of female identical twins assigned at random to 2 groups, sedentary bed rest (control) or bed rest with supine treadmill exercise within LBNP. Dietary intake was controlled and monitored. Urinary calcium and markers of bone resorption were measured before bed rest and on bed rest days 5/6, 12/13, 19/20, and 26/27. Bone mineral content was assessed by dual-energy X-ray absorptiometry before and after bed rest. Data were analyzed by repeated-measures two-way analysis of variance. Pearson correlation coefficients were used to define the relationships between diet and markers of bone metabolism and to estimate heritability of markers. During bed rest, all markers of bone resorption and urinary calcium and phosphorus increased (P<0.001); parathyroid hormone (P=0.06), bone-specific alkaline phosphatase (P=0.06), and 1,25-dihydroxyvitamin D (P=0.09) tended to decrease. LBNP exercise tended to mitigate bone density loss. The ratio of dietary animal protein to potassium was positively correlated with urinary calcium excretion for all weeks of bed rest in the control group, but only during weeks 1 and 3 in the exercise group. Pre-bed rest data suggested that many markers of bone metabolism have strong genetic determinants. Treadmill exercise within LBNP had less of a protective effect on bone resorption during bed rest in women than previously published results had shown for its effect in men, but the same trends were observed for both sexes. Dietary acid load of these female subjects was significantly correlated with calcium excretion but not with other bone resorption markers.
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Affiliation(s)
- Sara R. Zwart
- Universities Space Research Association, Houston, Texas, USA 77058
| | - Alan R. Hargens
- Department of Orthopaedic Surgery, University of California, San Diego, UCSD Medical Center, San Diego, California, USA 92103
| | | | - Brandon R. Macias
- Department of Orthopaedic Surgery, University of California, San Diego, UCSD Medical Center, San Diego, California, USA 92103
| | - Donald E. Watenpaugh
- Department of Integrative Physiology, University of North Texas Health Sciences Center, Fort Worth, Texas, USA 76104
| | - Kevin Tse
- Department of Orthopaedic Surgery, University of California, San Diego, UCSD Medical Center, San Diego, California, USA 92103
| | - Scott M. Smith
- Human Adaptation and Countermeasures Office, National Aeronautics and Space Administration Lyndon B. Johnson Space Center, Houston, Texas, USA 77058
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Winzenberg TM, Shaw K, Fryer J, Jones G. Calcium supplementation for improving bone mineral density in children. Cochrane Database Syst Rev 2006; 2006:CD005119. [PMID: 16625624 PMCID: PMC8865374 DOI: 10.1002/14651858.cd005119.pub2] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Clinical trials have shown that calcium supplementation in children can increase bone mineral density (BMD) although this effect may not be maintained. There has been no quantitative systematic review of this intervention. OBJECTIVES . To determine the effectiveness of calcium supplementation for improving BMD in children. . To determine if any effect varies by sex, pubertal stage, ethnicity or level of physical activity, and if any effect persists after supplementation is ceased. SEARCH STRATEGY We searched CENTRAL, (Cochrane Central Register of Controlled Trials) (Issue 3, 2005), MEDLINE (1966 to 1 April 2005), EMBASE (1980 to 1 April 2005), CINAHL (1982 to 1 April 2005), AMED (1985 to 1 April 2005), MANTIS (1880 to 1 April 2005) ISI Web of Science (1945 to 1 April 2005), Food Science and Technology Abstracts (1969 to 1 April 2005) and Human Nutrition (1982 to 1 April 2005). Conference abstract books (Osteoporosis International, Journal of Bone and Mineral Research) were hand-searched. SELECTION CRITERIA Randomised controlled trials of calcium supplementation (including by food sources) compared with placebo, with a treatment period of at least 3 months in children without co-existent medical conditions affecting bone metabolism. Outcomes had to include areal or volumetric BMD, bone mineral content (BMC), or in the case of studies using quantitative ultrasound, broadband ultrasound attenuation and ultrasonic speed of sound, measured after at least 6 months of follow-up. DATA COLLECTION AND ANALYSIS Two authors independently assessed trial quality and extracted data including adverse events. We contacted study authors for additional information. MAIN RESULTS The 19 trials included 2859 participants, of which 1367 were randomised to supplementation and 1426 to placebo. There was no heterogeneity in the results of the main effects analyses to suggest that the studies were not comparable. There was no effect of calcium supplementation on femoral neck or lumbar spine BMD. There was a small effect on total body BMC (standardised mean difference (SMD) +0.14, 95% CI+0.01, +0.27) and upper limb BMD (SMD +0.14, 95%CI +0.04, +0.24). Only the effect in the upper limb persisted after supplementation ceased (SMD+0.14, 95%CI+0.01, +0.28). This effect is approximately equivalent to a 1.7% greater increase in supplemented groups, which at best would reduce absolute fracture risk in children by 0.1-0.2%per annum. There was no evidence of effect modification by baseline calcium intake, sex, ethnicity, physical activity or pubertal stage. Adverse events were reported infrequently and were minor. AUTHORS' CONCLUSIONS While there is a small effect of calcium supplementation in the upper limb, the increase in BMD which results is unlikely to result in a clinically significant decrease in fracture risk. The results do not support the use of calcium supplementation in healthy children as a public health intervention. These results cannot be extrapolated to children with medical conditions affecting bone metabolism.
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Affiliation(s)
- T M Winzenberg
- University of Tasmania, Menzies Resarch Institute, Private Bag 23, Hobart, TAS, Australia, 7001.
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Zwart SR, Davis-Street JE, Paddon-Jones D, Ferrando AA, Wolfe RR, Smith SM. Amino acid supplementation alters bone metabolism during simulated weightlessness. J Appl Physiol (1985) 2005; 99:134-40. [PMID: 15691900 DOI: 10.1152/japplphysiol.01406.2004] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
High-protein and acidogenic diets induce hypercalciuria. Foods or supplements with excess sulfur-containing amino acids increase endogenous sulfuric acid production and therefore have the potential to increase calcium excretion and alter bone metabolism. In this study, effects of an amino acid/carbohydrate supplement on bone resorption were examined during bed rest. Thirteen subjects were divided at random into two groups: a control group (Con, n = 6) and an amino acid-supplemented group (AA, n = 7) who consumed an extra 49.5 g essential amino acids and 90 g carbohydrate per day for 28 days. Urine was collected for n-telopeptide (NTX), deoxypyridinoline (DPD), calcium, and pH determinations. Bone mineral content was determined and potential renal acid load was calculated. Bone-specific alkaline phosphatase was measured in serum samples collected on day 1 (immediately before bed rest) and on day 28. Potential renal acid load was higher in the AA group than in the Con group during bed rest ( P < 0.05). For all subjects, during bed rest urinary NTX and DPD concentrations were greater than pre-bed rest levels ( P < 0.05). Urinary NTX and DPD tended to be higher in the AA group ( P = 0.073 and P = 0.056, respectively). During bed rest, urinary calcium was greater than baseline levels ( P < 0.05) in the AA group but not the Con group. Total bone mineral content was lower after bed rest than before bed rest in the AA group but not the Con group ( P < 0.05). During bed rest, urinary pH decreased ( P < 0.05), and it was lower in the AA group than the Con group. These data suggest that bone resorption increased, without changes in bone formation, in the AA group.
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Affiliation(s)
- S R Zwart
- Human Adaptation and Countermeasures Office, NASA Lyndon B. Johnson Space Center, Houston, TX 77058, USA
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