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Volek JS, Kackley ML, Buga A. Nutritional Considerations During Major Weight Loss Therapy: Focus on Optimal Protein and a Low-Carbohydrate Dietary Pattern. Curr Nutr Rep 2024; 13:422-443. [PMID: 38814519 PMCID: PMC11327213 DOI: 10.1007/s13668-024-00548-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/01/2024] [Indexed: 05/31/2024]
Abstract
PURPOSE OF REVIEW Considering the high prevalence of obesity and related metabolic impairments in the population, the unique role nutrition has in weight loss, reversing metabolic disorders, and maintaining health cannot be overstated. Normal weight and well-being are compatible with varying dietary patterns, but for the last half century there has been a strong emphasis on low-fat, low-saturated fat, high-carbohydrate based approaches. Whereas low-fat dietary patterns can be effective for a subset of individuals, we now have a population where the vast majority of adults have excess adiposity and some degree of metabolic impairment. We are also entering a new era with greater access to bariatric surgery and approval of anti-obesity medications (glucagon-like peptide-1 analogues) that produce substantial weight loss for many people, but there are concerns about disproportionate loss of lean mass and nutritional deficiencies. RECENT FINDINGS No matter the approach used to achieve major weight loss, careful attention to nutritional considerations is necessary. Here, we examine the recent findings regarding the importance of adequate protein to maintain lean mass, the rationale and evidence supporting low-carbohydrate and ketogenic dietary patterns, and the potential benefits of including exercise training in the context of major weight loss. While losing and sustaining weight loss has proven challenging, we are optimistic that application of emerging nutrition science, particularly personalized well-formulated low-carbohydrate dietary patterns that contain adequate protein (1.2 to 2.0 g per kilogram reference weight) and achieve the beneficial metabolic state of euketonemia (circulating ketones 0.5 to 5 mM), is a promising path for many individuals with excess adiposity.
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Affiliation(s)
- Jeff S Volek
- Department of Human Sciences, The Ohio State University, 305 Annie & John Glenn Ave, Columbus, OH, 43210, USA.
| | - Madison L Kackley
- Department of Human Sciences, The Ohio State University, 305 Annie & John Glenn Ave, Columbus, OH, 43210, USA
| | - Alex Buga
- Department of Human Sciences, The Ohio State University, 305 Annie & John Glenn Ave, Columbus, OH, 43210, USA
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2
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Soto-Mota A, Jansen LT, Norwitz NG, Pereira MA, Ebbeling CB, Ludwig DS. Physiologic Adaptation to Macronutrient Change Distorts Findings from Short Dietary Trials: Reanalysis of a Metabolic Ward Study. J Nutr 2024; 154:1080-1086. [PMID: 38128881 DOI: 10.1016/j.tjnut.2023.12.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 12/06/2023] [Accepted: 12/12/2023] [Indexed: 12/23/2023] Open
Abstract
An influential 2-wk cross-over feeding trial without a washout period purported to show advantages of a low-fat diet (LFD) compared with a low-carbohydrate diet (LCD) for weight control. In contrast to several other macronutrient trials, the diet order effect was originally reported as not significant. In light of a new analysis by the original investigative group identifying an order effect, we aimed to examine, in a reanalysis of publicly available data (16 of 20 original participants; 7 female; mean BMI, 27.8 kg/m2), the validity of the original results and the claims that trial data oppose the carbohydrate-insulin model of obesity (CIM). We found that energy intake on the LCD was much lower when this diet was consumed first compared with second (a difference of -1164 kcal/d, P = 3.6 × 10-13); the opposite pattern was observed for the LFD (924 kcal/d, P = 2.0 × 10-16). This carry-over effect was significant (P interaction = 0.0004) whereas the net dietary effect was not (P = 0.4). Likewise, the between-arm difference (LCD - LFD) was -320 kcal/d in the first period and +1771 kcal/d in the second. Body fat decreased with consumption of the LCD first and increased with consumption of this diet second (-0.69 ± 0.33 compared with 0.57 ± 0.32 kg, P = 0.007). LCD-first participants had higher β-hydroxybutyrate levels while consuming the LCD and lower respiratory quotients while consuming LFD when compared with LFD-first participants on their respective diets. Change in insulin secretion as assessed by C-peptide in the first diet period predicted higher energy intake and less fat loss in the second period. These findings, which tend to support rather than oppose the CIM, suggest that differential (unequal) carry-over effects and short duration, with no washout period, preclude causal inferences regarding chronic macronutrient effects from this trial.
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Affiliation(s)
- Adrian Soto-Mota
- Metabolic Diseases Research Unit. National Institute of Medical Sciences and Nutrition Salvador Zubiran. Mexico City, Mexico; Tecnologico de Monterrey. School of Medicine. Mexico City, Mexico
| | - Lisa T Jansen
- Department of Dietetics & Nutrition, University of Arkansas for Medical Sciences, Little Rock, AR, United States; Arkansas Children's Nutrition Center, Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | | | - Mark A Pereira
- Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, MN, United States
| | - Cara B Ebbeling
- Harvard Medical School, Boston, MA, United States; New Balance Foundation Obesity Prevention Center, Boston Children's Hospital, Boston MA, United States
| | - David S Ludwig
- Harvard Medical School, Boston, MA, United States; New Balance Foundation Obesity Prevention Center, Boston Children's Hospital, Boston MA, United States; Department of Nutrition, Exercise and Sports, University of Copenhagen.
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3
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Ludwig DS. Carbohydrate-insulin model: does the conventional view of obesity reverse cause and effect? Philos Trans R Soc Lond B Biol Sci 2023; 378:20220211. [PMID: 37661740 PMCID: PMC10475871 DOI: 10.1098/rstb.2022.0211] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Accepted: 07/18/2023] [Indexed: 09/05/2023] Open
Abstract
Conventional obesity treatment, based on the First Law of Thermodynamics, assumes that excess body fat gain is driven by overeating, and that all calories are metabolically alike in this regard. Hence, to lose weight one must ultimately eat less and move more. However, this prescription rarely succeeds over the long term, in part because calorie restriction elicits predictable biological responses that oppose ongoing weight loss. The carbohydrate-insulin model posits the opposite causal direction: overeating doesn't drive body fat increase; instead, the process of storing excess fat drives overeating. A diet high in rapidly digestible carbohydrates raises the insulin-to-glucagon ratio, shifting energy partitioning towards storage in adipose, leaving fewer calories for metabolically active and fuel sensing tissues. Consequently, hunger increases, and metabolic rate slows in the body's attempt to conserve energy. A small shift in substrate partitioning though this mechanism could account for the slow but progressive weight gain characteristic of common forms of obesity. From this perspective, the conventional calorie-restricted, low-fat diet amounts to symptomatic treatment, failing to target the underlying predisposition towards excess fat deposition. A dietary strategy to lower insulin secretion may increase the effectiveness of long-term weight management and chronic disease prevention. This article is part of a discussion meeting issue 'Causes of obesity: theories, conjectures and evidence (Part II)'.
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Affiliation(s)
- David S. Ludwig
- New Balance Foundation Obesity Prevention Center, Boston Children's Hospital, Boston, MA 02115, USA
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Martins C, Nymo S, Aukan MI, Roekenes JA, Coutinho SR, Hunter GR, Gower BA. Association between ß-Hydroxybutyrate Plasma Concentrations after Hypocaloric Ketogenic Diets and Changes in Body Composition. J Nutr 2023; 153:1944-1949. [PMID: 37182692 DOI: 10.1016/j.tjnut.2023.05.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 05/05/2023] [Accepted: 05/10/2023] [Indexed: 05/16/2023] Open
Abstract
BACKGROUND Early studies show that ketogenic diets (KDs) lead to preferential loss of fat mass (FM), whereas preserving fat-free mass (FFM). Additionally, animal data support the anticatabolic effects of DL-3-hydroxybutyrate. From our knowledge, a potential association between ß-hydroxybutyrate (ßHB) plasma concentrations and changes in body composition has never been explored. OBJECTIVES The main aim of this analysis was to determine if ßHB plasma concentrations, following hypocaloric KDs, were associated with FM and FFM changes in men and women with obesity. METHODS Data from 199 individuals (BMI = 36.6 ± 4.3 kg/m2; age = 43.6 ± 9.8 y; 82 men) were collated from 3 weight loss studies employing common measures of body composition (air displacement plethysmography) and ßHB plasma concentration (ELISA). The association between ßHB and weight, FM and FFM loss (kg), and %FFM loss (%FFML) was investigated with Spearman correlation. Multivariable linear regression was used to determine if ßHB was a significant predictor of the changes in anthropometric variables, after adjusting for confounding factors. RESULTS ßHB was not associated with FFML (% or kg), but a weak positive association was seen with FM loss (r = 0.182, P = 0.01, n = 199) and a trend with weight loss (r = 0.128, P = 0.072, n = 199). ßHB was a significant predictor of both weight and FM loss (kg), after adjusting for age, sex, baseline BMI, and intervention study. CONCLUSIONS The magnitude of ketosis is not associated with FFM preservation. However, the higher the level of ketosis, the greater the weight and FM loss. Further studies are needed to confirm these findings and to explore the mechanisms involved. This trial was registered at clinicaltrials.gov identifier as NCT01834859, NCT04051190, NCT02944253.
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Affiliation(s)
- Catia Martins
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL, Unites States; Obesity Research Group, Department of Clinical and Molecular Medicine, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway; Centre for Obesity and Innovation (ObeCe), Clinic of Surgery, St. Olav University Hospital, Trondheim, Norway.
| | - Siren Nymo
- Obesity Research Group, Department of Clinical and Molecular Medicine, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway; Nord-Trøndelag Hospital Trust, Clinic of Surgery, Namsos Hospital, Namsos, Norway
| | - Marthe I Aukan
- Obesity Research Group, Department of Clinical and Molecular Medicine, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - Jessica A Roekenes
- Obesity Research Group, Department of Clinical and Molecular Medicine, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | | | - Gary R Hunter
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL, Unites States
| | - Barbara A Gower
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL, Unites States
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Competing paradigms of obesity pathogenesis: energy balance versus carbohydrate-insulin models. Eur J Clin Nutr 2022; 76:1209-1221. [PMID: 35896818 PMCID: PMC9436778 DOI: 10.1038/s41430-022-01179-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 06/24/2022] [Accepted: 06/28/2022] [Indexed: 02/07/2023]
Abstract
The obesity pandemic continues unabated despite a persistent public health campaign to decrease energy intake (“eat less”) and increase energy expenditure (“move more”). One explanation for this failure is that the current approach, based on the notion of energy balance, has not been adequately embraced by the public. Another possibility is that this approach rests on an erroneous paradigm. A new formulation of the energy balance model (EBM), like prior versions, considers overeating (energy intake > expenditure) the primary cause of obesity, incorporating an emphasis on “complex endocrine, metabolic, and nervous system signals” that control food intake below conscious level. This model attributes rising obesity prevalence to inexpensive, convenient, energy-dense, “ultra-processed” foods high in fat and sugar. An alternative view, the carbohydrate-insulin model (CIM), proposes that hormonal responses to highly processed carbohydrates shift energy partitioning toward deposition in adipose tissue, leaving fewer calories available for the body’s metabolic needs. Thus, increasing adiposity causes overeating to compensate for the sequestered calories. Here, we highlight robust contrasts in how the EBM and CIM view obesity pathophysiology and consider deficiencies in the EBM that impede paradigm testing and refinement. Rectifying these deficiencies should assume priority, as a constructive paradigm clash is needed to resolve long-standing scientific controversies and inform the design of new models to guide prevention and treatment. Nevertheless, public health action need not await resolution of this debate, as both models target processed carbohydrates as major drivers of obesity.
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Wong JMW, Yu S, Ma C, Mehta T, Dickinson SL, Allison DB, Heymsfield SB, Ebbeling CB, Ludwig DS. Stimulated Insulin Secretion Predicts Changes in Body Composition Following Weight Loss in Adults with High BMI. J Nutr 2022; 152:655-662. [PMID: 34587231 DOI: 10.1093/jn/nxab315] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 08/02/2021] [Accepted: 08/26/2021] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND The aim of obesity treatment is to promote loss of fat relative to lean mass. However, body composition changes with calorie restriction differ among individuals. OBJECTIVES The goal of this study was to test the hypothesis that insulin secretion predicts body composition changes among young and middle-age adults with high BMI (in kg/m2) following major weight loss. METHODS Exploratory analyses were conducted with pre-randomization data from 2 large feeding trials: the Framingham, Boston, Bloomington, Birmingham, and Baylor study (FB4; n = 82, 43.9% women, BMI ≥27) and the Framingham State Food Study [(FS)2; n = 161, 69.6% women, BMI ≥25]. Participants in the 2 trials consumed calorie-restricted moderate-carbohydrate or very-low-carbohydrate diets to produce 12-18% weight loss in ∼14 wk or 10-14% in ∼10 wk, respectively. We determined insulin concentration 30 min after a 75-g oral glucose load (insulin-30) as a measure of insulin secretion and HOMA-IR as a measure of insulin resistance at baseline. Body composition was determined by DXA at baseline and post-weight loss. Associations were analyzed using general linear models with adjustment for covariates. RESULTS In FB4, higher insulin-30 was associated with a smaller decrease in fat mass (0.441 kg per 100 μIU/mL increment in baseline insulin-30; P = 0.005; -1.20-kg mean difference between the first compared with the fifth group of insulin-30) and a larger decrease in lean mass (-0.465 kg per 100 μIU/mL; P = 0.004; 1.27-kg difference). Participants with higher insulin-30 lost a smaller proportion of weight loss as fat (-3.37% per 100 μIU/mL; P = 0.003; 9.20% difference). Greater HOMA-IR was also significantly associated with adverse body composition changes. Results from (FS)2 were qualitatively similar but of a smaller magnitude. CONCLUSIONS Baseline insulin dynamics predict substantial individual differences in body composition following weight loss. These findings may inform understanding of the pathophysiological basis for weight regain and the design of more effective obesity treatment. Registered at clinicaltrials.gov as NCT03394664 and NCT02068885.
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Affiliation(s)
- Julia M W Wong
- New Balance Foundation Obesity Prevention Center, Boston Children's Hospital, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA
| | - Shui Yu
- New Balance Foundation Obesity Prevention Center, Boston Children's Hospital, Boston, MA, USA
| | - Clement Ma
- Harvard Medical School, Boston, MA, USA.,Dana-Farber/Boston Children's Cancer and Blood Disorders Center, Boston, MA, USA
| | - Tapan Mehta
- Department of Health Services Administration, School of Health Professions, University of Alabama at Birmingham, Birmingham, AL, USA
| | | | - David B Allison
- Indiana University School of Public Health-Bloomington, Bloomington, IN, USA
| | - Steven B Heymsfield
- Metabolism & Body Composition Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA, USA
| | - Cara B Ebbeling
- New Balance Foundation Obesity Prevention Center, Boston Children's Hospital, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA
| | - David S Ludwig
- New Balance Foundation Obesity Prevention Center, Boston Children's Hospital, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA
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7
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Ludwig DS, Aronne LJ, Astrup A, de Cabo R, Cantley LC, Friedman MI, Heymsfield SB, Johnson JD, King JC, Krauss RM, Lieberman DE, Taubes G, Volek JS, Westman EC, Willett WC, Yancy WS, Ebbeling CB. The carbohydrate-insulin model: a physiological perspective on the obesity pandemic. Am J Clin Nutr 2021; 114:1873-1885. [PMID: 34515299 PMCID: PMC8634575 DOI: 10.1093/ajcn/nqab270] [Citation(s) in RCA: 122] [Impact Index Per Article: 40.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 07/26/2021] [Indexed: 12/29/2022] Open
Abstract
According to a commonly held view, the obesity pandemic is caused by overconsumption of modern, highly palatable, energy-dense processed foods, exacerbated by a sedentary lifestyle. However, obesity rates remain at historic highs, despite a persistent focus on eating less and moving more, as guided by the energy balance model (EBM). This public health failure may arise from a fundamental limitation of the EBM itself. Conceptualizing obesity as a disorder of energy balance restates a principle of physics without considering the biological mechanisms that promote weight gain. An alternative paradigm, the carbohydrate-insulin model (CIM), proposes a reversal of causal direction. According to the CIM, increasing fat deposition in the body-resulting from the hormonal responses to a high-glycemic-load diet-drives positive energy balance. The CIM provides a conceptual framework with testable hypotheses for how various modifiable factors influence energy balance and fat storage. Rigorous research is needed to compare the validity of these 2 models, which have substantially different implications for obesity management, and to generate new models that best encompass the evidence.
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Affiliation(s)
- David S Ludwig
- New Balance Foundation Obesity Prevention Center, Boston Children's Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
- Department of Nutrition, Harvard TH Chan School of Public Health, Boston, MA, USA
| | - Louis J Aronne
- Comprehensive Weight Control Center, Weill Cornell Medicine, New York, NY, USA
| | - Arne Astrup
- Department of Nutrition, Exercise, and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Rafael de Cabo
- Translational Gerontology Branch, National Institute on Aging, NIH, Baltimore, MD, USA
| | - Lewis C Cantley
- Department of Medicine, Weill Cornell Medicine, New York, NY, USA
| | - Mark I Friedman
- Monell Chemical Senses Center, Philadelphia, PA, USA
- Nutrition Science Initiative, San Diego, CA, USA
| | - Steven B Heymsfield
- Metabolism & Body Composition Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA, USA
| | - James D Johnson
- Diabetes Research Group, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
- Institute for Personalized Therapeutic Nutrition, Vancouver, British Columbia, Canada
| | - Janet C King
- Department of Nutritional Sciences & Toxicology, University of California Berkeley, Berkeley, CA, USA
| | - Ronald M Krauss
- Department of Pediatrics, University of California San Francisco, San Francisco, CA, USA
- Department of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Daniel E Lieberman
- Department of Human Evolutionary Biology, Harvard University, Cambridge, MA, USA
| | - Gary Taubes
- Nutrition Science Initiative, San Diego, CA, USA
| | - Jeff S Volek
- Department of Human Sciences, Ohio State University, Columbus, OH, USA
| | - Eric C Westman
- Department of Medicine, Duke University School of Medicine, Durham, NC, USA
| | - Walter C Willett
- Department of Nutrition, Harvard TH Chan School of Public Health, Boston, MA, USA
- Channing Division of Network Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | - William S Yancy
- Department of Medicine, Duke University School of Medicine, Durham, NC, USA
| | - Cara B Ebbeling
- New Balance Foundation Obesity Prevention Center, Boston Children's Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
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Alternative Dietary Patterns for Americans: Low-Carbohydrate Diets. Nutrients 2021; 13:nu13103299. [PMID: 34684300 PMCID: PMC8537012 DOI: 10.3390/nu13103299] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 09/04/2021] [Accepted: 09/09/2021] [Indexed: 12/11/2022] Open
Abstract
The decades-long dietary experiment embodied in the Dietary Guidelines for Americans (DGA) focused on limiting fat, especially saturated fat, and higher carbohydrate intake has coincided with rapidly escalating epidemics of obesity and type 2 diabetes (T2D) that are contributing to the progression of cardiovascular disease (CVD) and other diet-related chronic diseases. Moreover, the lack of flexibility in the DGA as it pertains to low carbohydrate approaches does not align with the contemporary trend toward precision nutrition. We argue that personalizing the level of dietary carbohydrate should be a high priority based on evidence that Americans have a wide spectrum of metabolic variability in their tolerance to high carbohydrate loads. Obesity, metabolic syndrome, and T2D are conditions strongly associated with insulin resistance, a condition exacerbated by increased dietary carbohydrate and improved by restricting carbohydrate. Low-carbohydrate diets are grounded across the time-span of human evolution, have well-established biochemical principles, and are now supported by multiple clinical trials in humans that demonstrate consistent improvements in multiple established risk factors associated with insulin resistance and cardiovascular disease. The American Diabetes Association (ADA) recently recognized a low carbohydrate eating pattern as an effective approach for patients with diabetes. Despite this evidence base, low-carbohydrate diets are not reflected in the DGA. As the DGA Dietary Patterns have not been demonstrated to be universally effective in addressing the needs of many Americans and recognizing the lack of widely available treatments for obesity, metabolic syndrome, and T2D that are safe, effective, and sustainable, the argument for an alternative, low-carbohydrate Dietary Pattern is all the more compelling.
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9
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Buga A, Kackley ML, Crabtree CD, Sapper TN, Mccabe L, Fell B, LaFountain RA, Hyde PN, Martini ER, Bowman J, Pan Y, Scandling D, Brownlow ML, O'Connor A, Simonetti OP, Kraemer WJ, Volek JS. The Effects of a 6-Week Controlled, Hypocaloric Ketogenic Diet, With and Without Exogenous Ketone Salts, on Body Composition Responses. Front Nutr 2021; 8:618520. [PMID: 33869263 PMCID: PMC8044842 DOI: 10.3389/fnut.2021.618520] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Accepted: 02/23/2021] [Indexed: 01/16/2023] Open
Abstract
Background: Ketogenic diets (KDs) that elevate beta-hydroxybutyrate (BHB) promote weight and fat loss. Exogenous ketones, such as ketone salts (KS), also elevate BHB concentrations with the potential to protect against muscle loss during caloric restriction. Whether augmenting ketosis with KS impacts body composition responses to a well-formulated KD remains unknown. Purpose: To explore the effects of energy-matched, hypocaloric KD feeding (<50 g carbohydrates/day; 1.5 g/kg/day protein), with and without the inclusion of KS, on weight loss and body composition responses. Methods: Overweight and obese adults were provided a precisely defined hypocaloric KD (~75% of energy expenditure) for 6 weeks. In a double-blind manner, subjects were randomly assigned to receive ~24 g/day of a racemic BHB-salt (KD + KS; n = 12) or placebo (KD + PL; n = 13). A matched comparison group (n = 12) was separately assigned to an isoenergetic/isonitrogenous low-fat diet (LFD). Body composition parameters were assessed by dual x-ray absorptiometry and magnetic resonance imaging. Results: The KD induced nutritional ketosis (>1.0 mM capillary BHB) throughout the study (p < 0.001), with higher fasting concentrations observed in KD + KS than KD + PL for the first 2 weeks (p < 0.05). There were decreases in body mass, whole body fat and lean mass, mid-thigh muscle cross-sectional area, and both visceral and subcutaneous adipose tissues (p < 0.001), but no group differences between the two KDs or with the LFD. Urine nitrogen excretion was significantly higher in KD + PL than LFD (p < 0.01) and trended higher in KD + PL compared to KD + KS (p = 0.076), whereas the nitrogen excretion during KD + KS was similar to LFD (p > 0.05). Conclusion: Energy-matched hypocaloric ketogenic diets favorably affected body composition but were not further impacted by administration of an exogenous BHB-salt that augmented ketosis. The trend for less nitrogen loss with the BHB-salt, if manifested over a longer period of time, may contribute to preserved lean mass.
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Affiliation(s)
- Alex Buga
- Department of Human Sciences, The Ohio State University, Columbus, OH, United States
| | - Madison L. Kackley
- Department of Human Sciences, The Ohio State University, Columbus, OH, United States
| | | | - Teryn N. Sapper
- Department of Human Sciences, The Ohio State University, Columbus, OH, United States
| | - Lauren Mccabe
- Department of Human Sciences, The Ohio State University, Columbus, OH, United States
| | - Brandon Fell
- Department of Human Sciences, The Ohio State University, Columbus, OH, United States
| | - Rich A. LaFountain
- Department of Human Sciences, The Ohio State University, Columbus, OH, United States
| | - Parker N. Hyde
- Department of Human Sciences, The Ohio State University, Columbus, OH, United States
| | - Emily R. Martini
- Department of Human Sciences, The Ohio State University, Columbus, OH, United States
| | - Jessica Bowman
- Department of Human Sciences, The Ohio State University, Columbus, OH, United States
| | - Yue Pan
- Department of Radiology, Davis Heart & Lung Research Institute, The Ohio State University, Columbus, OH, United States
- Division of Cardiovascular Medicine, Department of Internal Medicine, The Ohio State University, Columbus, OH, United States
- Department of Radiology, Wexner Medical Center, The Ohio State University, Columbus, OH, United States
| | - Debbie Scandling
- Department of Radiology, Davis Heart & Lung Research Institute, The Ohio State University, Columbus, OH, United States
- Division of Cardiovascular Medicine, Department of Internal Medicine, The Ohio State University, Columbus, OH, United States
- Department of Radiology, Wexner Medical Center, The Ohio State University, Columbus, OH, United States
| | - Milene L. Brownlow
- Research and Development Department, Metagenics, Inc., Aliso Viejo, CA, United States
| | - Annalouise O'Connor
- Research and Development Department, Metagenics, Inc., Aliso Viejo, CA, United States
| | - Orlando P. Simonetti
- Department of Radiology, Davis Heart & Lung Research Institute, The Ohio State University, Columbus, OH, United States
- Division of Cardiovascular Medicine, Department of Internal Medicine, The Ohio State University, Columbus, OH, United States
- Department of Radiology, Wexner Medical Center, The Ohio State University, Columbus, OH, United States
| | - William J. Kraemer
- Department of Human Sciences, The Ohio State University, Columbus, OH, United States
| | - Jeff S. Volek
- Department of Human Sciences, The Ohio State University, Columbus, OH, United States
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10
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Ludwig DS, Dickinson SL, Henschel B, Ebbeling CB, Allison DB. Do Lower-Carbohydrate Diets Increase Total Energy Expenditure? An Updated and Reanalyzed Meta-Analysis of 29 Controlled-Feeding Studies. J Nutr 2020; 151:482-490. [PMID: 33274750 PMCID: PMC7948201 DOI: 10.1093/jn/nxaa350] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 09/29/2020] [Accepted: 10/12/2020] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND The effect of macronutrient composition on total energy expenditure (TEE) remains controversial, with divergent findings among studies. One source of heterogeneity may be study duration, as physiological adaptation to lower carbohydrate intake may require 2 to 3 wk. OBJECTIVE We tested the hypothesis that the effects of carbohydrate [expressed as % of energy intake (EI)] on TEE vary with time. METHODS The sample included trials from a previous meta-analysis and new trials identified in a PubMed search through 9 March 2020 comparing lower- and higher-carbohydrate diets, controlled for EI or body weight. Three reviewers independently extracted data and reconciled discrepancies. Effects on TEE were pooled using inverse-variance-weighted meta-analysis, with between-study heterogeneity assessed using the I2 statistic. Meta-regression was used to quantify the influence of study duration, dichotomized at 2.5 wk. RESULTS The 29 trials ranged in duration from 1 to 140 d (median: 4 d) and included 617 participants. Difference in carbohydrate between intervention arms ranged from 8% to 77% EI (median: 30%). Compared with reported findings in the prior analysis (I2 = 32.2%), we found greater heterogeneity (I2 = 90.9% in the reanalysis, 81.6% in the updated analysis). Study duration modified the diet effect on TEE (P < 0.001). Among 23 shorter trials, TEE was reduced on lower-carbohydrate diets (-50.0 kcal/d; 95% CI: -77.4, -22.6 kcal/d) with substantial heterogeneity (I2 = 69.8). Among 6 longer trials, TEE was increased on low-carbohydrate diets (135.4 kcal/d; 95% CI: 72.0, 198.7 kcal/d) with low heterogeneity (I2 = 26.4). Expressed per 10% decrease in carbohydrate as %EI, the TEE effects in shorter and longer trials were -14.5 kcal/d and 50.4 kcal/d, respectively. Findings were materially unchanged in sensitivity analyses. CONCLUSIONS Lower-carbohydrate diets transiently reduce TEE, with a larger increase after ∼2.5 wk. These findings highlight the importance of longer trials to understand chronic macronutrient effects and suggest a mechanism whereby lower-carbohydrate diets may facilitate weight loss.
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Affiliation(s)
| | | | - Beate Henschel
- Indiana University School of Public Health–Bloomington, Bloomington, IN, USA
| | - Cara B Ebbeling
- New Balance Foundation Obesity Prevention Center, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA
| | - David B Allison
- Indiana University School of Public Health–Bloomington, Bloomington, IN, USA
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11
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Maston G, Franklin J, Gibson AA, Manson E, Hocking S, Sainsbury A, Markovic TP. Attitudes and Approaches to Use of Meal Replacement Products among Healthcare Professionals in Management of Excess Weight. Behav Sci (Basel) 2020; 10:E136. [PMID: 32906702 PMCID: PMC7551264 DOI: 10.3390/bs10090136] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 09/03/2020] [Accepted: 09/03/2020] [Indexed: 01/01/2023] Open
Abstract
Meal replacement product-based diets are an effective weight loss intervention used in the management of obesity. Historically, these diets have been underutilised by HealthCare Professionals (HCPs). An online survey of mixed methods design was distributed to HCPs to capture current perceptions and prescribing patterns of meal replacement products (MRPs) in the management of overweight and obesity. A total of 303 HCPs working in weight management across Australia began the survey and 197 (65%) completed it. While over 70% of HCPs have prescribed MRP currently or in the past, MRPs are only prescribed to a median 7% of patients seeking weight management treatment. Qualitative analysis identified potential barriers to MRP prescription, which include experience with patient non-compliance, perceived poor long-term weight loss durability and safety concerns regarding the product and its use as a total meal replacement program. Safety concerns are centred on the perceived risk of weight cycling and its potential negative psychological impact. MRP prescription is 66% more likely to occur if HCPs had formal training in the use of MRPs relative to those who did not, with a relative risk (RR) of 1.7 (95% CI 1.4, 2.0). This study highlights the potential barriers to the prescription of MRPs, which are centred around safety concerns. This also indicates that formal training may enhance the likelihood of prescribing MRPs, suggesting that once HCPs have a comprehensive understanding of the products and the evidence behind their use, their prescription is likely to be increased.
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Affiliation(s)
- Gabrielle Maston
- Faculty of Medicine and Health, The University of Sydney, The Boden Collaboration for Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, Camperdown, NSW 2050, Australia; (S.H.); (T.P.M.)
- Metabolism & Obesity Services, Royal Prince Alfred Hospital, Camperdown, NSW 2050, Australia; (J.F.); (E.M.)
| | - Janet Franklin
- Metabolism & Obesity Services, Royal Prince Alfred Hospital, Camperdown, NSW 2050, Australia; (J.F.); (E.M.)
| | - Alice A. Gibson
- School of Public Health, Faculty of Medicine and Health, Centre for Health Policy, The University of Sydney, NSW 2050, Australia;
| | - Elisa Manson
- Metabolism & Obesity Services, Royal Prince Alfred Hospital, Camperdown, NSW 2050, Australia; (J.F.); (E.M.)
| | - Samantha Hocking
- Faculty of Medicine and Health, The University of Sydney, The Boden Collaboration for Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, Camperdown, NSW 2050, Australia; (S.H.); (T.P.M.)
- Metabolism & Obesity Services, Royal Prince Alfred Hospital, Camperdown, NSW 2050, Australia; (J.F.); (E.M.)
| | - Amanda Sainsbury
- Faculty of Science, School of Human Sciences, The University of Western Australia, Crawley, WA 6009, Australia;
| | - Tania P. Markovic
- Faculty of Medicine and Health, The University of Sydney, The Boden Collaboration for Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, Camperdown, NSW 2050, Australia; (S.H.); (T.P.M.)
- Metabolism & Obesity Services, Royal Prince Alfred Hospital, Camperdown, NSW 2050, Australia; (J.F.); (E.M.)
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12
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Dietary acid-base load and its association with risk of osteoporotic fractures and low estimated skeletal muscle mass. Eur J Clin Nutr 2020; 74:33-42. [PMID: 32873955 DOI: 10.1038/s41430-020-0686-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
BACKGROUND/OBJECTIVES Age-related decline in skeletal muscle mass and strength, loss of bone density, and increased risk of osteoporotic fractures are important public health issues. Systemic acid-base balance is affected by dietary intake and may be relevant to these conditions. We therefore investigated associations of dietary acid-base load with skeletal muscle mass, bone density status, and fracture risk. SUBJECTS/METHODS We analysed the European Prospective Investigation into Cancer and Nutrition-Norfolk cohort of >25,000 individuals, 39-79 years at baseline. Potential renal acid load (PRAL) was calculated from 7-day food diary data. As a proxy for skeletal muscle mass, we estimated fat-free mass from bioelectrical impedance analysis and scaled this for BMI (FFMBMI). Bone density status was assessed by heel-bone broadband ultrasound attenuation (BUA), and fracture rates were obtained from health-care records. Multivariable regression was used to test musculoskeletal outcomes across sex-specific quintiles of PRAL. RESULTS PRAL in quintiles was negatively associated with FFMBMI in men (n = 6350, p < 0.001) and women (n = 7989, p < 0.001), with quintile 5 vs 1 differences of -1.5% and -3.2% (both p < 0.001). PRAL was also negatively associated with BUA in women (n = 8312, p = 0.016; quintile 5 vs 1 difference -1.5%, p = 0.024). The combined hazard of hip, wrist and spine fractures (mean ± SD follow-up 17.9 ± 4.9 years) was higher with increasing quintiles of PRAL in men (610 fractures; n = 11,511; p = 0.013) and women (1583 fractures; n = 13,927; p = 0.009), with quintile 5 vs 1 hazard ratios of 1.33 (95% CI: 1.03-1.72, p = 0.029) and 1.21 (95% CI: 1.03-1.42, p = 0.022), but associations were not consistent for all fractures sites and age groups tested. CONCLUSIONS This study provides strong evidence, albeit observational, for a negative association between PRAL and musculoskeletal health in middle to older age men and women, and thus supports the rationale for a less acidic dietary load.
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13
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Maston G, Gibson AA, Kahlaee HR, Franklin J, Manson E, Sainsbury A, Markovic TP. Effectiveness and Characterization of Severely Energy-Restricted Diets in People with Class III Obesity: Systematic Review and Meta-Analysis. Behav Sci (Basel) 2019; 9:E144. [PMID: 31817943 PMCID: PMC6960910 DOI: 10.3390/bs9120144] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2019] [Revised: 11/24/2019] [Accepted: 12/03/2019] [Indexed: 12/17/2022] Open
Abstract
Severely energy-restricted diets are used in obesity management, but their efficacy in people with class III obesity (body mass index ≥40 kg/m2) is uncertain. The aims of this systematic review and meta-analysis were to determine the effectiveness and characteristics of severely energy-restricted diets in people with class III obesity. As there was a lack of publications reporting long-term dietary interventions and randomised controlled trial designs, our original publication inclusion criteria were broadened to include uncontrolled study designs and a higher upper limit of energy intake. Eligible publications reported studies including adults with class III obesity and that assessed a diet with daily energy intake ≤5000 kJ for ≥4 weeks. Among 572 unique publications from 4 databases, 11 were eligible and 10 were suitable for meta-analysis. Our original intention was to classify comparison arms into short-term (<6 months) and long-term (>1 year) interventions. Due to the lack of long-term data found, comparison arms were classified according to the commonalities in dietary intervention length among the included publications, namely dietary interventions of 4 weeks' duration and those of ≥6 weeks' duration. After a 4-week severely energy-restricted diet intervention, the pooled average weight loss was 9.81 (95% confidence interval 10.80, 8.83) kg, with a 95% prediction interval of 6.38 to 13.25 kg, representing a loss of approximately 4.1 to 8.6% of initial body weight. Diets ≥6 weeks' duration produced 25.78 (29.42, 22.15) kg pooled average weight loss, with a 95% prediction interval of 13.77 to 37.80 kg, representing approximately 10.2 to 28.0% weight loss. Daily dietary prescriptions ranged from 330 to 5000 kJ (mean ± standard deviation 2260 ± 1400 kJ), and had wide variations in macronutrient composition. The diets were administered mostly via liquid meal replacement products. While the included publications had a moderate risk of bias score, which may inflate reported weight loss outcomes, the published data to date suggest that severely energy-restricted diets, delivered via diets of varying composition, effectively produce clinically relevant weight loss (≥10% of initial body weight) when used for 6 weeks or more in people with class III obesity.
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Affiliation(s)
- Gabrielle Maston
- The Boden Collaboration for Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, Faculty of Medicine and Health, The University of Sydney, Sydney 2006, Australia; (A.A.G.); (A.S.); (T.P.M.)
- Metabolism & Obesity Services, Royal Prince Alfred Hospital, Sydney 2006, Australia; (J.F.); (E.M.)
| | - Alice A. Gibson
- The Boden Collaboration for Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, Faculty of Medicine and Health, The University of Sydney, Sydney 2006, Australia; (A.A.G.); (A.S.); (T.P.M.)
| | - H. Reza Kahlaee
- Faculty of Medicine and Health, School of Pharmacy, The University of Sydney, Sydney 2006, Australia;
- School of Life, and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney 2006, Australia
| | - Janet Franklin
- Metabolism & Obesity Services, Royal Prince Alfred Hospital, Sydney 2006, Australia; (J.F.); (E.M.)
| | - Elisa Manson
- Metabolism & Obesity Services, Royal Prince Alfred Hospital, Sydney 2006, Australia; (J.F.); (E.M.)
| | - Amanda Sainsbury
- The Boden Collaboration for Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, Faculty of Medicine and Health, The University of Sydney, Sydney 2006, Australia; (A.A.G.); (A.S.); (T.P.M.)
| | - Tania P. Markovic
- The Boden Collaboration for Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, Faculty of Medicine and Health, The University of Sydney, Sydney 2006, Australia; (A.A.G.); (A.S.); (T.P.M.)
- Metabolism & Obesity Services, Royal Prince Alfred Hospital, Sydney 2006, Australia; (J.F.); (E.M.)
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14
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Astley CM, Todd JN, Salem RM, Vedantam S, Ebbeling CB, Huang PL, Ludwig DS, Hirschhorn JN, Florez JC. Genetic Evidence That Carbohydrate-Stimulated Insulin Secretion Leads to Obesity. Clin Chem 2019; 64:192-200. [PMID: 29295838 DOI: 10.1373/clinchem.2017.280727] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 10/17/2017] [Indexed: 12/22/2022]
Abstract
BACKGROUND A fundamental precept of the carbohydrate-insulin model of obesity is that insulin secretion drives weight gain. However, fasting hyperinsulinemia can also be driven by obesity-induced insulin resistance. We used genetic variation to isolate and estimate the potentially causal effect of insulin secretion on body weight. METHODS Genetic instruments of variation of insulin secretion [assessed as insulin concentration 30 min after oral glucose (insulin-30)] were used to estimate the causal relationship between increased insulin secretion and body mass index (BMI), using bidirectional Mendelian randomization analysis of genome-wide association studies. Data sources included summary results from the largest published metaanalyses of predominantly European ancestry for insulin secretion (n = 26037) and BMI (n = 322154), as well as individual-level data from the UK Biobank (n = 138541). Data from the Cardiology and Metabolic Patient Cohort study at Massachusetts General Hospital (n = 1675) were used to validate genetic associations with insulin secretion and to test the observational association of insulin secretion and BMI. RESULTS Higher genetically determined insulin-30 was strongly associated with higher BMI (β = 0.098, P = 2.2 × 10-21), consistent with a causal role in obesity. Similar positive associations were noted in sensitivity analyses using other genetic variants as instrumental variables. By contrast, higher genetically determined BMI was not associated with insulin-30. CONCLUSIONS Mendelian randomization analyses provide evidence for a causal relationship of glucose-stimulated insulin secretion on body weight, consistent with the carbohydrate-insulin model of obesity.
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Affiliation(s)
- Christina M Astley
- Department of Medicine, Division of Endocrinology, Boston Children's Hospital, Boston, MA.,Departments of Medicine and Pediatrics, Harvard Medical School, Boston, MA.,Programs in Metabolism and Medical & Population Genetics, Broad Institute, Cambridge, MA
| | - Jennifer N Todd
- Department of Medicine, Division of Endocrinology, Boston Children's Hospital, Boston, MA.,Departments of Medicine and Pediatrics, Harvard Medical School, Boston, MA.,Programs in Metabolism and Medical & Population Genetics, Broad Institute, Cambridge, MA.,Diabetes Unit and Center for Genomic Medicine, Department of Medicine, Massachusetts General Hospital, Boston, MA
| | - Rany M Salem
- Department of Family Medicine and Public Health, University of California, San Diego, CA
| | - Sailaja Vedantam
- Department of Medicine, Division of Endocrinology, Boston Children's Hospital, Boston, MA.,Departments of Medicine and Pediatrics, Harvard Medical School, Boston, MA
| | - Cara B Ebbeling
- Department of Medicine, Division of Endocrinology, Boston Children's Hospital, Boston, MA.,Departments of Medicine and Pediatrics, Harvard Medical School, Boston, MA
| | - Paul L Huang
- Departments of Medicine and Pediatrics, Harvard Medical School, Boston, MA.,Cardiology Division, Department of Medicine, Massachusetts General Hospital, Boston, MA
| | - David S Ludwig
- Department of Medicine, Division of Endocrinology, Boston Children's Hospital, Boston, MA; .,Departments of Medicine and Pediatrics, Harvard Medical School, Boston, MA
| | - Joel N Hirschhorn
- Department of Medicine, Division of Endocrinology, Boston Children's Hospital, Boston, MA; .,Departments of Medicine and Pediatrics, Harvard Medical School, Boston, MA.,Programs in Metabolism and Medical & Population Genetics, Broad Institute, Cambridge, MA
| | - Jose C Florez
- Departments of Medicine and Pediatrics, Harvard Medical School, Boston, MA; .,Programs in Metabolism and Medical & Population Genetics, Broad Institute, Cambridge, MA.,Diabetes Unit and Center for Genomic Medicine, Department of Medicine, Massachusetts General Hospital, Boston, MA
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15
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Ebbeling CB, Feldman HA, Klein GL, Wong JMW, Bielak L, Steltz SK, Luoto PK, Wolfe RR, Wong WW, Ludwig DS. Effects of a low carbohydrate diet on energy expenditure during weight loss maintenance: randomized trial. BMJ 2018; 363:k4583. [PMID: 30429127 PMCID: PMC6233655 DOI: 10.1136/bmj.k4583] [Citation(s) in RCA: 156] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/24/2018] [Indexed: 12/13/2022]
Abstract
OBJECTIVE To determine the effects of diets varying in carbohydrate to fat ratio on total energy expenditure. DESIGN Randomized trial. SETTING Multicenter collaboration at US two sites, August 2014 to May 2017. PARTICIPANTS 164 adults aged 18-65 years with a body mass index of 25 or more. INTERVENTIONS After 12% (within 2%) weight loss on a run-in diet, participants were randomly assigned to one of three test diets according to carbohydrate content (high, 60%, n=54; moderate, 40%, n=53; or low, 20%, n=57) for 20 weeks. Test diets were controlled for protein and were energy adjusted to maintain weight loss within 2 kg. To test for effect modification predicted by the carbohydrate-insulin model, the sample was divided into thirds of pre-weight loss insulin secretion (insulin concentration 30 minutes after oral glucose). MAIN OUTCOME MEASURES The primary outcome was total energy expenditure, measured with doubly labeled water, by intention-to-treat analysis. Per protocol analysis included participants who maintained target weight loss, potentially providing a more precise effect estimate. Secondary outcomes were resting energy expenditure, measures of physical activity, and levels of the metabolic hormones leptin and ghrelin. RESULTS Total energy expenditure differed by diet in the intention-to-treat analysis (n=162, P=0.002), with a linear trend of 52 kcal/d (95% confidence interval 23 to 82) for every 10% decrease in the contribution of carbohydrate to total energy intake (1 kcal=4.18 kJ=0.00418 MJ). Change in total energy expenditure was 91 kcal/d (95% confidence interval -29 to 210) greater in participants assigned to the moderate carbohydrate diet and 209 kcal/d (91 to 326) greater in those assigned to the low carbohydrate diet compared with the high carbohydrate diet. In the per protocol analysis (n=120, P<0.001), the respective differences were 131 kcal/d (-6 to 267) and 278 kcal/d (144 to 411). Among participants in the highest third of pre-weight loss insulin secretion, the difference between the low and high carbohydrate diet was 308 kcal/d in the intention-to-treat analysis and 478 kcal/d in the per protocol analysis (P<0.004). Ghrelin was significantly lower in participants assigned to the low carbohydrate diet compared with those assigned to the high carbohydrate diet (both analyses). Leptin was also significantly lower in participants assigned to the low carbohydrate diet (per protocol). CONCLUSIONS Consistent with the carbohydrate-insulin model, lowering dietary carbohydrate increased energy expenditure during weight loss maintenance. This metabolic effect may improve the success of obesity treatment, especially among those with high insulin secretion. TRIAL REGISTRATION ClinicalTrials.gov NCT02068885.
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Affiliation(s)
- Cara B Ebbeling
- New Balance Foundation Obesity Prevention Center, Division of Endocrinology, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA
- Harvard Medical School, Boston, MA, USA
| | - Henry A Feldman
- Harvard Medical School, Boston, MA, USA
- Institutional Centers for Clinical and Translational Research, Boston Children's Hospital, Boston, MA, USA
| | - Gloria L Klein
- New Balance Foundation Obesity Prevention Center, Division of Endocrinology, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Julia M W Wong
- New Balance Foundation Obesity Prevention Center, Division of Endocrinology, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA
- Harvard Medical School, Boston, MA, USA
| | - Lisa Bielak
- New Balance Foundation Obesity Prevention Center, Division of Endocrinology, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Sarah K Steltz
- New Balance Foundation Obesity Prevention Center, Division of Endocrinology, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Patricia K Luoto
- Department of Food and Nutrition, Framingham State University, Framingham, MA, USA
| | - Robert R Wolfe
- University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - William W Wong
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | - David S Ludwig
- New Balance Foundation Obesity Prevention Center, Division of Endocrinology, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA
- Harvard Medical School, Boston, MA, USA
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16
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Abstract
Despite intensive research, the causes of the obesity epidemic remain incompletely understood and conventional calorie-restricted diets continue to lack long-term efficacy. According to the carbohydrate-insulin model (CIM) of obesity, recent increases in the consumption of processed, high-glycemic-load carbohydrates produce hormonal changes that promote calorie deposition in adipose tissue, exacerbate hunger, and lower energy expenditure. Basic and genetic research provides mechanistic evidence in support of the CIM. In animals, dietary composition has been clearly demonstrated to affect metabolism and body composition, independently of calorie intake, consistent with CIM predictions. Meta-analyses of behavioral trials report greater weight loss with reduced-glycemic load vs low-fat diets, though these studies characteristically suffer from poor long-term compliance. Feeding studies have lacked the rigor and duration to test the CIM, but the longest such studies tend to show metabolic advantages for low-glycemic load vs low-fat diets. Beyond the type and amount of carbohydrate consumed, the CIM provides a conceptual framework for understanding how many dietary and nondietary exposures might alter hormones, metabolism, and adipocyte biology in ways that could predispose to obesity. Pending definitive studies, the principles of a low-glycemic load diet offer a practical alternative to the conventional focus on dietary fat and calorie restriction.
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Affiliation(s)
- David S Ludwig
- The New Balance Foundation Obesity Prevention Center, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Cara B Ebbeling
- The New Balance Foundation Obesity Prevention Center, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts
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17
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Thom G, Lean M. Is There an Optimal Diet for Weight Management and Metabolic Health? Gastroenterology 2017; 152:1739-1751. [PMID: 28214525 DOI: 10.1053/j.gastro.2017.01.056] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 01/10/2017] [Accepted: 01/17/2017] [Indexed: 12/24/2022]
Abstract
Individuals can lose body weight and improve health status on a wide range of energy (calorie)-restricted dietary interventions. In this paper, we have reviewed the effectiveness of the most commonly utilized diets, including low-fat, low-carbohydrate, and Mediterranean approaches, in addition to commercial slimming programs, meal replacements, and newly popularized intermittent fasting diets. We also consider the role of artificial sweeteners in weight management. Low-fat diets tend to improve low-density lipoprotein cholesterol the most, while lower-carbohydrate diets may preferentially improve triglycerides and high-density lipoprotein cholesterol. However, differences between diets are marginal. Weight loss improves almost all obesity-related co-morbidities and metabolic markers, regardless of the macronutrient composition of the diet, but individuals do vary in preferences and ability to adhere to different diets. Optimizing adherence is the most important factor for weight loss success, and this is enhanced by regular professional contact and supportive behavioral change programs. Maintaining weight losses in the long term remains the biggest challenge, and is undermined by an "obesogenic" environment and biological adaptations that accompany weight loss.
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Affiliation(s)
- George Thom
- University of Glasgow, Human Nutrition, School of Medicine, Dentistry & Nursing, Glasgow, Scotland, United Kingdom
| | - Mike Lean
- University of Glasgow, Human Nutrition, School of Medicine, Dentistry & Nursing, Glasgow, Scotland, United Kingdom.
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18
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Affiliation(s)
- David S Ludwig
- From the New Balance Foundation Obesity Prevention Center, Boston Children's Hospital, Boston, MA (DSL, e-mail: ; CBE)
| | - Cara B Ebbeling
- From the New Balance Foundation Obesity Prevention Center, Boston Children's Hospital, Boston, MA (DSL, e-mail: ; CBE)
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19
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Hall KD, Bemis T, Brychta R, Chen KY, Courville A, Crayner EJ, Goodwin S, Guo J, Howard L, Knuth ND, Miller BV, Prado CM, Siervo M, Skarulis MC, Walter M, Walter PJ, Yannai L. Calorie for Calorie, Dietary Fat Restriction Results in More Body Fat Loss than Carbohydrate Restriction in People with Obesity. Cell Metab 2015; 22:427-36. [PMID: 26278052 PMCID: PMC4603544 DOI: 10.1016/j.cmet.2015.07.021] [Citation(s) in RCA: 175] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 07/06/2015] [Accepted: 07/23/2015] [Indexed: 10/23/2022]
Abstract
Dietary carbohydrate restriction has been purported to cause endocrine adaptations that promote body fat loss more than dietary fat restriction. We selectively restricted dietary carbohydrate versus fat for 6 days following a 5-day baseline diet in 19 adults with obesity confined to a metabolic ward where they exercised daily. Subjects received both isocaloric diets in random order during each of two inpatient stays. Body fat loss was calculated as the difference between daily fat intake and net fat oxidation measured while residing in a metabolic chamber. Whereas carbohydrate restriction led to sustained increases in fat oxidation and loss of 53 ± 6 g/day of body fat, fat oxidation was unchanged by fat restriction, leading to 89 ± 6 g/day of fat loss, and was significantly greater than carbohydrate restriction (p = 0.002). Mathematical model simulations agreed with these data, but predicted that the body acts to minimize body fat differences with prolonged isocaloric diets varying in carbohydrate and fat.
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Affiliation(s)
- Kevin D Hall
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Thomas Bemis
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Robert Brychta
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kong Y Chen
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Amber Courville
- Clinical Center Nutrition Department, National Institutes of Health, Bethesda, MD 20892, USA
| | - Emma J Crayner
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Stephanie Goodwin
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Juen Guo
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Lilian Howard
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | | | - Bernard V Miller
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | | | - Mario Siervo
- Newcastle University, Newcastle upon Tyne NE4 5PL, UK
| | - Monica C Skarulis
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Mary Walter
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Peter J Walter
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Laura Yannai
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
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20
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Tischner C, Hofer A, Wulff V, Stepek J, Dumitru I, Becker L, Haack T, Kremer L, Datta AN, Sperl W, Floss T, Wurst W, Chrzanowska-Lightowlers Z, De Angelis MH, Klopstock T, Prokisch H, Wenz T. MTO1 mediates tissue specificity of OXPHOS defects via tRNA modification and translation optimization, which can be bypassed by dietary intervention. Hum Mol Genet 2015; 24:2247-66. [PMID: 25552653 PMCID: PMC4380071 DOI: 10.1093/hmg/ddu743] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Revised: 12/12/2014] [Accepted: 12/22/2014] [Indexed: 11/15/2022] Open
Abstract
Mitochondrial diseases often exhibit tissue-specific pathologies, but this phenomenon is poorly understood. Here we present regulation of mitochondrial translation by the Mitochondrial Translation Optimization Factor 1, MTO1, as a novel player in this scenario. We demonstrate that MTO1 mediates tRNA modification and controls mitochondrial translation rate in a highly tissue-specific manner associated with tissue-specific OXPHOS defects. Activation of mitochondrial proteases, aberrant translation products, as well as defects in OXPHOS complex assembly observed in MTO1 deficient mice further imply that MTO1 impacts translation fidelity. In our mouse model, MTO1-related OXPHOS deficiency can be bypassed by feeding a ketogenic diet. This therapeutic intervention is independent of the MTO1-mediated tRNA modification and involves balancing of mitochondrial and cellular secondary stress responses. Our results thereby establish mammalian MTO1 as a novel factor in the tissue-specific regulation of OXPHOS and fine tuning of mitochondrial translation accuracy.
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Affiliation(s)
- Christin Tischner
- Institute for Genetics and Cluster of Excellence: Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Zülpicher Str. 47A, Cologne 50674, Germany
| | - Annette Hofer
- Institute for Genetics and Cluster of Excellence: Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Zülpicher Str. 47A, Cologne 50674, Germany
| | - Veronika Wulff
- Institute for Genetics and Cluster of Excellence: Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Zülpicher Str. 47A, Cologne 50674, Germany
| | - Joanna Stepek
- Institute for Genetics and Cluster of Excellence: Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Zülpicher Str. 47A, Cologne 50674, Germany
| | - Iulia Dumitru
- Institute for Genetics and Cluster of Excellence: Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Zülpicher Str. 47A, Cologne 50674, Germany
| | - Lore Becker
- Department of Neurology, Friedrich-Baur-Institute, Ludwig-Maximilians-University, Munich 80336, Germany, German Mouse Clinic, Institute of Experimental Genetics
| | - Tobias Haack
- Institute of Human Genetics, German Network for Mitochondrial Disorders (mitoNET), Germany
| | - Laura Kremer
- Institute of Human Genetics, German Network for Mitochondrial Disorders (mitoNET), Germany
| | - Alexandre N Datta
- Division of Neuropediatrics and Developmental Medicine, University Children's Hospital Basel (UKBB), University of Basel, Basel 4031, Switzerland
| | - Wolfgang Sperl
- German Network for Mitochondrial Disorders (mitoNET), Germany, Department of Pediatrics, Paracelsus Medical University Salzburg, Salzburg, Austria
| | - Thomas Floss
- Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environment and Health (GmbH), Neuherberg 85764, Germany
| | - Wolfgang Wurst
- Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environment and Health (GmbH), Neuherberg 85764, Germany, Technical University Munich, Helmholtz Zentrum München, Neuherberg 85764, Germany, DZNE-German Center for Neurodegenerative Diseases, Munich, Germany, Max Planck Institute of Psychiatry, Munich 80804, Germany, German Center for Vertigo and Balance Disorders, Munich, Germany
| | - Zofia Chrzanowska-Lightowlers
- The Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, The Medical School, Newcastle upon Tyne NE2 4HH, UK
| | - Martin Hrabe De Angelis
- German Mouse Clinic, Institute of Experimental Genetics, German Center for Vertigo and Balance Disorders, Munich, Germany, Center of Life and Food Sciences Weihenstephan, Technische Universitat München, Freising 85350, Germany, German Center for Diabetes Research (DZD), Neuherberg 85764, Germany and Technische Universität München, Freising-Weihenstephan 85354, Germany
| | - Thomas Klopstock
- Department of Neurology, Friedrich-Baur-Institute, Ludwig-Maximilians-University, Munich 80336, Germany, German Mouse Clinic, Institute of Experimental Genetics, German Network for Mitochondrial Disorders (mitoNET), Germany, DZNE-German Center for Neurodegenerative Diseases, Munich, Germany, German Center for Vertigo and Balance Disorders, Munich, Germany
| | - Holger Prokisch
- Institute of Human Genetics, Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environment and Health (GmbH), Neuherberg 85764, Germany
| | - Tina Wenz
- Institute for Genetics and Cluster of Excellence: Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Zülpicher Str. 47A, Cologne 50674, Germany, German Network for Mitochondrial Disorders (mitoNET), Germany,
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21
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Scientific Opinion on the essential composition of total diet replacements for weight control. EFSA J 2015. [DOI: 10.2903/j.efsa.2015.3957] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Terzikhan N, Doets E, Vonk Noordegraaf‐Schouten M. Extensive literature search and review as preparatory work for the evaluation of the essential composition of total diet replacement products for weight control. ACTA ACUST UNITED AC 2015. [DOI: 10.2903/sp.efsa.2015.en-590] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- N. Terzikhan
- Pallas health research and consultancy the Netherlands
| | - E.L. Doets
- Pallas health research and consultancy the Netherlands
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23
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Mithal A, Bonjour JP, Boonen S, Burckhardt P, Degens H, El Hajj Fuleihan G, Josse R, Lips P, Morales Torres J, Rizzoli R, Yoshimura N, Wahl DA, Cooper C, Dawson-Hughes B. Impact of nutrition on muscle mass, strength, and performance in older adults. Osteoporos Int 2013; 24:1555-66. [PMID: 23247327 DOI: 10.1007/s00198-012-2236-y] [Citation(s) in RCA: 191] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Accepted: 09/20/2012] [Indexed: 12/25/2022]
Abstract
Muscle strength plays an important role in determining risk for falls, which result in fractures and other injuries. While bone loss has long been recognized as an inevitable consequence of aging, sarcopenia-the gradual loss of skeletal muscle mass and strength that occurs with advancing age-has recently received increased attention. A review of the literature was undertaken to identify nutritional factors that contribute to loss of muscle mass. The role of protein, acid-base balance, vitamin D/calcium, and other minor nutrients like B vitamins was reviewed. Muscle wasting is a multifactorial process involving intrinsic and extrinsic alterations. A loss of fast twitch fibers, glycation of proteins, and insulin resistance may play an important role in the loss of muscle strength and development of sarcopenia. Protein intake plays an integral part in muscle health and an intake of 1.0-1.2 g/kg of body weight per day is probably optimal for older adults. There is a moderate [corrected] relationship between vitamin D status and muscle strength. Chronic ingestion of acid-producing diets appears to have a negative impact on muscle performance, and decreases in vitamin B12 and folic acid intake may also impair muscle function through their action on homocysteine. An adequate nutritional intake and an optimal dietary acid-base balance are important elements of any strategy to preserve muscle mass and strength during aging.
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Affiliation(s)
- A Mithal
- Medanta Medicity, Sector 38, Gurgaon, India.
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Abstract
Mathematical modeling of human energy regulation and body weight change has recently reached the level of sophistication required for accurate predictions. Mathematical models are beginning to provide a quantitative framework for integrating experimental data in humans and thereby help us better understand the dynamic imbalances of energy and macronutrients that give rise to changes in body weight and composition. This review provides an overview of the various approaches that have been used to model body weight dynamics and energy regulation in humans, highlights several insights that these models have provided, and suggests how mathematical models can serve as a guide for future experimental research.
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Affiliation(s)
- Kevin D Hall
- Laboratory of Biological Modeling, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.
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Hall KD, Sacks G, Chandramohan D, Chow CC, Wang YC, Gortmaker SL, Swinburn BA. Quantification of the effect of energy imbalance on bodyweight. Lancet 2011; 378:826-37. [PMID: 21872751 PMCID: PMC3880593 DOI: 10.1016/s0140-6736(11)60812-x] [Citation(s) in RCA: 697] [Impact Index Per Article: 53.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Obesity interventions can result in weight loss, but accurate prediction of the bodyweight time course requires properly accounting for dynamic energy imbalances. In this report, we describe a mathematical modelling approach to adult human metabolism that simulates energy expenditure adaptations during weight loss. We also present a web-based simulator for prediction of weight change dynamics. We show that the bodyweight response to a change of energy intake is slow, with half times of about 1 year. Furthermore, adults with greater adiposity have a larger expected weight loss for the same change of energy intake, and to reach their steady-state weight will take longer than it would for those with less initial body fat. Using a population-averaged model, we calculated the energy-balance dynamics corresponding to the development of the US adult obesity epidemic. A small persistent average daily energy imbalance gap between intake and expenditure of about 30 kJ per day underlies the observed average weight gain. However, energy intake must have risen to keep pace with increased expenditure associated with increased weight. The average increase of energy intake needed to sustain the increased weight (the maintenance energy gap) has amounted to about 0·9 MJ per day and quantifies the public health challenge to reverse the obesity epidemic.
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Affiliation(s)
- Kevin D Hall
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
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Fenton TR, Tough SC, Lyon AW, Eliasziw M, Hanley DA. Causal assessment of dietary acid load and bone disease: a systematic review & meta-analysis applying Hill's epidemiologic criteria for causality. Nutr J 2011; 10:41. [PMID: 21529374 PMCID: PMC3114717 DOI: 10.1186/1475-2891-10-41] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2010] [Accepted: 04/30/2011] [Indexed: 01/19/2023] Open
Abstract
Background Modern diets have been suggested to increase systemic acid load and net acid excretion. In response, alkaline diets and products are marketed to avoid or counteract this acid, help the body regulate its pH to prevent and cure disease. The objective of this systematic review was to evaluate causal relationships between dietary acid load and osteoporosis using Hill's criteria. Methods Systematic review and meta-analysis. We systematically searched published literature for randomized intervention trials, prospective cohort studies, and meta-analyses of the acid-ash or acid-base diet hypothesis with bone-related outcomes, in which the diet acid load was altered, or an alkaline diet or alkaline salts were provided, to healthy human adults. Cellular mechanism studies were also systematically examined. Results Fifty-five of 238 studies met the inclusion criteria: 22 randomized interventions, 2 meta-analyses, and 11 prospective observational studies of bone health outcomes including: urine calcium excretion, calcium balance or retention, changes of bone mineral density, or fractures, among healthy adults in which acid and/or alkaline intakes were manipulated or observed through foods or supplements; and 19 in vitro cell studies which examined the hypothesized mechanism. Urine calcium excretion rates were consistent with osteoporosis development; however calcium balance studies did not demonstrate loss of whole body calcium with higher net acid excretion. Several weaknesses regarding the acid-ash hypothesis were uncovered: No intervention studies provided direct evidence of osteoporosis progression (fragility fractures, or bone strength as measured using biopsy). The supporting prospective cohort studies were not controlled regarding important osteoporosis risk factors including: weight loss during follow-up, family history of osteoporosis, baseline bone mineral density, and estrogen status. No study revealed a biologic mechanism functioning at physiological pH. Finally, randomized studies did not provide evidence for an adverse role of phosphate, milk, and grain foods in osteoporosis. Conclusions A causal association between dietary acid load and osteoporotic bone disease is not supported by evidence and there is no evidence that an alkaline diet is protective of bone health.
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Affiliation(s)
- Tanis R Fenton
- Department of Community Health Sciences, University of Calgary, Calgary, AB, Canada.
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27
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Mero AA, Huovinen H, Matintupa O, Hulmi JJ, Puurtinen R, Hohtari H, Karila TAM. Moderate energy restriction with high protein diet results in healthier outcome in women. J Int Soc Sports Nutr 2010; 7:4. [PMID: 20205751 PMCID: PMC2822830 DOI: 10.1186/1550-2783-7-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2009] [Accepted: 01/25/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The present study compares two different weight reduction regimens both with a moderately high protein intake on body composition, serum hormone concentration and strength performance in non-competitive female athletes. METHODS Fifteen normal weighted women involved in recreational resistance training and aerobic training were recruited for the study (age 28.5 +/- 6.3 yr, height 167.0 +/- 7.0 cm, body mass 66.3 +/- 4.2 kg, body mass index 23.8 +/- 1.8, mean +/- SD). They were randomized into two groups. The 1 KG group (n = 8; energy deficit 1100 kcal/day) was supervised to reduce body weight by 1 kg per week and the 0.5 KG group (n = 7; energy deficit 550 kcal/day) by 0.5 kg per week, respectively. In both groups protein intake was kept at least 1.4 g/kg body weight/day and the weight reduction lasted four weeks. At the beginning of the study the energy need was calculated using food and training diaries. The same measurements were done before and after the 4-week weight reduction period including total body composition (DXA), serum hormone concentrations, jumping ability and strength measurements RESULTS During the 4-week weight reduction period there were no changes in lean body mass and bone mass, but total body mass, fat mass and fat percentage decreased significantly in both groups. The changes were greater in the 1 KG group than in the 0.5 KG group in total body mass (p < 0.001), fat mass (p < 0.001) and fat percentage (p < 0.01). Serum testosterone concentration decreased significantly from 1.8 +/- 1.0 to 1.4 +/- 0.9 nmol/l (p < 0.01) in 1 KG and the change was greater in 1 KG (30%, p < 0.001) than in 0.5 KG (3%). On the other hand, SHBG increased significantly in 1 KG from 63.4 +/- 17.7 to 82.4 +/- 33.0 nmol/l (p < 0.05) during the weight reducing regimen. After the 4-week period there were no changes in strength performance in 0.5 KG group, however in 1 KG maximal strength in bench press decreased (p < 0.05) while endurance strength in squat and counter movement jump improved (p < 0.05) CONCLUSION It is concluded that a weight reduction by 0.5 kg per week with ~1.4 g protein/kg body weight/day can be recommended to normal weighted, physically active women instead of a larger (e.g. 1 kg per week) weight reduction because the latter may lead to a catabolic state. Vertical jumping performance is improved when fat mass and body weight decrease. Thus a moderate weight reduction prior to a major event could be considered beneficial for normal built athletes in jumping events.
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Affiliation(s)
- Antti A Mero
- Department of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland
| | - Heikki Huovinen
- Department of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland
| | - Olle Matintupa
- Department of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland
| | - Juha J Hulmi
- Department of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland
| | - Risto Puurtinen
- Department of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland
| | | | - Tuomo AM Karila
- Hospital Orton, Helsinki, Finland
- Orthopaedic Department, Gisborne Hospital, New Zealand
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Ceglia L, Harris SS, Abrams SA, Rasmussen HM, Dallal GE, Dawson-Hughes B. Potassium bicarbonate attenuates the urinary nitrogen excretion that accompanies an increase in dietary protein and may promote calcium absorption. J Clin Endocrinol Metab 2009; 94:645-53. [PMID: 19050051 PMCID: PMC2730228 DOI: 10.1210/jc.2008-1796] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Protein is an essential component of muscle and bone. However, the acidic byproducts of protein metabolism may have a negative impact on the musculoskeletal system, particularly in older individuals with declining renal function. OBJECTIVE We sought to determine whether adding an alkaline salt, potassium bicarbonate (KHCO3), allows protein to have a more favorable net impact on intermediary indices of muscle and bone conservation than it does in the usual acidic environment. DESIGN We conducted a 41-d randomized, placebo-controlled, double-blind study of KHCO3 or placebo with a 16-d phase-in and two successive 10-d metabolic diets containing low (0.5 g/kg) or high (1.5 g/kg) protein in random order with a 5-d washout between diets. SETTING The study was conducted in a metabolic research unit. PARTICIPANTS Nineteen healthy subjects ages 54-82 yr participated. INTERVENTION KHCO3 (up to 90 mmol/d) or placebo was administered for 41 d. MAIN OUTCOME MEASURES We measured 24-h urinary nitrogen excretion, IGF-I, 24-h urinary calcium excretion, and fractional calcium absorption. RESULTS KHCO3 reduced the rise in urinary nitrogen excretion that accompanied an increase in protein intake (P = 0.015) and was associated with higher IGF-I levels on the low-protein diet (P = 0.027) with a similar trend on the high-protein diet (P = 0.050). KHCO3 was also associated with higher fractional calcium absorption on the low-protein diet (P = 0.041) with a similar trend on the high-protein diet (P = 0.064). CONCLUSIONS In older adults, KHCO3 attenuates the protein-induced rise in urinary nitrogen excretion, and this may be mediated by IGF-I. KHCO3 may also promote calcium absorption independent of the dietary protein content.
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Affiliation(s)
- Lisa Ceglia
- Jean Mayer United States Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, 711 Washington Street, Boston, Massachusetts 02111, USA.
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Dawson-Hughes B, Harris SS, Ceglia L. Alkaline diets favor lean tissue mass in older adults. Am J Clin Nutr 2008; 87:662-5. [PMID: 18326605 PMCID: PMC2597402 DOI: 10.1093/ajcn/87.3.662] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND Maintaining muscle mass while aging is important to prevent falls and fractures. Metabolic acidosis promotes muscle wasting, and the net acid load from diets that are rich in net acid-producing protein and cereal grains relative to their content of net alkali-producing fruit and vegetables may therefore contribute to a reduction in lean tissue mass in older adults. OBJECTIVE We aimed to determine whether there was an association of 24-h urinary potassium and an index of fruit and vegetable content of the diet with the percentage lean body mass (%LBM) or change in %LBM in older subjects. DESIGN Subjects were 384 men and women > or =65 y old who participated in a 3-y trial comparing calcium and vitamin D with placebo. Potassium was measured in 24-h urine collections at baseline. The %LBM, defined as total body nonfat, nonbone tissue weight/weight x 100, was measured by using dual-energy X-ray absorptiometry at baseline and at 3 y. Physical activity, height, and weight were assessed at baseline and at 3 y. RESULTS At baseline, the mean urinary potassium excretion was 67.0 +/- 21.1 mmol/d. Urinary potassium (mmol/d) was significantly positively associated with %LBM at baseline (beta = 0.033, P = 0.006; adjusted for sex, weight, and nitrogen excretion) but not with 3-y change in %LBM. Over the 3-y study, %LBM increased by 2.6 +/- 3.6%. CONCLUSION Higher intake of foods rich in potassium, such as fruit and vegetables, may favor the preservation of muscle mass in older men and women.
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Affiliation(s)
- Bess Dawson-Hughes
- Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, MA, USA
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30
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31
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Dashti HM, Mathew TC, Khadada M, Al-Mousawi M, Talib H, Asfar SK, Behbahani AI, Al-Zaid NS. Beneficial effects of ketogenic diet in obese diabetic subjects. Mol Cell Biochem 2007; 302:249-56. [PMID: 17447017 DOI: 10.1007/s11010-007-9448-z] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2006] [Accepted: 03/07/2007] [Indexed: 12/24/2022]
Abstract
OBJECTIVE Obesity is closely linked to the incidence of type II diabetes. It is found that effective management of body weight and changes to nutritional habits especially with regard to the carbohydrate content and glycemic index of the diet have beneficial effects in obese subjects with glucose intolerance. Previously we have shown that ketogenic diet is quite effective in reducing body weight. Furthermore, it favorably alters the cardiac risk factors even in hyperlipidemic obese subjects. In this study the effect of ketogenic diet in obese subjects with high blood glucose level is compared to those with normal blood glucose level for a period of 56 weeks. MATERIALS AND METHODS A total of 64 healthy obese subjects with body mass index (BMI) greater than 30, having high blood glucose level and those subjects with normal blood glucose level were selected in this study. The body weight, body mass index, blood glucose level, total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, urea and creatinine were determined before and at 8, 16, 24, 48, and 56 weeks after the administration of the ketogenic diet. RESULTS The body weight, body mass index, the level of blood glucose, total cholesterol, LDL-cholesterol, triglycerides, and urea showed a significant decrease from week 1 to week 56 (P < 0.0001), whereas the level of HDL-cholesterol increased significantly (P < 0.0001). Interestingly these changes were more significant in subjects with high blood glucose level as compared to those with normal blood glucose level. The changes in the level of creatinine were not statistically significant. CONCLUSION This study shows the beneficial effects of ketogenic diet in obese diabetic subjects following its long-term administration. Furthermore, it demonstrates that in addition to its therapeutic value, low carbohydrate diet is safe to use for a longer period of time in obese diabetic subjects.
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Affiliation(s)
- Hussein M Dashti
- Department of Surgery, Faculty of Medicine, Kuwait University, PO Box 24923, 13110 Safat, Kuwait.
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32
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Manninen AH. Very-low-carbohydrate diets and preservation of muscle mass. Nutr Metab (Lond) 2006; 3:9. [PMID: 16448570 PMCID: PMC1373635 DOI: 10.1186/1743-7075-3-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2006] [Accepted: 01/31/2006] [Indexed: 11/13/2022] Open
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Noakes M, Foster PR, Keogh JB, James AP, Mamo JC, Clifton PM. Comparison of isocaloric very low carbohydrate/high saturated fat and high carbohydrate/low saturated fat diets on body composition and cardiovascular risk. Nutr Metab (Lond) 2006; 3:7. [PMID: 16403234 PMCID: PMC1368980 DOI: 10.1186/1743-7075-3-7] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2005] [Accepted: 01/11/2006] [Indexed: 11/13/2022] Open
Abstract
Background It is speculated that high saturated fat very low carbohydrate diets (VLCARB) have adverse effects on cardiovascular risk but evidence for this in controlled studies is lacking. The objective of this study was to compare, under isocaloric conditions, the effects of a VLCARB to 2 low saturated fat high carbohydrate diets on body composition and cardiovascular risk. Methods Eighty three subjects, 48 ± 8 y, total cholesterol 5.9 ± 1.0 mmol/L, BMI 33 ± 3 kg/m2 were randomly allocated to one of 3 isocaloric weight loss diets (6 MJ) for 8 weeks and on the same diets in energy balance for 4 weeks: Very Low Fat (VLF) (CHO:Fat:Protein; %SF = 70:10:20; 3%), High Unsaturated Fat (HUF) = (50:30:20; 6%), VLCARB (4:61:35; 20%) Results Percent fat mass loss was not different between diets VLCARB -4.5 ± 0.5, VLF-4.0 ± 0.5, HUF -4.4 ± 0.6 kg). Lean mass loss was 32-31% on VLCARB and VLF compared to HUF (21%) (P < 0.05). LDL-C increased significantly only on VLCARB by 7% (p < 0.001 compared with the other diets) but apoB was unchanged on this diet and HDL-C increased relative to the other 2 diets. Triacylglycerol was lowered by 0.73 ± 0.12 mmol/L on VLCARB compared to -0.15 ± 0.07 mmol/L on HUF and -0.06 ± 0.13 mmol/L on VLF (P < 0.001). Plasma homocysteine increased 6.6% only on VLCARB (P = 0.026). VLCARB lowered fasting insulin 33% compared to a 19% fall on HUF and no change on VLF (P < 0.001). The VLCARB meal also provoked significantly lower post prandial glucose and insulin responses than the VLF and HUF meals. All diets decreased fasting glucose, blood pressure and CRP (P < 0.05). Conclusion Isocaloric VLCARB results in similar fat loss than diets low in saturated fat, but are more effective in improving triacylglycerols, HDL-C, fasting and post prandial glucose and insulin concentrations. VLCARB may be useful in the short-term management of subjects with insulin resistance and hypertriacylglycerolemia.
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Affiliation(s)
- Manny Noakes
- CSIRO Health Sciences and Nutrition, Adelaide, Australia
| | - Paul R Foster
- CSIRO Health Sciences and Nutrition, Adelaide, Australia
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Volek JS, Sharman MJ, Gómez AL, Judelson DA, Rubin MR, Watson G, Sokmen B, Silvestre R, French DN, Kraemer WJ. Comparison of energy-restricted very low-carbohydrate and low-fat diets on weight loss and body composition in overweight men and women. Nutr Metab (Lond) 2004; 1:13. [PMID: 15533250 PMCID: PMC538279 DOI: 10.1186/1743-7075-1-13] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2004] [Accepted: 11/08/2004] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVE: To compare the effects of isocaloric, energy-restricted very low-carbohydrate ketogenic (VLCK) and low-fat (LF) diets on weight loss, body composition, trunk fat mass, and resting energy expenditure (REE) in overweight/obese men and women. DESIGN: Randomized, balanced, two diet period clinical intervention study. Subjects were prescribed two energy-restricted (-500 kcal/day) diets: a VLCK diet with a goal to decrease carbohydrate levels below 10% of energy and induce ketosis and a LF diet with a goal similar to national recommendations (%carbohydrate:fat:protein = ~60:25:15%). SUBJECTS: 15 healthy, overweight/obese men (mean +/- s.e.m.: age 33.2 +/- 2.9 y, body mass 109.1 +/- 4.6 kg, body mass index 34.1 +/- 1.1 kg/m2) and 13 premenopausal women (age 34.0 +/- 2.4 y, body mass 76.3 +/- 3.6 kg, body mass index 29.6 +/- 1.1 kg/m2). MEASUREMENTS: Weight loss, body composition, trunk fat (by dual-energy X-ray absorptiometry), and resting energy expenditure (REE) were determined at baseline and after each diet intervention. Data were analyzed for between group differences considering the first diet phase only and within group differences considering the response to both diets within each person. RESULTS: Actual nutrient intakes from food records during the VLCK (%carbohydrate:fat:protein = ~9:63:28%) and the LF (~58:22:20%) were significantly different. Dietary energy was restricted, but was slightly higher during the VLCK (1855 kcal/day) compared to the LF (1562 kcal/day) diet for men. Both between and within group comparisons revealed a distinct advantage of a VLCK over a LF diet for weight loss, total fat loss, and trunk fat loss for men (despite significantly greater energy intake). The majority of women also responded more favorably to the VLCK diet, especially in terms of trunk fat loss. The greater reduction in trunk fat was not merely due to the greater total fat loss, because the ratio of trunk fat/total fat was also significantly reduced during the VLCK diet in men and women. Absolute REE (kcal/day) was decreased with both diets as expected, but REE expressed relative to body mass (kcal/kg), was better maintained on the VLCK diet for men only. Individual responses clearly show the majority of men and women experience greater weight and fat loss on a VLCK than a LF diet. CONCLUSION: This study shows a clear benefit of a VLCK over LF diet for short-term body weight and fat loss, especially in men. A preferential loss of fat in the trunk region with a VLCK diet is novel and potentially clinically significant but requires further validation. These data provide additional support for the concept of metabolic advantage with diets representing extremes in macronutrient distribution.
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Affiliation(s)
- JS Volek
- Human Performance Laboratory, Department of Kinesiology, University of Connecticut, 2095 Hillside Road, Unit-1110, Storrs, CT 06269-1110, USA
| | - MJ Sharman
- Human Performance Laboratory, Department of Kinesiology, University of Connecticut, 2095 Hillside Road, Unit-1110, Storrs, CT 06269-1110, USA
| | - AL Gómez
- Human Performance Laboratory, Department of Kinesiology, University of Connecticut, 2095 Hillside Road, Unit-1110, Storrs, CT 06269-1110, USA
| | - DA Judelson
- Human Performance Laboratory, Department of Kinesiology, University of Connecticut, 2095 Hillside Road, Unit-1110, Storrs, CT 06269-1110, USA
| | - MR Rubin
- Human Performance Laboratory, Department of Kinesiology, University of Connecticut, 2095 Hillside Road, Unit-1110, Storrs, CT 06269-1110, USA
| | - G Watson
- Human Performance Laboratory, Department of Kinesiology, University of Connecticut, 2095 Hillside Road, Unit-1110, Storrs, CT 06269-1110, USA
| | - B Sokmen
- Human Performance Laboratory, Department of Kinesiology, University of Connecticut, 2095 Hillside Road, Unit-1110, Storrs, CT 06269-1110, USA
| | - R Silvestre
- Human Performance Laboratory, Department of Kinesiology, University of Connecticut, 2095 Hillside Road, Unit-1110, Storrs, CT 06269-1110, USA
| | - DN French
- Human Performance Laboratory, Department of Kinesiology, University of Connecticut, 2095 Hillside Road, Unit-1110, Storrs, CT 06269-1110, USA
| | - WJ Kraemer
- Human Performance Laboratory, Department of Kinesiology, University of Connecticut, 2095 Hillside Road, Unit-1110, Storrs, CT 06269-1110, USA
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Sondike SB, Copperman N, Jacobson MS. Effects of a low-carbohydrate diet on weight loss and cardiovascular risk factor in overweight adolescents. J Pediatr 2003; 142:253-8. [PMID: 12640371 DOI: 10.1067/mpd.2003.4] [Citation(s) in RCA: 173] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
OBJECTIVES To compare the effects of a low-carbohydrate (LC) diet with those of a low-fat (LF) diet on weight loss and serum lipids in overweight adolescents. DESIGN A randomized, controlled 12-week trial. SETTING Atherosclerosis prevention referral center. METHODS Random, nonblinded assignment of participants referred for weight management. The study group (LC) (n = 16) was instructed to consume <20 g of carbohydrate per day for 2 weeks, then <40 g/day for 10 weeks, and to eat LC foods according to hunger. The control group (LF) (n = 14) was instructed to consume <30% of energy from fat. Diet composition and weight were monitored and recorded every 2 weeks. Serum lipid profiles were obtained at the start of the study and after 12 weeks. RESULTS The LC group lost more weight (mean, 9.9 +/- 9.3 kg vs 4.1 +/- 4.9 kg, P <.05) and had improvement in non-HDL cholesterol levels (P <.05). There was improvement in LDL cholesterol levels (P <.05) in the LF group but not in the LC group. There were no adverse effects on the lipid profiles of participants in either group. CONCLUSIONS The LC diet appears to be an effective method for short-term weight loss in overweight adolescents and does not harm the lipid profile.
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Affiliation(s)
- Stephen B Sondike
- Division of Adolescent Medicine, Schneider Children's Hospital, New Hyde Park, New York 10128, USA
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Interactions protéines — Énergie. NUTR CLIN METAB 2000. [DOI: 10.1016/s0985-0562(00)80028-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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van Gemert WG, Westerterp KR, van Acker BA, Wagenmakers AJ, Halliday D, Greve JM, Soeters PB. Energy, substrate and protein metabolism in morbid obesity before, during and after massive weight loss. Int J Obes (Lond) 2000; 24:711-8. [PMID: 10878677 DOI: 10.1038/sj.ijo.0801230] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To investigate the effect of surgically induced weight loss on energy, substrate and protein metabolism of morbidly obese patients. DESIGN A prospective, clinical intervention study of morbidly obese patients before and after surgical treatment. SUBJECTS Eight morbidly obese patients (BMI 47.88+/-7.03). METHODS Total energy expenditure (TEE; doubly labeled water method), sleeping metabolic rate (SMR; respiration chamber), body composition (deuterium oxide component of doubly labeled water), substrate metabolism (48 h dietary records, 48 h urine collection and gaseous exchange in the respiration chamber) and whole body protein turnover (primed-continuous infusion of L-[1-13C]-leucine) were measured before, 3 and 12 months after vertical banded gastroplasty (VBG). RESULTS The TEE decreased as a result of a decreased SMR (64%) and non-SMR (36%; P=0.001). SMR as a function of fat-free mass (FFM) decreased after weight loss (P<0.05). The physical activity index (PAI), defined as TEE/SMR, was low and was not influenced by weight loss. Protein and carbohydrate oxidation decreased significantly after VBG (P<0.05), although 3 months after VBG protein oxidation did not decrease enough to prevent loss of FFM. The energy used for protein turnover was approximately 24% of SMR and did not change after weight loss. CONCLUSIONS Compensatory processes that oppose weight loss of morbidly obese patients exist, as demonstrated by the disproportional reduction of SMR, and a low PAI. Protein turnover is not a major contributor to the disproportional reduction of SMR.
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Affiliation(s)
- W G van Gemert
- Departments of Surgery and Human Biology, University Hospital Maastricht, PO box 5800, 6202 AZ, Maastricht, The Netherlands.
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