Effect of potassium citrate supplementation or increased fruit and vegetable intake on bone metabolism in healthy postmenopausal women: a randomized controlled trial

Potassium: A Frontier in Osteoporosis

Osteoporosis is a significant public health concern, particularly in aging populations, leading to fractures, decreased mobility, and reduced quality of life. While calcium and vitamin D have long been recognized as essential for bone health, emerging research suggests that potassium may play a crucial role in maintaining bone density and preventing osteoporosis. This manuscript explores the relationship between potassium and osteoporosis, delving into the mechanisms, epidemiological evidence, and potential therapeutic implications of potassium in bone health. Furthermore, the manuscript discusses the sources of dietary potassium, its impact on bone metabolism, and the future directions in research and clinical practice regarding potassium's role in osteoporosis management.

Association of dietary carbohydrate and fiber ratio with postmenopausal bone mineral density and prevalence of osteoporosis: A cross-sectional study

BACKGROUND

This study aimed to investigate the associations of carbohydrate to dietary fiber ratio with bone mineral density (BMD) and the prevalence of osteoporosis in postmenopausal women.

METHODS

This cross-sectional study retrieved the data of 2829 postmenopausal women from the National Health and Nutrition Examination Survey (NHANES) database. Weighted univariable logistic regression models were used to investigate the correlations of carbohydrate, dietary fiber, or carbohydrate to fiber ratio with osteoporosis.

RESULTS

Higher dietary fiber intake was correlated with decreased odds ratio of osteoporosis [odds ratio(OR) = 0.96, 95% confidence interval (CI): 0.93 to 0.99]. The odds ratio of osteoporosis in postmenopausal women was elevated as the increase of carbohydrate to fiber ratio (OR = 1.80, 95%CI: 1.10 to 2.96). Carbohydrate to fiber ratio >17.09 was related to increased odds ratio of osteoporosis (OR = 1.63, 95%CI: 1.04 to 2.56). Compared to the carbohydrate to fiber ratio ≤11.59 group, carbohydrate to fiber ratio >17.09 was associated with decreased total femur BMD (β = -0.015, 95%CI: -0.028 to -0.001) and femur neck BMD (β = -0.020, 95%CI: -0.033 to -0.006) in postmenopausal women. The femur neck BMD in postmenopausal women was decreased with the increase of carbohydrate to fiber ratio (β = -0.015, 95%CI: -0.028 to -0.001).

CONCLUSION

In postmenopausal women, a high carbohydrate/fiber ratio >17.09 is associated with an increased risk of osteoporosis and lower hip BMD and high fiber intake is associated with less osteoporosis and higher hip BMD.

ABO blood type correlates with risk and protective factors for chronic suppurative otitis media

BACKGROUND

ABO blood type associated with differentiated onset of infectious diseases.

AIMS/OBJECTIVE

To investigate whether people with different blood types were vulnerable in developing chronic otitis media (CSOM) and if the risk and protective factors varied among them.

MATERIAL AND METHODS

The study was a case-control study that included 206 participants in the case group and 210 in the control group. Stratified analysis for blood type was adopted.

RESULTS

Patients with different blood types were insignificantly different in the incidence of CSOM. Upper respiratory tract infection (URTI, OR = 21.81, 95% CI: 4.80-99.06), socioeconomic status (OR = 3.02, 95% CI: 1.35-6.74), and were risk factors in blood type A. In blood type B, smoking and urban residence were risk factors. The OR (95% CI) were 11.42 (2.77-47.08), and 0.14 (0.03-0.65). Urban residence, BMI and blood calcium increase, male gender were protective factors for different blood types.

CONCLUSIONS AND SIGNIFICANCE

Our study identified the risk and protective factors for CSOM among different blood types. The findings might provide new insights into taking precautions against CSOM in people of different blood types.

How do carbohydrate quality indices influence on bone mass density in postmenopausal women? A case-control study

BACKGROUND

Carbohydrates are the primary energy source in Asian countries, including Iran. An emerging method can be used to measure the quality of carbohydrates, including the carbohydrate quality index (CQI), which includes a variety of components. Low-carbohydrate diet score (LCDS) has been proposed as a new method of scoring micronutrient intake that could provide a reasonable explanation for the link between diet and the risk of chronic diseases.

OBJECTIVE

This study aimed to investigate the relationship between CQI, LCDS, glycemic index (GI), glycemic load (GL), insulin load (IL), and insulin index (II) with bone mass density (BMD) in postmenopausal women.

METHOD

In this case-control study, 131 postmenopausal women with osteoporosis/osteopenia and 131 healthy postmenopausal women aged 45-65 participated. The dual-energy X-ray absorptiometry (DEXA) method measured the BMD of the lumbar vertebrae and femoral neck. A validated semi-quantitative food frequency questionnaire was used to assess dietary intake. Logistic regression were used to evaluate the relation between GI, GL, II, IL, CQI, and LCDS with BMD.

RESULTS

Diets with higher GI increased the risk of osteopenia and osteoporosis, but LCDS and CQI decreased the risk of osteopenia and osteoporosis.

CONCLUSION

These findings suggest that a higher intake of fruits and vegetables and receiving various dietary vitamins, minerals, and antioxidant compounds may be a useful way to prevent osteopenia in Iranian women.

The Relationship between Dietary Na/K Ratio and Bone Mineral Density in Korean Middle-Aged Women

BACKGROUND

Dietary Na+ or Na+/K+ ratio has been reported to be associated with bone mineral density (BMD). However, this remains unclear, and only a few studies have been reported on the Korean population. Therefore, this study aimed to determine the association between dietary Na+, K+, and Na+/K+ ratios and BMD in middle-aged Korean women.

METHODS

This study used data from the Korea National Health and Nutrition Examination Survey 2008-2011. A total of 3,690 women aged >50 years were included. Study participants were classified into quartiles (lowest quartile Q1-highest quartile Q4) according to dietary Na+, K+, and Na+/K+ ratio, and we examined the association of these parameters with BMD. Total femur and lumbar spine BMD were measured using dual-energy X-ray absorptiometry. Multiple linear regression analyses were performed using IBM SPSS ver. 19.0.

RESULTS

The mean age was 62 years, and a significant negative trend in the β-coefficient regarding dietary Na+ was only observed in the total femur BMD. However, the total femur and lumbar spine BMD decreased from Q1 to Q4 regarding the dietary Na+/K+ ratio (P-value for trend: 0.044 for total femur BMD and 0.002 for lumbar spine BMD).

CONCLUSION

A significant negative trend in the β-coefficient for both total femur and lumbar spine BMD was observed regarding the Na+/K+ ratio. Therefore, based on the results of this study, a higher dietary Na+/K+ ratio may be associated with a lower BMD.

Chronic Sub-Clinical Systemic Metabolic Acidosis - A Review with Implications for Clinical Practice

When arterial serum pH remains near the lower pH limit of 7.35 for protracted periods of time, a low-grade, sub-clinical form of acidosis results, referred to in this review as chronic, sub-clinical, systemic metabolic acidosis (CSSMA). This narrative review explores the scientific basis for CSSMA, its consequences for health, and potential therapeutic interventions. The major etiology of CSSMA is the shift away from the ancestral, alkaline diet which was rich in fruit and vegetables, toward the contemporary, acidogenic 'Westernized' diet characterized by higher animal protein consumption and lack of base forming minerals. Urine pH is reduced with high dietary acid load and may be a convenient marker of CSSMA. Evidence suggests further that CSSMA negatively influences cortisol levels potentially contributing significantly to the pathophysiology thereof. Both CSSMA and high dietary acid load are associated with the risk and prognosis of various chronic diseases. Clinical trials show that CSSMA can be addressed successfully through alkalizing the diet by increasing fruit and vegetable intake and/or supplementing with alkaline minerals. This review confirms the existence of a significant body of evidence regarding this low-grade form of acidosis as well as evidence to support its diverse negative implications for health, and concludes that CSSMA is a condition warranting further research.

Urinary Potential Renal Acid Load (uPRAL) among Vegans Versus Omnivores and Its Association with Bone Health in the Cross-Sectional Risks and Benefits of a Vegan Diet Study

Both veganism and high dietary acid load are linked to unfavorable bone health. However, the specific role of dietary alkali or acid load for the bone health of vegans is so far unknown. Thus, the renal biomarker for dietary acid or alkali load, i.e., urinary potential renal acid load (uPRAL), was measured in 24 h urine samples of 34 vegans and 35 omnivores (50.7% males). Bone health was assessed via calcaneal quantitative ultrasound. Associations between uPRAL and bone health indices were examined using multivariable general linear models. Compared to omnivores, vegans had a significantly lower uPRAL (mean difference = −34.5 mEq/24 h, p < 0.0001), a lower 24 h urinary phosphate excretion (p = 0.0004), a lower 24 h urinary sulfate excretion (p = 0.01), and a higher urine pH value (p < 0.0001). Broadband ultrasound attenuation (BUA) was lower among vegans versus omnivores (p = 0.037), yet it was not associated with uPRAL irrespective of adjustments. This study confirms different acid-base profiles of vegans and omnivores, with a pronounced alkaline excess among vegans and a rather low acid load among a group of omnivores with moderate protein intake. Within this spectrum of alkaline to low acid load, no association with bone health was found.

Modifiable risk factors for bone health & fragility fractures

Osteoporosis is an ageing disorder characterised by poor microstructural architecture of the bone and an increase in the risk of fragility fractures, which often leads to hospitalisation and eventually a loss of mobility and independence. By 2050, it is estimated that more than 30 million people in Europe will be affected by bone diseases, and European hospitalisation alone can approximately cost up to 3.5 billion euros each year [1]. Although inherited variation in bone mineral density (BMD) is pre-determined by up to 85% [2], there is a window of opportunity to optimise BMD and reduce fracture risk through key modifiable lifestyle factors during the life course. An optimal diet rich in micronutrients, such as calcium, vitamin D, and potassium, has long been considered an important modifiable component of bone health, which is attributed to their direct roles within bone metabolism. Recently, there has been emerging evidence to suggest that protein and even an adequate intake of fruit and vegetables may also play an important role in improving BMD [3,4]. Maintaining a physically active lifestyle is not only protective from non-communicable diseases such as cardiovascular disease but it also has been shown to lessen the risk of fractures later in life, thereby making it an imperative modifiable factor for bone health, particularly as it also supports peak bone mass attainment during childhood/adolescence and can facilitate the maintenance of bone mass throughout adulthood [5]. Other key lifestyle factors that could be potentially modified to reduce the risk of osteoporosis or osteoporotic fractures later in life include smoking status, alcohol intake, and body composition [6]. Therefore, the principle aim of this review is to highlight the recent evidence pertaining to modifiable lifestyle factors that contribute to optimal bone health and the prevention of fragility fractures in later life.

Introductory Chapter: Potassium in Human Health

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Preclinical and Clinical Evidence of Effect of Acid on Bone Health

Acid can have ill effect on bone health in the absence of frank clinical acidosis but affecting the bone mioneral matrix and bone cells via complex pathways botyh ascute;y and chronically. While the reaction of bone to an acid load is conserved in evolution and is adaptive, the capacity can be overwhelmed resulting in dire consequences. The preclinical an clincl evidence of the acdi effect on bone is very convincing and the clinical evidence in both association and interventiopn studies are also quite credible, The adverse effects of acid on bone is underappreoicated, under-investigated, and the potential benefits of alkali therapy is not generrally known.

The Impact of Major and Trace Elements in Serum and Bone on Dual-Energy X-Ray Absorptiometry-Derived Hip Strength

The purpose of this study was to establish associations between both serum levels and bone content of a wide range of elements (Na, K, P, Ca, Mg, Zn, Cu, Cr, Mn, Fe, and Pb), with hip strength (HS) indices derived from dual-energy X-ray absorptiometry (DXA). The study population consisted of a number of male patients aged 56-77 years following hip replacement due to osteoarthritis of the hip. Bone specimens were taken from the femoral head and neck during arthroplasty. The elemental analyses were carried out using coupled plasma optical emission spectrometry. The following DXA-HS parameters were assessed: buckling ratio (BR), cross-sectional area (CSA) and its moment of inertia (CSMI), section modulus, and Femoral Strength Index (FSI). Age was positively correlated with Na, K, and Cu in the bone. Ca in the bone was positively associated with BR and negatively with SM and CSMI. Of all the DXA-HS parameters, the weakest associations of elements in the bone were found with FSI and the strongest with BR. Among the elements in the serum, the strongest negative associations were found for K, Cr, Mn, and Zn with CSA, while the majority of bone elements were associated either positively (Ca, P, Mg, Zn, and Cu) or negatively (Mn, Fe, Pb, and Cr) with BR. In conclusion, the interactions between individual elements in blood serum and bone with DXA-HS could not be unequivocally established.

Short-Term Supplemental Dietary Potassium from Potato and Potassium Gluconate: Effect on Calcium Retention and Urinary pH in Pre-Hypertensive-to-Hypertensive Adults

Potassium supplementation has been associated with reduced urinary calcium (Ca) excretion and increased Ca balance. Dietary interventions assessing the impact of potassium on bone are lacking. In this secondary analysis of a study designed primarily to determine blood pressure effects, we assessed the effects of potassium intake from potato sources and a potassium supplement on urinary Ca, urine pH, and Ca balance. Thirty men (n = 15) and women (n = 15) with a mean ± SD age and BMI of 48.2 ± 15 years and 31.4 ± 6.1 kg/m², respectively, were enrolled in a cross-over, randomized control feeding trial. Participants were assigned to a random order of four 16-day dietary potassium interventions including a basal diet (control) of 2300 mg/day (~60 mmol/day) of potassium, and three phases of an additional 1000 mg/day (3300 mg/day(~85 mmol/day) total) of potassium in the form of potatoes (baked, boiled, or pan-heated), French fries (FF), or a potassium (K)-gluconate supplement. Calcium intake for all diets was approximately 700–800 mg/day. Using a mixed model ANOVA there was a significantly lower urinary Ca excretion in the K-gluconate phase (96 ± 10 mg/day) compared to the control (115 ± 10 mg/day; p = 0.027) and potato (114 ± 10 mg/day; p = 0.033). In addition, there was a significant difference in urinary pH between the supplement and control phases (6.54 ± 0.16 vs. 6.08 ± 0.18; p = 0.0036). There were no significant differences in Ca retention. An increased potassium intake via K-gluconate supplementation may favorably influence urinary Ca excretion and urine pH. This trial was registered at ClinicalTrials.gov as NCT02697708.

Increasing Vegetable Intake Decreases Urinary Acidity and Bone Resorption Marker in Overweight and Obese Adults: An 8-Week Randomized Controlled Trial

BACKGROUND

Controlled intervention trials are needed to confirm a positive association from epidemiological studies between vegetable consumption and bone health.

OBJECTIVE

We investigated whether providing vegetables at the Dietary Guidelines for Americans (DGA) recommended amount affects excretion of acid and calcium in urine and bone turnover markers in serum in adults with low vegetable intake.

METHODS

In total, 102 adults (19 males and 83 females, age 18-65 y, BMI ≥25 kg/m2) consuming ≤1 serving of vegetables (128 g raw leafy or 64 g cooked vegetables) per d were recruited in a 2-arm, parallel, randomized, controlled, and community-based 8-wk feeding intervention trial. The 2 arms included a vegetable intervention (VI) during which participants received extra vegetables (∼270 g/d) and an attention control (CON) group that conducted only the testing visits. Measurements included nutrient intake, plasma carotenoids, and bone-related markers in serum and urine. Differences between CON and VI at week 8 were tested using the ANCOVA with baseline values as a covariate.

RESULTS

Compared with CON, carotenoid intake (mean ± SD) was higher (6.4 ± 3.4 compared with 2.0 ± 1.2 mg/d) (P < 0.01) and dietary potential renal acid load was lower (20 ± 13 compared with 3.4 ± 14 mEq/d) (P < 0.01) in VI. Compared with CON at week 8, urine titratable acid and Mg were 24 and 26% lower, respectively, while urine pH was 3% greater (P < 0.05) and serum C-terminal telopeptide of type I collagen (CTX) was 19% lower in VI. There were no group differences in serum concentrations of propeptide of type 1 procollagen and tartrate-resistant acid phosphatase or urinary excretion of deoxypyridinoline and CTX.

CONCLUSIONS

Consumption of vegetables at the DGA-recommended amount by adults with low vegetable intake potentially benefits bone health. This trial was registered at clinicaltrials.gov as NCT02585102.

The Role of Diet in Bone and Mineral Metabolism and Secondary Hyperparathyroidism

Bone disorders are a common complication of chronic kidney disease (CKD), obesity and gut malabsorption. Secondary hyperparathyroidism (SHPT) is defined as an appropriate increase in parathyroid hormone (PTH) secretion, driven by either reduced serum calcium or increased phosphate concentrations, due to an underlying condition. The available evidence on the effects of dietary advice on secondary hyperparathyroidism confirms the benefit of a diet characterized by decreased phosphate intake, avoiding low calcium and vitamin D consumption (recommended intakes 1000-1200 mg/day and 400-800 UI/day, respectively). In addition, low protein intake in CKD patients is associated with a better control of SHPT risk factors, although its strength in avoiding hyperphosphatemia and the resulting outcomes are debated, mostly for dialyzed patients. Ultimately, a consensus on the effect of dietary acid loads in the prevention of SHPT is still lacking. In conclusion, a reasonable approach for reducing the risk for secondary hyperparathyroidism is to individualize dietary manipulation based on existing risk factors and concomitant medical conditions. More studies are needed to evaluate long-term outcomes of a balanced diet on the management and prevention of secondary hyperparathyroidism in at-risk patients at.

The link between plant-based diet indices with biochemical markers of bone turn over, inflammation, and insulin in Iranian older adults

BACKGROUND

The association of plant-based diets and biomarkers of bone, insulin, and inflammation is still unclear.

OBJECTIVES

We investigated the associations between biomarkers of bone, insulin, and inflammation and three plant-based diet indices: an overall plant-based diet index (PDI); a healthy plant-based diet index (hPDI); and an unhealthy plant-based diet index (uPDI).

METHODS

We included 178 elderly subjects who referred to health centers in Tehran. Blood and urine samples were collected to measure osteocalcin. The Human C-telopeptide of type Ⅰ collagen (u-CTX-I), highly sensitive C-reactive protein (hs-CRP), parathyroid hormone (PTH), 25(OH) D, and insulin resistance and sensitivity. We created an overall PDI, hPDI, and uPDI from semi-quantitative food frequency questionnaire (FFQ) data.

RESULTS

Dietary groups of Vegetables (r = .15, p = .03), nuts (r = .16, p = .03), dairy (r = .25, p = .001), eggs (r = .27, p < .001), red meat, and animal products (r = .25, p = .001) were directly correlated with osteocalcin. Refined grains were also had a positive association with serum insulin concentration (r = .14, p = .04). PTH levels are inversely associated with PDI score (β = -0.18, p = .01). Also, serum insulin concentration was negatively associated with PDI score (β = -0.10, p = .04). Urine CTX-1 levels were significantly associated with hPDI score (β = -0.06, p = .04). u-CTX-1 levels are inversely associated with uPDI score. This significance did not change with the adjustment of the confounders (β = -0.28, p < .001).

CONCLUSIONS

More adherence to PDI and hPDI and less in uPDI may have a beneficial effect on biomarkers of bone, inflammation, and insulin thus preserving chronic diseases.

Effect of Acid or Base Interventions on Bone Health: A Systematic Review, Meta-Analysis, and Meta-Regression

Osteoporosis is a global health issue among the aging population. The effect of the acid or base interventions on bone health remains controversial. This study performed a systematic review and meta-analysis to investigate effects of acidic diets and alkaline supplements on bone health simultaneously. We conducted a comprehensive literature search in 5 available databases and 1 registered clinical trial system to identify randomized controlled trials (RCTs) that assessed effects of the acid-base intervention on bone health. Depending on heterogeneity across studies, the pooled effects were calculated by fixed-effects or random-effects models. The present study included 13 acidic diet intervention studies and 13 alkaline supplement studies for final quantitative assessments. The meta-analysis showed that acidic diets significantly increased net acid excretion [NAE; standardized mean difference (SMD) = 2.99; P = 0.003] and urinary calcium excretion (SMD = 0.47, P < 0.00001) but had no significant effect on bone turnover markers and bone mineral density (BMD). On the other hand, alkaline supplement intervention significantly reduced NAE (SMD = -1.29, P < 0.00001), urinary calcium excretion (SMD = -0.44, P = 0.007), bone resorption marker aminoterminal cross-linking telopeptide (NTX; SMD = -0.29, P = 0.003), and bone formation marker osteocalcin (OC; SMD = -0.23, P = 0.02), but did not affect the other bone turnover markers. Furthermore, alkaline supplements significantly increased BMD in femoral neck [mean difference (MD) = 1.62, P < 0.00001, I2 = 0%], lumbar spine (MD = 1.66, P < 0.00001, I2 = 87%), and total hip (MD = 0.98, P = 0.02, I2 = 99%). Subsequently, meta-regression analyses identified 1 study that substantially contributed to the high heterogeneity of BMD in the latter 2 sites, but sensitivity analysis suggested that this study did not affect the significant pooled effects. Despite that, the results should be interpreted with caution and need to be further validated by a larger RCT. In summary, through integrating evidence from RCTs, the present meta-analysis initially suggests that alkaline supplements may be beneficial to bone metabolism and acidic diets may not be harmful to bone health. This work may be clinically useful for both clinicians and patients with osteoporosis.

Diet-derived fruit and vegetable metabolites show sex-specific inverse relationships to osteoporosis status

BACKGROUND

The impact of nutrition on the metabolic profile of osteoporosis (OS) is unknown.

OBJECTIVE

Identify biochemical factors driving the association of fruit and vegetable (FV) intakes with OS prevalence using an untargeted metabolomics approach.

DESIGN

Cross-sectional dietary, anthropometric and plasma metabolite data were examined from the Boston Puerto Rican Osteoporosis Study, n = 600 (46-79 yr).

METHODS

Bone mineral density was assessed by DXA. OS was defined by clinical standards. A culturally adapted FFQ assessed usual dietary intake. Principal components analysis (PCA) of 42 FV items created 6 factors. Metabolomic profiles derived from plasma samples were assessed on a commercial platform. Differences in levels of 525 plasma metabolites between disease groups (OS vs no-OS) were compared using logistic regression; and associations with FV intakes by multivariable linear regression, adjusted for covariates. Metabolites significantly associated with OS status or with total FV intake were analyzed for enrichment in various biological pathways using Mbrole 2.0, MetaboAnalyst, and Reactome, using FDR correction of P-values. Correlation coefficients were calculated as Spearman's rho rank correlations, followed by hierarchical clustering of the resulting correlation coefficients using PCA FV factors and sex-specific sets of OS-associated metabolites.

RESULTS

High FV intake was inversely related to OS prevalence (Odds Ratio = 0.73; 95% CI = 0.57, 0.94; P = 0.01). Several biological processes affiliated with the FV-associating metabolites, including caffeine metabolism, carnitines and fatty acids, and glycerophospholipids. Important processes identified with OS-associated metabolites were steroid hormone biosynthesis in women and branched-chain amino acid metabolism in men. Factors derived from PCA were correlated with the OS-associated metabolites, with high intake of dark leafy greens and berries/melons appearing protective in both sexes.

CONCLUSIONS

These data warrant investigation into whether increasing intakes of dark leafy greens, berries and melons causally affect bone turnover and BMD among middle-aged and older adults at risk for osteoporosis via sex-specific metabolic pathways, and how gene-diet interactions alter these sex-specific metabolomic-osteoporosis links. ClinicalTrials.gov Identifier: NCT01231958.

Nutritional Supplements and Skeletal Health

PURPOSE OF REVIEW

Nutrition influences skeletal health throughout the lifespan, from the impact of maternal intakes during development, through the development of peak bone mass, to the rate of bone loss during aging. However, there are limited data available on the effects of nutritional supplements on bone density, let alone fracture risk. This review will assess the current literature, focusing on human studies, and emphasizing nutrients where bone density or fracture data are available.

RECENT FINDINGS

Calcium and vitamin D supplements, in combination, reduce fracture risk, particularly in populations with low intakes. Extensive recent analyses have supported the safety of these interventions at recommended intakes. There is growing evidence that specific isoflavones may improve bone density although fracture data are lacking. Multiple other nutrient supplements may benefit skeletal health, but data are limited. The effect size of nutrient interventions are relatively small, requiring large sample sizes for trials with bone outcomes, may be difficult to blind, and the impact of supplementation may depend on baseline intake. However, nutrition is the only intervention that can be implemented life long and on a population wide basis. Further investigation is needed into the potential benefits of nutritional supplements to determine in which settings supplements may add benefit in addition to dietary intakes.

Analysis of Bone Mineral Profile After Prolonged Every-Other-Day Feeding in C57BL/6J Male and Female Mice

Intermitted fasting or every-other-day feeding (EOD) has many positive effects in rodents and humans. Our goal was to describe how EOD influences bone mineral composition in female and male mice under prolonged EOD feeding. Male and female adult mice were fed EOD for 9 months. After this time, we used a direct method of measurement of mineral components in ashes of long bones (humerus and radius) to estimate the content of calcium (Ca), phosphorus (P), potassium (K), magnesium (Mg), and sodium (Na). We also performed histological analysis of sections of long bones. We found no significant changes in mineral composition between ad libitum and EOD fed males and females. We noted higher Ca and P contents in control males vs. females and lower content of Mg in control males vs. females. We observed the presence of marrow adipose tissue (MAT) in sections of EOD-fed females. EOD without supplementation during feeding days did not increase loss of mineral content of bones in C57BL/6J mice, but the presence of MAT only in EOD females indicates a gender-dependent response to EOD treatment in C57BL/6J mice.

Effects of corn syrup solids containing maltobionic acid (maltobionic acid calcium salt) on bone resorption in healthy Japanese adult women: A randomized double-blind placebo-controlled crossover study

Maltobionic acid is known to have an inhibitory effect on the differentiation of osteoclasts, and it has also been reported in an intervention trial that ingestion of corn syrup solids containing maltobionic acid maintained and increased the bone density of postmenopausal women. However, there is no information on whether maltobionic acid improves bone metabolism in humans. Therefore, we evaluated the influence of corn syrup solids containing maltobionic acid (maltobionic acid calcium salt) on bone resorption markers in healthy Japanese women. Forty-one individuals were selected from 68 participants and assigned to two groups: 21 individuals in the test food antecedent group and 20 individuals in the placebo food antecedent group; individuals in the first group ingested 4 g of corn syrup solids containing maltobionic acid, and subjects in the second group ingested 4 g of placebo (hydrous crystalline maltose and calcium carbonate) for 4 weeks. Bone resorption marker levels (DPD and u-NTx) were evaluated by urinalysis. Forty subjects completed the study, and no adverse events related to the test food were observed. Fourteen subjects were excluded prior to the efficacy analysis because of conflict with the control criteria; the remaining 33 subjects were analyzed. Consumption of corn syrup solids containing maltobionic acid was maintained; DPD and u-NTx values were improved (p < .05). These results indicate that corn syrup solids containing maltobionic acid might contribute to suppress bone resorption and improve bone metabolism in postmenstrual women. (UMIN-CTR ID: UMIN000034257; Foundation: San-ei Sucrochemical Co., Ltd.).

Role of Citrate in Pathophysiology and Medical Management of Bone Diseases

Citrate is an intermediate in the “Tricarboxylic Acid Cycle” and is used by all aerobic organisms to produce usable chemical energy. It is a derivative of citric acid, a weak organic acid which can be introduced with diet since it naturally exists in a variety of fruits and vegetables, and can be consumed as a dietary supplement. The close association between this compound and bone was pointed out for the first time by Dickens in 1941, who showed that approximately 90% of the citrate bulk of the human body resides in mineralised tissues. Since then, the number of published articles has increased exponentially, and considerable progress in understanding how citrate is involved in bone metabolism has been made. This review summarises current knowledge regarding the role of citrate in the pathophysiology and medical management of bone disorders.

Fruit and vegetable intake and bones: A systematic review and meta-analysis

BACKGROUND

Although intake of fruits and vegetables seemed to have a protective effect on bone metabolism, its effect on fractures remains uncertain.

METHODS

A systematic review of randomized controlled trials (RCTs) and cohort studies (PROSPERO: CRD42016041462) was performed. RCTs and cohort studies that evaluated the combined intake of fruits and vegetables in men and women aged over 50 years were included. We considered fractures as a primary outcome measure. Changes in bone markers were considered as secondary outcomes. The search strategy included the following descriptors: fruit, vegetables, vegetable products, bone and bones, bone fractures, postmenopausal osteoporosis, and osteoporosis. PubMed, Embase, and Cochrane Library were the databases used. The appraisal of the studies was performed by two independent reviewers, and discussed and agreed upon by both examiners. The data extracted from the RCTs and cohort studies were summarized separately. The risks of fractures were combined across studies using random models. Bone resorption marker (CTx) was summarized with standardized mean differences. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) method was used to evaluate the strength of recommendations.

RESULTS

Of the 1,192 studies screened, 13 articles were included in the systematic review and 10 were included in the pooled analysis (6 cohort studies and 4 RCTs). The six cohort studies included in the meta-analysis included a population of 225,062. The pooled hazard ratio (HR) (95% confidence interval (CI)) of the hip in five studies was 0.92 (0.87, 0.98). Its heterogeneity was moderate (I2 = 55.7%, p = 0.060), GRADE (⊕⊕⊕O). Two cohort studies evaluated the risk of any fracture; the HR was 0.90 (95% CI: 0.86-0.96), with aheterogeneity of 24.9% (p = 0.249, GRADE (⊕⊕⊕O)). There was no association between the bone resorption marker CTx and 3 months of fruit and vegetable intake evaluated by four RCTs, GRADE (⊕⊕O O).

CONCLUSION

There was an association between the increase of at least one serving of fruits and vegetables per day and decreases in the risk of fractures. The level of evidence for this association is moderate.

The negative effect of unloading exceeds the bone-sparing effect of alkaline supplementation: a bed rest study

Potassium bicarbonate was administrated to an already alkaline diet in seven male subjects during a 21-day bed rest study and was able to decrease bed rest induced increased calcium excretion but failed to prevent bed rest-induced bone resorption.

INTRODUCTION

Supplementation with alkali salts appears to positively influence calcium and bone metabolism and, thus, could be a countermeasure for population groups with an increased risk for bone loss. However, the extent to which alkalization counteracts acid-induced bone resorption or whether it merely has a calcium and bone maintenance effect is still not completely understood. In the present study, we hypothesized that additional alkalization to an already alkaline diet can further counteract bed rest-induced bone loss.

METHODS

Seven healthy male subjects completed two parts of a crossover designed 21-day bed rest study: bed rest only (control) and bed rest supplemented with 90 mmol potassium bicarbonate (KHCO₃) daily.

RESULTS

KHCO₃supplementation during bed rest resulted in a more alkaline status compared to the control intervention, demonstrated by the increase in pH and buffer capacity level (pH p = 0.023, HCO₃p = 0.02, ABE p = 0.03). Urinary calcium excretion was decreased during KHCO₃ supplementation (control 6.05 ± 2.74 mmol/24 h; KHCO₃ 4.87 ± 2.21 mmol/24 h, p = 0.03); whereas, bone formation was not affected by additional alkalization (bAP p = 0.58; PINP p = 0.60). Bone resorption marker UCTX tended to be lower during alkaline supplementation (UCTX p = 0.16).

CONCLUSIONS

The more alkaline acid-base status, achieved by KHCO₃ supplementation, reduced renal calcium excretion during bed rest, but was not able to prevent immobilization-induced bone resorption. However, advantages of alkaline salts on bone metabolism may occur under acidic metabolic conditions or with respect to the positive effect of reduced calcium excretion within a longer time frame.

TRIAL REGISTRATION

Trial number: NCT01509456.

In the absence of specific advice, what do patients eat and avoid? Results from a community based diet study in patients suffering from rheumatoid arthritis (RA) with a focus on potassium

Rheumatoid arthritis (RA) is a painful disabling difficult to treat disease. Clinicians and guidelines invariably focus on drugs. Diet is important but lacks robust data. We carried out a comprehensive analytical study in Indian (Asian) patients.

METHODS

141 consenting symptomatic chronic RA patients [mean age 46 years) center and 165 unrelated healthy control subjects (mean age 36 years) completed a a-priori validated food frequency questionnaire in a cross-sectional non-random design study under the supervision of a nutritionist. All patients were under standard rheumatology care. A 3 day retrospective recall record captured dietary data for all subjects. National Indian guidelines were adopted for diet analytics. Standard statistical analysis was carried out; significant p < 0.05.

RESULTS

Daily diet was found to be significantly deficient in calories and consumption of proteins, calcium and potassium when compared to healthy subjects. It was also inadequate for several nutrients when compacted to recommended daily allowance. The proportion of carbohydrates (65%), proteins (15%) and fat (25%) in daily diet was consistent with Indian standards (healthy). Women patients reported higher deficiency. 44% patients consumed vegetarian diet and showed lesser pain and better function compared to non-vegetarians (not significant). 44% patients reported dietary restriction; higher swollen joint counts in patients following any dietary restriction (p = 0.01) or Ayurveda (ancient Indian medicinal system) advise (p = 0.01) or consuming night shade vegetables (p = 0.002).

CONCLUSION

Dietary inadequacy and in particular for protein and potassium was identified in patients of RA. Any form of dietary restriction did not seem to improve RA. Specific dietary needs of RA patients and in particular impact of potassium deficiency needs further research.

Potassium Citrate Supplementation Decreases the Biochemical Markers of Bone Loss in a Group of Osteopenic Women: The Results of a Randomized, Double-Blind, Placebo-Controlled Pilot Study

The relationship involving acid-base imbalance, mineral metabolism and bone health status has previously been reported but the efficacy of the alkalizing supplementation in targeting acid overload and preventing bone loss has not yet been fully elucidated. In this randomized, double-blind, placebo-controlled study, the hypothesis that potassium citrate (K citrate) modifies bone turnover in women with postmenopausal osteopenia was tested. Three hundred and ten women were screened; 40 women met the inclusion criteria and were randomly assigned to the treatment or the placebo group. They were treated with K citrate (30 mEq day⁻¹) or a placebo in addition to calcium carbonate (500 mg day⁻¹) and vitamin D (400 IU day⁻¹). At baseline and time points of 3 and 6 months, serum indicators of renal function, electrolytes, calciotropic hormones, serum bone turnover markers (BTMs) (tartrate-resistant acid phosphatase 5b (TRACP5b), carboxy-terminal telopeptide of type I collagen (CTX), bone alkaline phosphatase (BAP), procollagen type 1 N terminal propeptide (PINP)), and urine pH, electrolytes, and citrate were measured. The follow-up was completed by 17/20 patients in the “K citrate” group and 18/20 patients in the “placebo” group. At baseline, 90% of the patients exhibited low potassium excretion in 24 h urine samples, and 85% of cases had at least one urine parameter associated with low-grade acidosis (low pH, low citrate excretion). After treatment, CTX and BAP decreased significantly in both groups, but subjects with evidence of low-grade acidosis gained significant benefits from the treatment compared to the placebo. In patients with low 24h-citrate excretion at baseline, a 30% mean decrease in BAP and CTX was observed at 6 months. A significant reduction was also evident when low citrate (BAP: −25%; CTX: −35%) and a low pH (BAP: −25%; CTX: −30%) were found in fasting-morning urine. In conclusion, our results suggested that K citrate supplementation improved the beneficial effects of calcium and vitamin D in osteopenic women with a documented potassium and citrate deficit, and a metabolic profile consistent with low-grade acidosis.

Benefits and safety of dietary protein for bone health-an expert consensus paper endorsed by the European Society for Clinical and Economical Aspects of Osteopororosis, Osteoarthritis, and Musculoskeletal Diseases and by the International Osteoporosis Foundation

A summary of systematic reviews and meta-analyses addressing the benefits and risks of dietary protein intakes for bone health in adults suggests that dietary protein levels even above the current RDA may be beneficial in reducing bone loss and hip fracture risk, provided calcium intakes are adequate. Several systematic reviews and meta-analyses have addressed the benefits and risks of dietary protein intakes for bone health in adults. This narrative review of the literature summarizes and synthesizes recent systematic reviews and meta-analyses and highlights key messages. Adequate supplies of dietary protein are required for optimal bone growth and maintenance of healthy bone. Variation in protein intakes within the "normal" range accounts for 2-4% of BMD variance in adults. In older people with osteoporosis, higher protein intake (≥ 0.8-g/kg body weight/day, i.e., above the current RDA) is associated with higher BMD, a slower rate of bone loss, and reduced risk of hip fracture, provided that dietary calcium intakes are adequate. Intervention with dietary protein supplements attenuate age-related BMD decrease and reduce bone turnover marker levels, together with an increase in IGF-I and a decrease in PTH. There is no evidence that diet-derived acid load is deleterious for bone health. Thus, insufficient dietary protein intakes may be a more severe problem than protein excess in the elderly. Long-term, well-controlled randomized trials are required to further assess the influence of dietary protein intakes on fracture risk.

Depletion and repletion of fruit and vegetable intake alters serum bone turnover markers: a 28-week single-arm experimental feeding intervention

This study was designed to evaluate the effects of elevated fruit and vegetable intake on bone turnover markers. In all, twenty-nine subjects (nine male and twenty female, with a mean age of 32·1 (sem 2·5) years) participated in a 28-week single-arm experimental feeding intervention trial and consumed a prescribed low-fruit and vegetable diet for 6 weeks (depletion-1), a provided high-fruit and vegetable diet for 8 weeks (fruit: 360-560 g; vegetables: 450-705 g), another prescribed low-fruit and vegetable diet for 6 weeks (depletion-2) and then their usual diets for 8 weeks (repletion). Serum bone-related biomarkers were analysed with commercial ELISA kits. Plasma carotenoid levels decreased as a result of the depletion phase and increased with the high-fruit and vegetable diet. Compared with the baseline, depletion-1 resulted in higher serum bone resorption marker C-terminal telopeptide of type 1 collagen (CTX) and lower bone formation marker alkaline phosphatase (BAP) (CTX, 0·68 (sem 0·05) v. 0·97 (sem 0·08) ng/ml and BAP, 10·7 (sem 0·7) v. 9·5 (sem 0·8) µg/l for the baseline and the depletion-1, respectively, P<0·05). High intake of fruit and vegetables decreased serum CTX (P<0·05) to 0·60 (sem 0·04) ng/ml and increased serum BAP to 11·3 (sem 0·7) µg/l (P<0·05), compared with the depletion-1 phase. Serum concentrations of CTX were inversely correlated and those of BAP were positively correlated with blood lycopene. These data show that increased fruit and vegetable consumption at or above federal dietary guidance may be beneficial to bone health.

Acid Balance, Dietary Acid Load, and Bone Effects-A Controversial Subject

Modern Western diets, with higher contents of animal compared to fruits and vegetable products, have a greater content of acid precursors vs. base precursors, which results in a net acid load to the body. To prevent inexorable accumulation of acid in the body and progressively increasing degrees of metabolic acidosis, the body has multiple systems to buffer and titrate acid, including bone which contains large quantities of alkaline salts of calcium. Both in vitro and in vivo studies in animals and humans suggest that bone base helps neutralize part of the dietary net acid load. This raises the question of whether decades of eating a high acid diet might contribute to the loss of bone mass in osteoporosis. If this idea is true, then additional alkali ingestion in the form of net base-producing foods or alkalinizing salts could potentially prevent this acid-related loss of bone. Presently, data exists that support both the proponents as well as the opponents of this hypothesis. Recent literature reviews have tended to support either one side or the other. Assuming that the data cited by both sides is correct, we suggest a way to reconcile the discordant findings. This overview will first discuss dietary acids and bases and the idea of changes in acid balance with increasing age, then review the evidence for and against the usefulness of alkali therapy as a treatment for osteoporosis, and finally suggest a way of reconciling these two opposing points of view.

Association of Urinary Citrate With Acid-Base Status, Bone Resorption, and Calcium Excretion in Older Men and Women

CONTEXT

Elevated urine net acid excretion (NAE), indicative of subclinical metabolic acidosis, has been associated with higher bone turnover. Urine citrate, which is a common clinical measure, changes in response to acid-base status but its association with bone turnover is uncertain.

OBJECTIVE

We evaluated the association between change in urine citrate and change in bone turnover and calcium excretion.

DESIGN, INTERVENTION, AND PARTICIPANTS

A total of 233 healthy men and women ≥60 years old were randomly assigned to 1.0 mmol/kg/d potassium bicarbonate (KHCO3), 1.5 mmol/kg/d KHCO3, or placebo for 84 days.

OUTCOME MEASURES

Urine citrate, NAE, N-telopeptide of collagen type-I (NTX), calcium excretion, and serum amino-terminal propeptide of type 1 procollagen (P1NP) were measured before and after intervention.

RESULTS

Urine citrate increased dose dependently after KHCO3 supplementation (P trend < 0.001). The urine citrate change was significantly inversely associated with P1NP change (P = 0.021) but not with change in NTX (P = 0.051) or calcium excretion (P = 0.652). The NAE change was positively associated with change in NTX and calcium excretion (P ≤ 0.003) but not with change in P1NP (P = 0.051). When the urine citrate change and NAE change were included in the same model, the urine citrate change was not associated with change in NTX, calcium excretion, or serum P1NP (P ≥ 0.086), whereas change in NAE remained associated with change in NTX and calcium excretion (P ≤ 0.003).

CONCLUSION

Urine citrate may not be a suitable alternative to NAE when assessing acid-base status in relation to bone turnover in older adults.

[Dietary acid load: A novel target for the nephrologist?]

The acid production of endogenous origin depends mainly on the metabolism of the food and varies with the nature of these. Of the order of 1mEq/kg/day for contemporary food in industrialized countries, it is reduced by more than one third among vegetarians and close to neutrality among vegans. The dietary acid load is eliminated by the normal kidneys, thus maintaining the acid-base equilibrium. In the setting of CKD, it will overflow the capacities of the nephrons, generating a retention of H+ ions, promoting subclinical acidosis. This tissue retention of H+ ions was confirmed by direct techniques in animal models and indirect techniques in humans. The systemic retention of H+ ions and the accompanying compensatory mechanisms have negative consequences on bone tissue, skeletal muscle, cardiovascular risk and renal function. In the animal, the substitution of casein (acid) by soy (alkaline) prevents metabolic acidosis and slows the progression of renal insufficiency. In man, various prospective studies have confirmed that the risk of renal insufficiency was positively correlated with the dietary acid load. Conversely, bicarbonate supplementation and/or a diet enriched with fruits and vegetables, have a favorable effect on renal insufficiency, including in subjects with normal bicarbonate. These results lead to reconsider the K/DOQI recommendations to correct acidosis when the bicarbonate level falls below 22mEq/L, since tissue retention of H+ ions and its negative consequences appear at higher or even normal levels of bicarbonates.

Nutrition and osteoporosis prevention for the orthopaedic surgeon: A wholefoods approach

Osteoporosis is a prevalent and debilitating condition with no signs of subsiding. Rising numbers of people consuming nutrient-poor diets coupled with ageing populations and sedentary lifestyles appear to be the main drivers behind this.

While the nutrients calcium and vitamin D have received most attention, there is growing evidence that wholefoods and other micronutrients have roles to play in primary and potentially secondary osteoporosis prevention.

Until recently, calcium and vitamin D were regarded as the main nutrients essential to bone health but now there are emerging roles for iron, copper and selenium, among others.

Fruit and vegetables are still not being eaten in adequate amounts and yet contain micronutrients and phytochemicals useful for bone remodelling (bone formation and resorption) and are essential for reducing inflammation and oxidative stress.

There is emerging evidence that dried fruits, such as prunes, provide significant amounts of vitamin K, manganese, boron, copper and potassium which could help to support bone health.

Just 50 g of prunes daily have been found to reduce bone resorption after six months when eaten by osteopaenic, postmenopausal women.

Dairy foods have an important role in bone health. Carbonated drinks should not replace milk in the diet.

A balanced diet containing food groups and nutrients needed for bone health across the whole lifecycle may help to prevent osteoporosis.

Greater efforts are needed to employ preventative strategies which involve dietary and physical activity modifications, if the current situation is to improve.

Cite this article: EFORT Open Rev 2017;2:300-308. DOI: 10.1302/2058-5241.2.160079

Vegetable and Fruit Intake and Fracture-Related Hospitalisations: A Prospective Study of Older Women

The importance of vegetable and fruit intakes for the prevention of fracture in older women is not well understood. Few studies have explored vegetable and fruit intakes separately, or the associations of specific types of vegetables and fruits with fracture hospitalisations. The objective of this study was to examine the associations of vegetable and fruit intakes, separately, and specific types of vegetables and fruits with fracture-related hospitalisations in a prospective cohort of women aged ≥70 years. Vegetable and fruit intakes were assessed at baseline (1998) in 1468 women using a food frequency questionnaire. The incidence of fracture-related hospitalisations over 14.5 years of follow-up was determined using the Hospital Morbidity Data Collection, linked via the Western Australian Data Linkage System. Fractures were identified in 415 (28.3%) women, of which 158 (10.8%) were hip fractures. Higher intakes of vegetables, but not fruits, were associated with lower fracture incidence. In multivariable-adjusted models for vegetable types, cruciferous and allium vegetables were inversely associated with all fractures, with a hazard ratio (HR) (95% confidence interval) of 0.72 (0.54, 0.95) and 0.66 (0.49, 0.88), respectively, for the highest vs. lowest quartiles. Increasing vegetable intake, with an emphasis on cruciferous and allium vegetables, may prevent fractures in older postmenopausal women.

The association between urinary sodium to potassium ratio and bone density in middle-aged Chinese adults

The joint effect of sodium and potassium on bone health remains uncertain. We examined the associations between urinary excretion of sodium, potassium, and their ratio and bone mineral density (BMD), and reported an inverse association between urinary sodium-to-potassium ratio and BMD in women, but not in men.

INTRODUCTION

Several studies have suggested that a higher sodium or lower potassium intake is associated with poor bone health. However, few studies have examined their joint effects. We examined the associations of urinary excretion of sodium, potassium, and the sodium-to-potassium ratio with BMD in Chinese adults.

METHODS

This community-based, cross-sectional study included 2202 women and 1063 men (40-75 years) in Guangzhou, China. The BMD of the whole body, lumbar spine, and hip sites were measured by dual-energy x-ray absorptiometry. The concentrations of sodium, potassium, and creatinine of the fasting morning first-void urine sample were measured, and creatinine-adjusted values were then used for further analyses. General information was collected via face-to-face interviews.

RESULTS

For women, after multivariable adjustment, the urinary sodium-to-potassium ratio was inversely associated with BMD at the whole body, total hip, trochanter, and intertrochanter (all p trend <0.05). The mean BMD differences between extreme quartiles ranged from 1.50 to 2.98 % at these sites (all p < 0.05). Similar, but less significant, associations were observed for urinary sodium/creatinine, for which the only significant difference was found at the trochanter (2.00 %, p = 0.016). We did not find any significant associations of BMD with urinary potassium in women and with urinary sodium/creatinine, potassium/creatinine, or their ratio in men.

CONCLUSION

Our findings suggest that the urinary sodium-to-potassium ratio, but not individual creatinine-adjusted values of sodium or potassium, is a good predictor of BMD in women, but not in men.

Greater Intake of Fruit and Vegetables Is Associated with Greater Bone Mineral Density and Lower Osteoporosis Risk in Middle-Aged and Elderly Adults

Objective

A few studies have suggested that the consumption of fruit and vegetables (FV) may benefit bone health, but limited data are available in Asian subjects. We examined the association between FV intake and bone mineral density (BMD) and osteoporosis in Chinese adults.

Methods

This population-based cross-sectional study involved 2083 women and 1006 men aged 40–75 years in Guangzhou, China. Habitual dietary data was collected from a 79-item food frequency questionnaire by face-to-face interviews. The BMD was measured for the whole body (WB), lumbar spine (LS), total hip (TH) and femur neck (FN) with dual-energy X-ray absorptiometry.

Results

After adjustment for potential covariates, we observed dose-dependent associations between total FV intake and BMD and osteoporosis risk. The mean BMD was higher in tertile 3 vs. tertile 1 by 1.33% (TH) and 1.31% (FN) for FV, and 1.10% (WB), 1.57% (TH), and 2.05% (FN) for fruit (all P-trends < 0.05). Significant beneficial associations with BMD at some sites were also found in most fruit categories but not in total vegetables or their subgroups. The odds ratios (95% confidence interval) of osteoporosis (T-score ≤ −2.5) in tertile 3 (vs. 1) were 0.73 (0.58–0.92), 0.37 (0.22–0.60), and 0.71 (0.52–0.97) for FV; 0.82 (0.66–1.03), 0.48 (0.30–0.77) and 0.89 (0.61–1.12) for fruit; and 0.80 (0.64–1.01), 0.57 (0.35–0.92) and 0.76 (0.55–1.05) for vegetables at the LS, TH, and FN, respectively. The favorable association between FV intake and the occurrence of osteoporosis was evident only in subjects with lower BMI (<24.0 kg/m², P-trends < 0.05).

Conclusions

Greater intake of FV was independently associated with a higher BMD and a lower presence of osteoporosis in middle-aged and elderly Chinese subjects with lower BMI. Fruit tended to have more contribution to the favorable association than vegetables.

Nutritional Aspects of Bone Health and Fracture Healing

INTRODUCTION

Fractures are quite common, especially among the elderly. However, they can increase in prevalence in younger ages too if the bone health is not good. This may happen as a result of bad nutrition.

METHODS

A customized, retrospective review of available literature was performed using the following keywords: bone health, nutrition, and fractures.

RESULTS

Insufficient intake of certain vitamins, particularly A and D, and other nutrients, such as calcium, may affect bone health or even the time and degree of bone healing in case of fracture. The importance of different nutrients, both dietary and found in food supplements, is discussed concerning bone health and fracture healing.

CONCLUSION

A healthy diet with adequate amounts of both macro- and micronutrients is essential, for both decreasing fracture risk and enhancing the healing process after fracture.

Food groups associated with measured net acid excretion in community-dwelling older adults

Background

Acid-producing diets have been associated with adverse health conditions. Dietary acid load can be estimated from dietary intake data, but the available methods require a full dietary assessment. We sought to identify a simpler means to estimate 24-hour urinary net acid excretion (NAE), a robust measure of net endogenous acid production, using self-reported intakes of fruits, vegetables (acid-neutralizing foods), grain and/or protein (acid-producing foods)acquired by two different methods in community-dwelling older adults. Identifying food groups associated with NAE using a method not requiring a full diet assessment could have a broad clinical application.

Methods

Fruit, vegetable, protein, and grain servings/day were estimated with a widely-used food frequency questionnaire (study A, n=162, 63±8 years). Differences in their intakes across NAE categories (<5, ≥5to <15, ≥15to <50, ≥50 milliequivalents (mEq)/day) were analyzed using analysis of variance. The findings were verified in a second study which estimated dietary intakes using a more detailed record-assisted 24- hour recall (study B, n=232, 67±6 years).

Results

Fruit intake was significantly associated with NAE in both studies. In study A, fruit intake was 9% lower with each categorical NAE increase (unstandardized beta=-0.21,p=0.01) and 7% lower with each categorical NAE increase in study B (unstandardized beta=-0.18;p=0.02). Grain intake was positively associated with NAE in study B only (unstandardized beta=+0.14;p=0.01). Vegetable and protein intake were not associated with NAE in either study.

Conclusion

The inverse association between fruit intake and NAE suggests low self-reported fruit intake may be an indicator of acid-producing diets in older adults.

Etiological factors associated with chronic suppurative otitis media in a population of Han adults in China

OBJECTIVE

Risk factors for chronic suppurative otitis media (CSOM) were not clearly established. The study was to investigate the etiological factors for CSOM from a population of Han adults in China.

METHODS

A case-control study was conducted at Second Affiliated Hospital of Xi'an Jiaotong University, School of Medicine in China. A total of 416 individuals participated in this study, which included 206 cases and 210 controls.

RESULTS

Multivariate logistic regression analysis revealed male (OR = 0.42; 95% CI: 0.21-0.83), BMI increasing (OR = 0.85; 95% CI: 0.77-0.93), URTI (OR = 152.85; 95% CI: 34.11-684.93), smoke/passive smoke (OR = 7.11; 95% CI: 3.36-15.07), residential location (urban area) (OR = 0.27; 95% CI: 0.13-0.56), serum calcium increasing (OR = 0.09; 95% CI: 0.01-0.71) were prime risk factors for CSOM. Univariate analysis revealed that low socioeconomic status (OR= 2.33; 95% CI: 1.57-3.45) and hepatitis B (OR = 4.90; 95% CI: 1.82-13.21) were risk factors together with the above variables.

CONCLUSION

This study has identified several variables as risk factors for CSOM, suggesting better healthcare, living condition, as well as better nutrition might decrease the development of CSOM. Further studies are necessary to assess the outcome of CSOM after interventions in the etiological factors.

Food fortification for bone health in adulthood: a scoping review

Food fortification can deliver essential micronutrients to large population segments without modifications in consumption pattern, suggesting that fortified foods may be formulated for populations at risk for fragility fractures. This scoping review determined the extent to which randomized controlled studies have been carried out to test the impact of fortified foods on bone outcomes, searching PubMed for all studies using the terms 'fortified AND bone', and 'fortification AND bone'. Studies were restricted to English language, published between 1996 and June 2015. From 360 articles, 24 studies met the following criteria: human study in adults ⩾18 years (excluding pregnancy or lactation); original study of a fortified food over time, with specific bone outcomes measured pre- and post intervention. Six studies involved adults <50 years; 18 involved adults ⩾50 years. Singly or in combination, 17 studies included calcium and 16 included vitamin D. There were 1 or 2 studies involving either vitamin K, magnesium, iron, zinc, B-vitamins, inulin or isoflavones. For adults <50 years, the four studies involving calcium or vitamin D showed a beneficial effect on bone remodeling. For adults ⩾50 years, n=14 provided calcium and/or vitamin D, and there was a significant bone turnover reduction. No consistent effects were reported in studies in which addition of vitamin K, folic acid or isoflavone was assessed. Results from this scoping review indicate that up to now most studies of fortification with bone health have evaluated calcium and/or vitamin D and that these nutrients show beneficial effects on bone remodeling.

Dietary patterns are associated with bone mineral density in an urban Mexican adult population

Several types of nutrients and foods affect bone mineral density (BMD). However, these nutrients occur together in food groups and dietary patterns, and the overall effects of dietary patterns are not yet well known.

INTRODUCTION

We evaluated the associations between dietary patterns and BMD among adults participating in the Health Workers Cohort Study.

METHODS

In a cross-sectional analysis, we examined 6915 Mexican adults aged 20-80 years. All participants completed a validated self-administered food frequency questionnaire (FFQ) and had total, hip, and spine BMD measurements assessed by dual-energy X-ray absorptiometry (DXA). The FFQ included 116 foods, which were grouped into 22 categories and entered into a factor analysis to derive dietary patterns.

RESULTS

Three dietary patterns emerged-a Prudent, a Refined foods, and a Dairy and fish pattern. After adjustment for potential confounders, those in the highest quintile of the Prudent pattern had lower odds (OR) of low spine BMD (OR = 0.80; 95 % CI 0.68, 0.94; P for trend = 0.031) compared to those in the lowest quintile. In contrast, participants in the highest quintile of the Refined foods pattern had greater odds of low total BMD (OR = 1.74; 95 % CI 1.10, 2.76; P for trend = 0.016) than those in the lowest quintile. Finally, participants in the highest quintile of the Dairy and fish dietary pattern had significantly lower likelihood of having low BMD.

CONCLUSION

This study identified specific dietary patterns associated with BMD among a Mexican adult population and highlights the importance of promoting food-based prevention strategies for maintaining bone health.

Diet-induced acidosis and alkali supplementation

Western diet, high in protein-rich foods and poor in vegetables, is likely to be responsible for the development of a moderate acid excess leading to metabolism deregulation and the onset or worsening of chronic disturbances. Available findings seem to suggest that diets with high protein/vegetables ratio are likely to induce the development of calcium lithiasis, especially in predisposed subjects. Moreover, some evidence supports the hypothesis of bone metabolism worsening and enhanced bone loss following acid-genic diet consumption although available literature seems to lack direct and conclusive evidence demonstrating pathological bone loss. According to other evidences, diet-induced acidosis is likely to induce or accelerate muscle wasting or sarcopenia, especially among elderlies. Furthermore, recent epidemiological findings highlight a specific role of dietary acid load in glucose metabolism deregulation and insulin resistance. The aim of this review is to investigate the role of acid-genic diets in the development of the mentioned metabolic disorders focusing on the possible clinical improvements exerted by alkali supplementation.

Potassium Bicarbonate Supplementation Lowers Bone Turnover and Calcium Excretion in Older Men and Women: A Randomized Dose-Finding Trial

The acid load accompanying modern diets may have adverse effects on bone and muscle metabolism. Treatment with alkaline salts of potassium can neutralize the acid load, but the optimal amount of alkali is not established. Our objective was to determine the effectiveness of two doses of potassium bicarbonate (KHCO3 ) compared with placebo on biochemical markers of bone turnover, and calcium and nitrogen (N) excretion. In this double-blind, randomized, placebo-controlled study, 244 men and women age 50 years and older were randomized to placebo or 1 mmol/kg or 1.5 mmol/kg of KHCO3 daily for 3 months; 233 completed the study. The primary outcomes were changes in 24-hour urinary N-telopeptide (NTX) and N; changes in these measures were compared across the treatment groups. Exploratory outcomes included 24-hour urinary calcium excretion, serum amino-terminal propeptide of type I procollagen (P1NP), and muscle strength and function assessments. The median administered doses in the low-dose and high-dose groups were 81 mmol/day and 122 mmol/day, respectively. When compared with placebo, urinary NTX declined significantly in the low-dose group (p = 0.012, after adjustment for baseline NTX, gender, and change in urine creatinine) and serum P1NP declined significantly in the low-dose group (p = 0.004, adjusted for baseline P1NP and gender). Urinary calcium declined significantly in both KHCO3 groups versus placebo (p < 0.001, adjusted for baseline urinary calcium, gender, and changes in urine creatinine and calcium intake). There was no significant effect of either dose of KHCO3 on urinary N excretion or on the physical strength and function measures. KHCO3 has favorable effects on bone turnover and calcium excretion and the lower dose appears to be the more effective dose. Long-term trials to assess the effect of alkali on bone mass and fracture risk are needed.

Bone mineral density and diet of teachers of College of Home Economics at Lahore

OBJECTIVE

To evaluate the Bone Mineral Density (BMD) and diet of teachers of a Govt. College of Home Economics in Lahore.

METHODS

It was survey research. Purposive sampling technique was adopted for the selection of 50 teachers from Govt. College of Home Economics of age group 30 - 60 years.

RESULTS

About 46% of the subjects had BMD ratio in between -2.58 to -4.0 (Osteoporotic category). The root cause of low BMD ratio was not really age related but in majority of the sample it was due to sedentary life style and lack of awareness about the importance of exercise in relation to bone health.

CONCLUSION

The total mineral and vitamin intake required for bone health (calcium, magnesium, phosphorus & vitamin D) was below the recommended, among majority of the sample.

Effects of thirty elements on bone metabolism

The human skeleton, made of 206 bones, plays vital roles including supporting the body, protecting organs, enabling movement, and storing minerals. Bones are made of organic structures, intimately connected with an inorganic matrix produced by bone cells. Many elements are ubiquitous in our environment, and many impact bone metabolism. Most elements have antagonistic actions depending on concentration. Indeed, some elements are essential, others are deleterious, and many can be both. Several pathways mediate effects of element deficiencies or excesses on bone metabolism. This paper aims to identify all elements that impact bone health and explore the mechanisms by which they act. To date, this is the first time that the effects of thirty minerals on bone metabolism have been summarized.

Dietary Approaches for Bone Health: Lessons from the Framingham Osteoporosis Study

Osteoporosis is characterized by systemic impairment of bone mass, strength, and microarchitecture, resulting in increased risk for fragility fracture, disability, loss of independence, and even death. Adequate nutrition is important in achieving and maintaining optimal bone mass, as well as preventing this debilitating disease. It is widely accepted that adequate calcium and vitamin D intake are necessary for good bone health; however, nutritional benefits to bone go beyond these two nutrients. This review article will provide updated information on all nutrients and foods now understood to alter bone health. Specifically, this paper will focus on related research from the Framingham Osteoporosis Study, an ancillary study of the Framingham Heart Study, with data on more than 5000 adult men and women.

Comparison of correlates of bone mineral density in individuals adhering to lacto-ovo, vegan, or omnivore diets: a cross-sectional investigation

Vegetarian diets are associated with factors that may not support bone health, such as low body mass and low intakes of protein; yet, these diets are alkaline, a factor that favors bone mineral density (BMD). This study compared the correlates of BMD in young, non-obese adults consuming meat-based (n = 27), lacto-ovo vegetarian (n = 27), or vegan (n = 28) diets for ≥1 year. A 24 h diet recall, whole body DXA scan, 24 h urine specimen, and fasting blood sample were collected from participants. BMD did not differ significantly between groups. Protein intake was reduced ~30% in individuals consuming lacto-ovo and vegan diets as compared to those consuming meat-based diets (68 ± 24, 69 ± 29, and 97 ± 47 g/day respectively, p = 0.006); yet dietary protein was only associated with BMD for those following vegan diets. Urinary pH was more alkaline in the lacto-ovo and vegan groups versus omnivores (6.5 ± 0.4, 6.7 ± 0.4, and 6.2 ± 0.4 respectively, p = 0.003); yet urinary pH was associated with BMD in omnivores only. These data suggest that plant-based diets are not detrimental to bone in young adults. Moreover, diet prescriptions for bone health may vary among diet groups: increased fruit and vegetable intake for individuals with high meat intakes and increased plant protein intake for individuals who follow a vegetarian diet plan.