Intake of fruit and vegetables: implications for bone health

Anti-Obesity and Anti-Inflammatory Synergistic Effects of Green Tea Catechins and Citrus β-Cryptoxanthin Ingestion in Obese Mice

Chronic obesity causes various diseases, leading to an urgent need for its treatment and prevention. Using monosodium-glutamate-induced obesity mice, the present study investigated the synergistic obesity-reducing effects of tea catechins and the antioxidant β-cryptoxanthin present in mandarin oranges. The results show that the obese mice that ingested both tea catechin and β-cryptoxanthin for 4 weeks had a significantly decreased body weight, with no difference in body weight compared with control mice. Moreover, the blood biochemical test results were normal, and the body fat percentage was significantly decreased according to the histopathological analysis. Additionally, the abundance of M1 macrophages, which release pro-inflammatories, was significantly reduced in adipose tissue. Indeed, a significant decrease was detected in M1-macrophage-secreted tumor necrosis factor-alpha levels. Meanwhile, M2 macrophage levels were recovered, and adiponectin, which is released from adipocytes and involved in suppressing metabolic syndrome, was increased. Collectively, these results suggest that the combination of tea catechins and antioxidant foods can alleviate chronic obesity, indicating that a combination of various ingredients in foods might contribute to reducing chronic obesity.

Association of plant-based dietary patterns with the risk of osteoporosis in community-dwelling adults over 60 years: a cross-sectional study

Plant foods are rich in many important micronutrients that are beneficial for bone health. This cross-sectional study of 9613 community-dwelling older adults found that more consumption of healthy plant foods and less consumption of animal foods and unhealthy plant foods were associated with a lower risk of osteoporosis.

INTRODUCTION

Osteoporosis,a common chronic disease in older adults, threatens their health. Many nutrients in plant foods are important for preventing osteoporosis. However, the relationship between plant-based dietary patterns and osteoporosis remains unclear. This study aimed to investigate the cross-sectional association between plant-based dietary patterns and osteoporosis in older adults.

METHODS

This study was conducted among 9613 community-dwelling older adults in Liaoning Province, China. The effective food frequency questionnaire (FFQ) and plant-based diet index (PDI) were used to evaluate compliance with plant-based dietary patterns. Osteoporosis was defined based on heel ultrasound. We analyzed the association between healthy plant-based diet index (HPDI) and unhealthful plant-based diet index (UPDI) and the risk of osteoporosis.

RESULTS

A higher PDI was associated with higher bone mineral density (BMD) in older adults. In logistic regression models, the highest quartile of PDI and HPDI had a significantly lower risk of osteoporosis than the lowest quartile, whereas UPDI in the highest quartile was associated with a higher risk of osteoporosis. There was a dose-response relationship between the three indices and the risk of osteoporosis. Subgroup analysis revealed differences in the relationship between HPDI and the risk of osteoporosis according to gender and age.

CONCLUSIONS

Older adults, especially women, consume more healthy plant foods and reduce the consumption of animal foods and unhealthy plant foods, which was associated with a lower risk of osteoporosis.

Better Adherence to the Taiwan Daily Food Guide is Associated with a Reduced Risk of Osteoporosis: A Population-Based Study in Taiwan

INTRODUCTION

We conducted a study to examine whether adherence to the Taiwan Daily Food Guide was associated with bone mineral density (BMD).

METHODS

A population-based cross-sectional study was conducted utilizing data from the Nutrition and Health Survey in Taiwan (NAHSIT) 2013-2016. A total of seven BMD sites were evaluated, including the head, arms, legs, trunk, ribs, pelvis, and spine BMD. Besides, we further examined the association between the Daily Food Guide adherence score and osteoporosis (T-score of ≤ -2.5 standard deviation (SD) of a measured total BMD). A validated food-frequency questionnaire (FFQ) was used for dietary assessment.

RESULTS

We included a total of 555 participants with osteoporosis and 1977 without osteoporosis in the final analysis. We found negative associations between levels of adherence to the Daily Food Guide and the risk of osteoporosis. The odds ratio (OR) for participants in the highest quartile of the adherence level was 0.61 (95% CI = 0.42-0.88), compared with those in the lowest quartile. When participants had total servings of six food groups higher than the recommendation, the protective effect still existed (OR = 0.59, 95% CI = 0.42-0.84).

CONCLUSION

Better adherence to the Taiwan Daily Food Guide is associated with a lower risk of osteoporosis.

High bone mass in mice can be linked to lower osteoclast formation, resorptive capacity, and restricted in vitro sensitivity to inhibition by stable sulforaphane

Mouse strains can have divergent basal bone mass, yet this phenotype is seldom reflected in the design of studies seeking to identify new modulators of bone resorption by osteoclasts. Sulforaphane exerts inhibitory effects on in vitro osteoclastogenesis in cells from C57BL/6 mice. Here, we explore whether a divergent basal bone mass in different mouse strains is linked both to in vitro osteoclastogenic potential and to SFX-01 sensitivity. Accordingly, osteoclasts isolated from the bone marrow (BM) of C57BL/6, STR/Ort and CBA mice with low, high, and intermediate bone mass, respectively, were cultured under conditions to promote osteoclast differentiation and resorption; they were also treated with chemically stabilised sulforaphane (SFX-01) and respective sensitivity to inhibition evaluated by counting osteoclast number/resorption activity on dentine discs. We observed that osteoclastogenesis exhibited different macrophage colony-stimulating factor/receptor activator of nuclear factor kappa-Β ligand sensitivity in these mouse strains, with cells from C57BL/6 and CBA generating higher osteoclast numbers than STR/Ort; the latter formed only half as many mature osteoclasts. We found that 100 nM SFX-01 exerted a potent and significant reduction in osteoclast number and resorptive activity in cells derived from C57BL/6 mice. In contrast, 10-fold higher SFX-01 concentrations were required for similar inhibition in CBA-derived cells and, strikingly, a further 2.5-fold greater concentration was required for significant restriction of osteoclast formation/function in STR/Ort. These data are consistent with the notion that the BM osteoclast precursor population contributes to the relative differences in mouse bone mass and that mice with higher bone mass exhibit lower in vitro osteoclastogenic potential as well as reduced sensitivity to inhibition by SFX-01.

The association between dietary sodium intake and osteoporosis

The association of inadequate dietary sodium intake with bone mineral density (BMD) and the risk of osteoporosis is controversial. To find the association between low sodium diet and the risk of incipient osteoporosis, we performed a population-based cross-sectional analysis using Tanaka method for estimation 24-h urinary sodium excretion (e24hUNaETanaka) as a candidate indicator of sodium intake. We identified 3869 participants without osteoporosis and classified them into quartiles according to their value of e24hUNaETanaka. BMD was measured to find participants at risk of osteoporosis. Lower e24hUNaETanaka was related to decreasing BMD of the distal radius. Multiple Cox-proportional hazard models demonstrated that e24hUNaETanaka had an inverse association with the risk of osteoporosis (adjusted HR = 0.859, 95% CI = 0.751-0.982) and survival analysis revealed that the lowest quartile group had poor osteoporosis-free survival (PLog-rank < 0.0001). Furthermore, our restricted cubic spline analysis revealed that the relationship between e24hUNaETanaka and HR of osteoporosis was negative curvilinear in males and postmenopausal females and positive linear in premenopausal females. Our findings suggest that lower sodium intake was a significant predictor of incipient osteoporosis and there was wide variation in this relationship according to sex and female hormone status.

Effects of Dietary Protein Source and Quantity on Bone Morphology and Body Composition Following a High-Protein Weight-Loss Diet in a Rat Model for Postmenopausal Obesity

Higher protein (>30% of total energy, HP)-energy restriction (HP-ER) diets are an effective means to improve body composition and metabolic health. However, weight loss (WL) is associated with bone loss, and the impact of HP-ER diets on bone is mixed and controversial. Recent evidence suggests conflicting outcomes may stem from differences in age, hormonal status, and the predominant source of dietary protein consumed. Therefore, this study investigated the effect of four 12-week energy restriction (ER) diets varying in predominate protein source (beef, milk, soy, casein) and protein quantity (normal protein, NP 15% vs. high, 35%) on bone and body composition outcomes in 32-week-old obese, ovariectomized female rats. Overall, ER decreased body weight, bone quantity (aBMD, aBMC), bone microarchitecture, and body composition parameters. WL was greater with the NP vs. HP-beef and HP-soy diets, and muscle area decreased only with the NP diet. The HP-beef diet exacerbated WL-induced bone loss (increased trabecular separation and endocortical bone formation rates, lower bone retention and trabecular BMC, and more rod-like trabeculae) compared to the HP-soy diet. The HP-milk diet did not augment WL-induced bone loss. Results suggest that specific protein source recommendations may be needed to attenuate the adverse alterations in bone quality following an HP-ER diet in a model of postmenopausal obesity.

The effects of vegetarian diets on bone health: A literature review

In these recent years many people are adopting a vegetarian type diet due to the numerous positive health effects of this regimen such as the reduction of the incidence of many chronic disorders like diabetes, hypertension, obesity and cancer. However this diet is quite restrictive and so it could be possible to have a deficiency in some specific nutrients, increasing the risk of osteoporosis and fractures. Although there are conflicting results on the effects of the vegetarian diet on bone health and fracture incidence, it is always recommendable in vegetarian people to have an adequate intake of calcium and vitamin D, through an increased intake of supplements, natural and fortified foods, an adequate intake of protein, fruit, vegetables, as well as vitamin B12. The aim of this literature review is to revise the actual knowledge of the effect of some nutrients and vegetarian diets on bone health.

Herbal Preparation (Bromelain, Papain, Curcuma, Black Pepper) Enhances Mineralization and Reduces Glucocorticoid-Induced Osteoporosis in Zebrafish

Natural foods with antioxidant properties, such as curcuma, papain, bromelain and black pepper, have been indicated as a potential natural therapeutic approach against osteoporosis. Zebrafish are an excellent animal model to study the effects of herbal preparations on osteogenesis and bone metabolism, both in physiological and in pathological conditions. Our study was aimed at evaluating whether curcuma-bromelain-papain-pepper herbal preparation (CHP) administered in embryos and adult fish is capable of promoting bone wellness in physiological and osteoporotic conditions. The effect of CHP has been studied in embryonic osteogenesis and glucocorticoid-induced osteoporosis (GIOP) in an adult fish model in which drug treatment induces a bone-loss phenotype in adult scales very similar to that which characterizes the bones of human patients. CHP prevented the onset of the osteoporotic phenotype in the scales of GIOP in adult zebrafish, with the osteoblastic and osteoclastic metabolic activity maintaining unaltered. CHP is also able to attenuate an already established GIOP phenotype, even if the alteration is in an advanced phase, partially restoring the normal balance of the bone markers alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP) and stimulating anabolic reparative processes. The results obtained indicated CHP as a potential integrative antioxidant therapy in human bone-loss diseases.

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.

Pregnancy and Lactation in Sprague-Dawley Rats Result in Permanent Reductions of Tibia Trabecular Bone Mineral Density and Structure but Consumption of Red Rooibos Herbal Tea Supports the Partial Recovery

During pregnancy and lactation, maternal bone mineral density (BMD) is reduced as calcium is mobilized to support offspring bone development. In humans, BMD returns to pre-pregnancy levels shortly after delivery, shifting from a high rate of bone resorption during pregnancy and lactation, into a rapid phase of bone formation post-lactation. This rapid change in bone turnover may provide an opportunity to stimulate a greater gain in BMD and stronger trabecular and cortical structure than present pre-pregnancy. Providing polyphenols present in red rooibos herbal tea may promote such an effect. In vitro, red rooibos polyphenols stimulate osteoblast activity, reduce osteoclastic resorption, and increase mineral production. The study objective was to determine if consuming red rooibos from pre-pregnancy through to 4 months post-lactation resulted in a higher BMD and improved trabecular and cortical bone structure in a commonly used rat model. Female Sprague-Dawley rats (n = 42) were randomized to one of the following groups: PREG TEA (pregnant, received supplemental level of red rooibos in water: ~2.6 g /kg body weight/day in water), PREG WATER (pregnant, received water), or NONPREG CON (age-matched, non-pregnant control, received water) from 2 weeks pre-pregnancy (age 8 weeks) through to 4 months post-lactation. Rats were fed AIN-93G (pre-pregnancy through to the end of lactation) and AIN-93M (post-lactation onwards). BMD and trabecular structure (bone volume fraction, trabecular number, trabecular separation) were improved (p < 0.05) by 1- or 2-months post-lactation when comparing PREG TEA to PREG CON, though neither group recovered to the level of NONPREG CON. Cortical outcomes (cortical area fraction, cortical thickness, tissue mineral density) for PREG TEA and PREG CON were reduced (p < 0.05) following lactation but returned to the level of NONPREG CON by 2-months post-lactation, with the exception of cortical thickness. The lack of recovery of BMD and key outcomes of trabecular bone structure was unexpected. While consumption of red rooibos did not result in stronger bone post-lactation, red rooibos did support the partial recovery of trabecular BMD and bone structure following pregnancy and lactation. The findings also provide insight into the timing and dose of polyphenols to study in future interventions.

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.

Effects of vegetarian diet on bone mineral density

Factors, such as hormonal changes in postmenopausal women, natural aging degeneration, race, gender, body size, lifestyle, physical activity, sunlight, dietary intake, medications, or other environmental issues, can affect the rate of bone formation or reabsorption, cause changes in bone mineral content, and influence the development of osteoporosis. Do vegetarian diets adversely affect bone mineral density (BMD)? Among postmenopausal Buddhists, long-term practitioners of vegan vegetarian were found to have a higher risk exceeding the lumbar fracture threshold and a lower level of hip BMD after controlling for other variables. However, results of several prospective longitudinal studies failed to show a harmful effect of vegetarianism on bone health. In the Taiwanese adult population, researchers also did not find that a vegetarian diet significantly affects age-related BMD decline. Due to the various levels of nutrients in the diet (such as protein, alkali, calcium, Vitamin K, and phytoestrogens) and major lifestyle factors (such as smoking and physical exercise), determining the impact of a vegetarian diet on bone health is very complex. Good-quality vegetarian food can provide a healthy foundation for building and maintaining healthy bones and preventing fractures.

Nutrients and Dietary Patterns Related to Osteoporosis

Osteoporosis is a common chronic disease characterized by a decrease in bone mineral density, impaired bone strength, and an increased risk of fragility fractures. Fragility fractures are associated with significant morbidity, mortality and disability and are a major public health problem worldwide. The influence of nutritional factors on the development and progression of this disease can be significant and is not yet well established. Calcium intake and vitamin D status are considered to be essential for bone metabolism homeostasis. However, some recent studies have questioned the usefulness of calcium and vitamin D supplements in decreasing the risk of fractures. The adequate intake of protein, vegetables and other nutrients is also of interest, and recommendations have been established by expert consensus and clinical practice guidelines. It is important to understand the influence of nutrients not only in isolation but also in the context of a dietary pattern, which is a complex mixture of nutrients. In this review, we evaluate the available scientific evidence for the effects of the main dietary patterns on bone health. Although some dietary patterns seem to have beneficial effects, more studies are needed to fully elucidate the true influence of diet on bone fragility.

Liquiritigenin reduces osteoclast activity in zebrafish model of glucocorticoid-induced osteoporosis

Drug and therapies currently used to treat human bone diseases have a lot of severe side effects. Liquiritigenin is a flavonoid extracted from Glycyrrhiza glabra roots which has been reported to have positive effects in vitro on osteoblasts activity and bone mineralization as well as inhibitory effect on osteoclasts differentiation and activity in vitro. The present study was aimed to evaluate the in vivo effects of liquiritigenin on bone structure and metabolism in physiological and pathological conditions using Danio rerio as experimental animal model. Treatments with liquiritigenin were performed on embryos to evaluate the osteogenesis during skeletal development. Other treatments were performed on adult fish affected by glucocorticoid-induced osteoporosis to assay the therapeutic potential of liquiritigenin in the reversion of bone-loss phenotype in scale model. Liquiritigenin treatment of zebrafish embryo significantly enhances the osteogenesis during development in a dose-dependent manner. In addition, liquiritigenin inhibits the formation of the osteoporotic phenotype in adult zebrafish model of glucocorticoid-induced osteoporosis preventing osteoclast activation in scales. Interestingly, liquiritigenin does not counteract the loss of osteoblastic activity in scales. The liquiritigenin exhibits in vivo anti-osteoporotic activity on adult fish scale model. It can be considered a good candidate to develop new drugs against osteoporosis.

Dietary Approaches to Stop Hypertension, Mediterranean, and Alternative Healthy Eating indices are associated with bone health among Puerto Rican adults from the Boston Puerto Rican Osteoporosis Study

BACKGROUND

Conflicting results on associations between dietary quality and bone have been noted across populations, and this has been understudied in Puerto Ricans, a population at higher risk of osteoporosis than previously appreciated.

OBJECTIVE

To compare cross-sectional associations between 3 dietary quality indices [Dietary Approaches to Stop Hypertension (DASH), Alternative Health Eating Index (AHEI-2010), and Mediterranean Diet Score (MeDS)] with bone outcomes.

METHOD

Participants (n = 865-896) from the Boston Puerto Rican Osteoporosis Study (BPROS) with complete bone and dietary data were included. Indices were calculated from validated food frequency data. Bone mineral density (BMD) was measured using DXA. Associations between dietary indices (z-scores) and their individual components with BMD and osteoporosis were tested with ANCOVA and logistic regression, respectively, at the lumbar spine and femoral neck, stratified by male, premenopausal women, and postmenopausal women.

RESULTS

Participants were 59.9 y ± 7.6 y and mostly female (71%). Among postmenopausal women not taking estrogen, DASH (score: 11-38) was associated with higher trochanter (0.026 ± 0.006 g/cm2, P <0.001), femoral neck (0.022 ± 0.006 g/cm2, P <0.001), total hip (0.029 ± 0.006 g/cm2, P <0.001), and lumbar spine BMD (0.025 ± 0.007 g/cm2, P = 0.001). AHEI (score: 25-86) was also associated with spine and all hip sites (P <0.02), whereas MeDS (0-9) was associated only with total hip (P = 0.01) and trochanter BMD (P = 0.007) in postmenopausal women. All indices were associated with a lower likelihood of osteoporosis (OR from 0.54 to 0.75). None of the results were significant for men or premenopausal women.

CONCLUSIONS

Although all appeared protective, DASH was more positively associated with BMD than AHEI or MeDS in postmenopausal women not taking estrogen. Methodological differences across scores suggest that a bone-specific index that builds on existing indices and that can be used to address dietary differences across cultural and ethnic minority populations should be considered.

Polyphenol-Rich Foods and Osteoporosis

BACKGROUND

Osteoporosis is a metabolic disease affecting the bone mineral density and thus compromise the strength of the bones. Disease prevention through diet is the objective of the study and discussion. Among the several nutrients investigated, the intake of phenols seems to influence bone mineral density by acting as free radical scavengers, preventing oxidation-induced damage to bone cells. In addition, the growing understanding of the bone remodelling process supports the theory that inflammation significantly contributes to the etiopathogenesis of osteoporosis.

METHODS

To provide an overview of current evidence on polyphenol-rich foods and osteoporosis prevention we made a comprehensive review of the literature focusing on the state of art of the topic.

RESULTS

Some polyphenol-rich foods, including olive oil, fruit and vegetable, tea and soy, seem to be beneficial for preventing osteoporosis disease and its progression. The mechanism is still partly unknown and may involve different pathways which include inflammation and other disease reactions.

CONCLUSIONS

However, further research is needed to better understand the mechanisms regulating the molecular interaction between osteoporosis incidence and progression and polyphenol-rich foods. The current evidence suggests that dietary intervention with polyphenol rich foods may be useful to prevent incidence and progression of this condition.

Red Rooibos Tea Stimulates Osteoblast Mineralization in a Dose-Dependent Manner

Most studies show a positive association between higher tea intake and bone mineral density (BMD), while associations with fracture are inconclusive. Although a few studies have investigated the potential effects of rooibos tea on the bone cell metabolism, only 1 or 2 doses were tested or specific flavonoids were evaluated in isolation. A dose-response study is needed to comprehensively identify whether a level that modulates bone cell activity is associated with dietary or supplemental levels of red rooibos (RR) tea. We investigated if RR tea stimulates mineralization in a dose-dependent manner. Mineralization was induced in Saos-2 cells in the presence of RR tea (0.1–10 µg/mL of polyphenols) or control (dH2O) for 5 days. Cell activity, mRNA, protein expression and activity of key regulators of mineralization were measured. A positive dose-dependent relationship was observed between RR tea concentration and mineralization accompanied with similar trends in cell activity. With high concentrations of tea, protein expression of enzymes directly regulating mineralization (ALP and NPP1) were unchanged but ALP activity was significantly elevated. Osteopontin (OPN) was significantly downregulated midway through mineralization while sclerostin (SOST) was upregulated in response to higher concentrations of RR tea. In conclusion, RR tea stimulated osteoblast mineralization in a dose-dependent manner and were accompanied with downregulation of OPN, increased ALP activity, and increased cell activity.

Effects of Dietary Protein Quantity on Bone Quantity following Weight Loss: A Systematic Review and Meta-analysis

Research supports the hypothesis that higher total protein intake during weight loss promotes retention of lean soft tissue, but the effect of dietary protein quantity on bone mass, a lean hard tissue, is inconsistent. The purpose of this systematic review and meta-analysis was to assess the effect of dietary protein quantity [higher protein (HP): ≥25% of energy from protein or ≥1.0 g · kg body wt-1 · d-1; normal protein (NP): <25% of energy from protein or <1.0 g · kg body wt-1 · d-1] on changes in bone mineral density (BMD) and content (BMC; total body, lumbar spine, total hip, femoral neck) following a prescribed energy restriction. We hypothesized that an HP diet would attenuate the loss of BMD/BMC following weight loss in comparison to an NP diet. Two researchers systematically and independently screened 2366 publications from PubMed, Cochrane, Scopus, CINAHL, and Web of Science Core Collection and extracted data from 34 qualified publications. Inclusion criteria included the following: 1) healthy subjects ≥19 y; 2) a prescribed energy restriction; 3) measurements of total protein intake, BMD, and BMC; and 4) an intervention duration of ≥3 mo. Data from 10 of the 34 publications with 2 groups of different total protein intakes were extracted and used to conduct a random-effects model meta-analysis. A majority of publications (59%) showed a decrease in bone quantity following active weight loss, regardless of total protein intake. Statistically, the loss of total BMD (P = 0.016; weighted mean difference: +0.006 g/cm2; 95% CI: 0, 0.011 g/cm2) and lumbar spine BMD (P = 0.019; weighted mean difference: +0.017 g/cm2; 95% CI: 0.001, 0.033 g/cm2) was attenuated with an HP versus an NP weight-loss diet. However, the clinical significance is questionable given the modest weighted mean difference and study duration. Higher total protein intake does not exacerbate but may attenuate the loss of bone quantity following weight loss.

Dietary Patterns in Relation to Low Bone Mineral Density and Fracture Risk: A Systematic Review and Meta-Analysis

Low bone mineral density (BMD) and osteoporosis-related fractures constitute a considerable public health burden. Several studies have demonstrated the association between diet and bone health. We performed a systematic review to provide an estimate of the association between different dietary patterns defined through the use of a posteriori methods and fracture or low BMD risk. A literature search on PubMed, Web of Science, and Scopus databases, up to March 2018, was performed to identify all eligible case-control, prospective, or cross-sectional studies involving subjects of both sexes and any age. Random-effects models were used. Heterogeneity and publication bias were evaluated. Stratified analyses were conducted on study characteristics. The meta-analysis includes 20 studies and identifies 3 prevalent dietary patterns: "Healthy," "Milk/dairy," and "Meat/Western." From the 10 studies on fracture, adherence to the "Healthy" pattern reduced the risk, particularly in older people (OR: 0.79; 95% CI: 0.66, 0.95; P = 0.011) and in Eastern countries (OR: 0.64; 95% CI: 0.43, 0.97; P = 0.037), whereas the risk increased with the "Meat/Western" pattern, especially for older people (OR: 1.11; 95% CI: 1.04, 1.18, P = 0.001), in those with hip fractures (OR: 1.15; 95% CI: 1.05, 1.25; P = 0.002), and in Western countries (OR: 1.10; 95% CI: 1.07, 1.14; P < 0.0001). Analyses on low BMD showed a reduced risk in the "Healthy" pattern, particularly for younger people (OR: 0.62; 95% CI: 0.44, 0.89; P = 0.009). The "Meat/Western" pattern increased low BMD risk, especially in older people (OR: 1.31; 95% CI: 1.05, 1.64; P = 0.015). The "Milk/dairy" pattern resulted in the strongest reduction in low BMD risk; when stratifying, this effect remained significant (e.g., older women-OR: 0.57; 95% CI: 0.46, 0.70; P < 0.0001). Nutrition is an important modifiable factor affecting bone health. The "Healthy" and "Milk/dairy" patterns are associated with a reduced risk of low BMD and fracture. In contrast, the "Western" pattern is inversely associated.

Knowledge, attitudes, beliefs, and health behaviors of bone health among Caribbean Hispanic/Latino adults

Few studies have examined knowledge and perceptions of osteoporosis among Caribbean Latino adults. Confusion regarding the term osteoporosis was noted. Doctors were viewed as trusted sources of health information, although descriptions of a paradoxical relationship emerged. This study can be used to inform culturally tailored interventions for osteoporosis prevention.

PURPOSE

The overall goal of this study was to assess knowledge, attitudes, and beliefs of bone health and osteoporosis among Caribbean Latino adults aged > 50 years.

METHODS

This triangulated mixed methods study included completion of a quantitative questionnaire and participation in one of four focus groups to obtain information on (1) general health, (2) knowledge about bone health and osteoporosis, (3) sources of information about bone health, and (4) prevention knowledge and personal responsibility. Quantitative data were analyzed using SAS, and qualitative data were analyzed using descriptive and structural coding by two independent research members.

RESULTS

The majority of participants were female (73%), Dominican (84%), and low income (82% < $20,000) with a mean age of 68.4 (± 8.5) years. Most participants had heard of osteoporosis (90%); however, the majority were not able to accurately describe this chronic condition. Health care providers were viewed as most trusted sources of health information, despite feelings of being rushed during their visits, with limited communication about preventative care. Most participants felt that nutrition and exercise were important for overall health.

CONCLUSIONS

Caribbean Hispanic adults in this study reported knowledge of osteoporosis and nutritional factors associated with prevention of this chronic condition. However, qualitatively, there was confusion between osteoporosis and other bone and joint conditions. Culturally specific interventions to promote prevention of osteoporosis are urgently needed for this underserved, high-risk population.

Can increasing the prevalence of vegetable-based diets lower the risk of osteoporosis in postmenopausal subjects? A systematic review with meta-analysis of the literature

OBJECTIVES

Several epidemiological investigations have assessed the association between vegetable-based diet intake (VDI) and risk of osteoporosis in postmenopausal subjects (OPS), but the outcomes have been inconsistent. We performed a review of the updated literature to evaluate this correlation.

METHODS

We searched for relevant studies published in September 2018 or earlier. Two researchers conducted eligibility assessment and data extraction. Discrepancies were resolved through consultation with a third expert. Pooled odds ratios (ORs) were calculated with 95% confidence intervals (CIs).

RESULTS

Ten studies, which included 14,247 subjects, were identified. On comparing the highest category of VDI consumption with the lowest category of VDI consumption, the pooled OR for OPS was 0.73 (95% CI = 0.57-0.95), i.e., participants with a higher intake of vegetables had a 27% (95% CI = 5-43%) lower risk of OPS. Significant benefits were found on subgroup analyses of case-control studies (OR, 0.61 [95% CI, 0.48-0.78]), but not on subgroup analyses of cross-sectional studies (OR, 0.82 [95% CI, 0.57-1.16]). The synthesized effect estimates were in the direction of decreased risk of OPS on subgroup analyses of the femoral region (OR, 0.57, 95% CI = 0.41-0.80) and the lumbar spine (OR = 0.55, 95% CI = 0.38-0.81), but not on subgroup analyses of the calcaneus (OR = 0.85, 95% CI = 0.33-2.16) and the lumbar and/or femoral region (OR = 1.04, 95%CI = 0.79-1.38). Positive results were observed on pooled analyses of the Dual energy X-ray absorptiometry (DEXA) measurement method (OR, 0.72 [95% CI, 0.54-0.95]), but not on pooled analyses of the Standardized Quantitative Ultrasound (QUS) measurement method (OR, 0.85 [95% CI, 0.33-2.16]). This might have resulted from a type II error due to wide confidence intervals and less number of included studies.

CONCLUSION

This meta-analysis seemingly confirms that higher consumption of VDI was associated with a lower risk of OPS. Taken together, these results highlight the need for future high-quality design-based trials on quantified vegetable intake and OPS.

Dietary Patterns, Bone Mineral Density, and Risk of Fractures: A Systematic Review and Meta-Analysis

The aim of this systematic review was to assess the evidence on the relation between dietary patterns, bone mineral density (BMD), and risk of fracture in different age groups. Medline and Embase were searched for articles that identified dietary patterns and related these to BMD or risk of fracture through May 2018. Multivariable adjusted odds ratios (ORs) and 95% confidence intervals (95%CI) comparing the lowest and highest categories of dietary pattern were combined by using a random effects meta-analysis. In total, 31 studies were selected for review, including 18 cohorts, 1 case-control, and 12 cross-sectional studies, in the meta-analysis of Prudent/healthy and Western/unhealthy dietary pattern, BMD, and risk of fracture. There was evidence of a lower risk of fracture when intakes in the highest categories were compared with the lowest categories of Prudent/healthy dietary pattern (OR = 0.81; 95%CI: 0.69, 0.95; p = 0.01). In contrast, when intakes in the highest categories were compared with the lowest categories of Western/unhealthy dietary pattern, a greater risk of fracture (OR = 1.10; 95%CI: 1.02, 1.19; p = 0.01) was observed among men. The present systematic review and meta-analysis provides evidence of an inverse association between a Prudent/healthy dietary pattern and risk of low BMD and a positive relation between Western/unhealthy dietary pattern and risk of low BMD.

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.

Vegetarian-style dietary pattern during adolescence has long-term positive impact on bone from adolescence to young adulthood: a longitudinal study

BACKGROUND

The amount of bone accrued during adolescence is an important determinant of later osteoporosis risk. Little is known about the influence of dietary patterns (DPs) on the bone during adolescence and their potential long-term implications into adulthood. We examined the role of adolescent DPs on adolescent and young adult bone and change in DPs from adolescence to young adulthood.

METHODS

We recruited participants from the Saskatchewan Pediatric Bone Mineral Accrual Study (1991-2011). Data from 125 participants (53 females) for adolescent analysis (age 12.7 ± 2 years) and 115 participants (51 females) for adult analysis (age 28.2 ± 3 years) were included. Bone mineral content (BMC) and areal bone mineral density (aBMD) of total body (TB), femoral neck (FN) and lumbar spine (LS) were measured using dual-energy X-ray absorptiometry. Adolescent dietary intake data from multiple 24-h recalls were summarized into 25 food group intakes and were used in the principal component analysis to derive DPs during adolescence. Associations between adolescent DPs and adolescent or adult BMC/BMD were analyzed using multiple linear regression and multivariate analysis of covariance while adjusting for sex, age, the age of peak height velocity, height, weight, physical activity and total energy intake. Generalized estimating equations were used for tracking DPs.

RESULTS

We derived five DPs including "Vegetarian-style", "Western-like", "High-fat, high-protein", "Mixed" and "Snack" DPs. The "Vegetarian-style" DP was a positive independent predictor of adolescent TBBMC, and adult TBBMC, TBaBMD (P < 0.05). Mean adolescent TBaBMD and young adult TBBMC, TBaBMD, FNBMC and FNaBMD were 5%, 8.5%, 6%, 10.6% and 9% higher, respectively, in third quartile of "Vegetarian-style" DP compared to first quartile (P < 0.05). We found a moderate tracking (0.47-0.63, P < 0.001) in DP scores at individual levels from adolescence to adulthood. There were an upward trend in adherence to "Vegetarian-style" DP and an downward trend in adherence to "High-fat, high-protein" DP from adolescence to young adulthood (P < 0.01).

CONCLUSION

A "Vegetarian-style" DP rich in dark green vegetables, eggs, non-refined grains, 100% fruit juice, legumes/nuts/seeds, added fats, fruits and low-fat milk during adolescence is positively associated with bone health.

High dietary salt intake correlates with modulated Th17-Treg cell balance resulting in enhanced bone loss and impaired bone-microarchitecture in male mice

Osteoporosis is associated with reduced density and quality of bone leading to weakened skeleton thereby increasing the risk of fractures responsible for increased morbidity and mortality. Due to preference for western food style the consumption of salt intake in our diets has increased many folds. High dietary salt intake has recently been linked with induction of Th17 cells along with impairment of Treg cells. Also, Th17 cells have been one of major players in the pathophysiology of various bone pathologies including osteoporosis. We thus hypothesized that high salt diet (HSD) intake would lead to enhanced bone loss by modulating Th17-Treg cell balance. In the present study, we report for the first time that HSD intake in male mice impairs both trabecular and cortical bone microarchitecture along with decreasing the mineral density and heterogeneity of bones. The HSD modulates host immune system and skews Treg-Th17 balance by promoting osteoclastogenic Th17 cells and inhibiting development of anti-osteoclastogenic Treg cells in mice. HSD also enhanced expression of proinflammatory cytokines (IL-6, TNF-α, RANKL and IL-17) and decreased the expression of anti-inflammatory cytokines (IL-10, IFN-γ). Taken together the present study for the first time establishes a strong correlation between high dietary salt intake and bone health via interplay between Th17-Treg cells.

Fruit and vegetable consumption and the risk of postmenopausal osteoporosis: a meta-analysis of observational studies

The association of the consumption of fruit and vegetables (FV) and the risk of postmenopausal osteoporosis (PMOP) has been a controversial subject.

Biocompatibility of Four Common Orthopedic Biomaterials Following a High-Salt Diet: An In Vivo Study

Nowadays, salt consumption appears to be drastically above the recommended level in industrialized countries. The health consequences of this overconsumption are heavy since high-salt intake induces cardiovascular disease, kidney dysfunction, and stroke. Moreover, harmful interaction may also occur with orthopaedic devices because overconsumption of salt reinforces the corrosive aspect of biological tissues and favors bone resorption process. In the present study, we aimed to assess the in vivo effect of three weeks of a high-salt diet, associated (or not) with two weeks of the neuro-myoelectrostimulation (NMES) rehabilitation program on the biocompatibility of four biomaterials used in the manufacture of arthroplasty implants. Thus, two non-metallic (PEEK and Al₂O₃) and two metallic (Ti6Al4V and CrCo) compounds were implanted in the rat tibial crest, and the implant-to-bone adhesion and cell viability of two surrounded muscles, the Flexor Digitorum (FD) and Tibialis Anterior (TA), were assessed at the end of the experiment. Results indicated lower adhesion strength for the PEEK implant compared to other biomaterials. An effect of NMES and a high-salt diet was only identified for Al₂O₃ and Ti6Al4V implants, respectively. Moreover, compared to a normal diet, a high-salt diet induced a higher number of dead cells on both muscles for all biomaterials, which was further increased for PEEK, Al₂O₃, and CrCo materials with NMES application. Finally, except for Ti6Al4V, NMES induced a higher number of dead cells in the directly stimulated muscle (FD) compared to the indirectly stimulated one (TA). This in vivo experiment highlights the potential harmful effect of a high-salt diet for people who have undergone arthroplasty, and a rehabilitation program based on NMES.

High dietary sodium intake is associated with low bone mass in postmenopausal women: Korea National Health and Nutrition Examination Survey, 2008-2011

The present cross-sectional study performed using data from the Korea National Health and Nutrition Examination Survey in 9526 women older than 18 years of age demonstrates that high sodium intake is associated with lower bone mineral density and sodium intake ≥2000 mg/day is a risk factor for osteoporosis in postmenopausal women.

INTRODUCTION

Several studies have reported that large amount of dietary sodium intake is highly associated with elevated urinary calcium. However, the direct effect of excessive dietary sodium intake on bone mass, as a risk factor for osteoporosis, is still a controversial issue. The aim of the present study was to assess the relationship between high intake of sodium and lower bone mass and risk of osteoporosis in adult women.

METHODS

This cross-sectional study was performed using data from the Korea National Health and Nutrition Examination Survey (KNHANES), 2008-2011. Participants (n = 9526 women older than 18 years) were divided into a premenopausal (n = 4793) and postmenopausal (n = 4733) group. Both groups were subdivided into five groups according to quintiles of energy-adjusted sodium intake. Multiple regression analysis was performed to assess relationships between sodium intake and lower bone mass.

RESULTS

Multivariate linear regression analysis showed that high sodium intake was negatively associated with bone mineral content (BMC) and bone mineral density (BMD) in postmenopausal women. After adjusting confounding factors, high sodium intake was negatively associated with BMC and BMD of the lumbar spine in postmenopausal women. Postmenopausal women, whose sodium intake was ≥2000 mg/day (odds ratio 1.284, 95% CI 1.029-1.603, P = 0.027), were at risk of developing osteoporosis after adjustment of confounding variables.

CONCLUSIONS

The present study suggested that high sodium intake could be a potential risk factor for low bone mass after adjusting for confounding factors in postmenopausal women.

Whey Protein Supplementation and Higher Total Protein Intake Do Not Influence Bone Quantity in Overweight and Obese Adults Following a 36-Week Exercise and Diet Intervention

BACKGROUND

Controversy exists concerning the effects of higher total protein intake (TPro) on bone health, which may be associated with reduced bone mineral density (BMD). However, whey protein (WP) may induce bone formation because of its basic component, milk basic protein.

OBJECTIVE

This study assessed the effects of WP supplementation, TPro, and change in TPro (postsupplementation - presupplementation) on BMD and bone mineral content (BMC; total body, lumbar spine, total femur, and femoral neck) in overweight and class I obese middle-aged adults following an exercise intervention.

METHODS

This analysis used data from a double-blind, randomized, placebo-controlled 36-wk WP supplementation trial, wherein participants consumed a 1.7-MJ (400-kcal) supplement (0, 20, 40, or 60 g WP/d) along with their otherwise unrestricted diet while participating in a resistance and aerobic exercise intervention (3 d/wk). TPro was the summation of WP and habitual dietary intakes (4-d food record). Statistical analyses for WP were based on group and bone data [n = 186, 108 women; mean ± SD age: 49 ± 8 y; body mass index (BMI; in kg/m²): 30.1 ± 2.8], whereas TPro was based on dietary and bone data (n = 113, 70 women; age 50 ± 8 y; BMI 30.1 ± 2.9).

RESULTS

WP supplementation, regardless of dose, did not influence BMD or BMC following the intervention. By using a multiple linear regression model, TPro (expressed as g/d or g · kg^-1 · d^-1) and change in TPro (expressed as g/d) were not associated with responses over time in total or regional BMD or BMC. By using a cluster analysis approach [<1.0 (n = 41), 1.0-1.2 (n = 28), and ≥1.2 g · kg^-1 · d^-1 (n = 44)], TPro was also not associated with responses in total or regional BMD or BMC over time.

CONCLUSION

WP supplementation and total dietary protein intake did not negatively or beneficially influence bone quantity in overweight and obese adults during a 9-mo exercise intervention. This trial was registered at clinicaltrials.gov as NCT00812409.

Current Evidence on the Association of Dietary Patterns and Bone Health: A Scoping Review

Nutrition is an important modifiable factor that affects bone health. Diet is a complex mixture of nutrients and foods that correlate or interact with each other. Dietary pattern approaches take into account contributions from various aspects of diet. Findings from dietary pattern studies could complement those from single-nutrient and food studies on bone health. In this study we aimed to conduct a scoping review of the literature that assessed the impact of dietary patterns (derived with the use of both a priori and data-driven approaches) on bone outcomes, including bone mineral status, bone biomarkers, osteoporosis, and fracture risk. We retrieved 49 human studies up to June 2016 from the PubMed, Embase, and CINAHL databases. Most of these studies used a data-driven method, especially factor analysis, to derive dietary patterns. Several studies examined adherence to a variety of the a priori dietary indexes, including the Mediterranean diet score, the Healthy Eating Index (HEI), and the Alternative Healthy Eating Index (AHEI). The bone mineral density (BMD) diet score was developed to measure adherence to a dietary pattern beneficial to bone mineral density. Findings revealed a beneficial impact of higher adherence to a "healthy" dietary pattern derived using a data-driven method, the Mediterranean diet, HEI, AHEI, Dietary Diversity Score, Diet Quality Index-International, BMD Diet Score, Healthy Diet Indicator, and Korean Diet Score, on bone. In contrast, the "Western" dietary pattern and those featuring some aspects of an unhealthy diet were associated inversely with bone health. In both a priori and data-driven dietary pattern studies, a dietary pattern that emphasized the intake of fruit, vegetables, whole grains, poultry and fish, nuts and legumes, and low-fat dairy products and de-emphasized the intake of soft drinks, fried foods, meat and processed products, sweets and desserts, and refined grains showed a beneficial impact on bone health. Overall, adherence to a healthy dietary pattern consisting of the above-mentioned food groups can improve bone mineral status and decrease osteoporosis and fracture risk.

State of the Art Reviews: Relationship Between Diet/ Physical Activity and Health

Obesity and 4 of the leading causes of death—heart disease, cancer, stroke, and type 2 diabetes mellitus—are related to lifestyle. The combination of a healthy weight, prudent diet, and daily physical activity clearly plays a role in primary, secondary, and tertiary prevention of these and other chronic diseases. Because nearly 65% of the adult population is overweight or obese, weight loss and maintenance are central to this review article. Improved lipid profiles, blood pressure, insulin sensitivity, and euglycemia are associated with weight loss or a normal body weight; thus, maintaining a healthy weight is a universal recommendation for health. The methods for improving lifestyle described in the section on obesity include assessing nutritional status and stages of change of the client, setting realistic goals, eating a diet high in fruits and vegetables with low-fat sources of dairy and protein, and achieving appropriate physical activity levels. The importance of physicians discussing weight with clients and vice versa is stressed. The common features of lifestyle-related diseases make them amenable to similar lifestyle interventions.

Protective Efficacy of the Ingestion of Mandarin Orange Containing β-Cryptoxanthin on Lipopolysaccharide-induced Acute Nephritis

β-cryptoxanthin is a common carotenoid pigment found in fruit, especially in Satsuma mandarins and in persimmons. After ingestion, β-cryptoxanthin is distributed to and accumulates in organs, such as the liver, lung, and kidney. Recent studies have reported that because of its antioxidant defense, β-cryptoxanthin performs several important functions in the preservation of human health and in the prevention of several diseases, including cancer and osteoporosis. The present study aims to determine whether β-cryptoxanthin has a protective effect on renal glomeruli during acute nephritis. To develop our acute nephritis mouse model, we induced kidney inflammation in mice using lipopolysaccharide. To analyze pathological changes in the renal glomeruli of these mice, tissue sections of the kidney were analyzed by hematoxylin-eosin and periodic acid-Schiff staining. In mice with acute nephritis, we observed a thickening of the basal membrane in the renal glomeruli. By ultrastructural analysis, abnormalities in the foot cells were also identified. In the β-cryptoxanthin-ingested mice, these pathological changes were decreased. Migration of urinal proteins occurred in mice with acute nephritis, but this was decreased in β-cryptoxanthin-ingested mice, such that it correlated with the blood concentration of β-cryptoxanthin. Furthermore, in β-cryptoxanthin-ingested mice, both the accumulation and activation of inflammatory cells were decreased in the renal glomeruli. These results suggest that β-cryptoxanthin ingestion may produce great improvement in acute nephritis. These findings provide new insights into β-cryptoxanthin and its protective effect, and provide a new target for pharmacological therapy in human disease.

A 7-Year Longitudinal Trial of the Safety and Efficacy of a Vitamin/Mineral Enhanced Plant-Sourced Calcium Supplement

OBJECTIVES

The objective of this study was to examine the safety and efficacy of a vitamin-mineral enhanced plant-sourced calcium AlgaeCal calcium (AC) in female consumers who had taken the supplement from 1 to 7 years.

METHODS

Consumers who had completed at least one dual-energy x-ray absorptiometry (DEXA) bone mineral density (BMD) scan (N = 172) and/or blood chemistry test (N = 30) and purchased AC from 1 to 7 years were contacted and offered complimentary repeat tests. Safety and efficacy were examined by annualized changes in a 45-measurement blood chemistry panel and changes in BMD.

RESULTS

No adverse effects or safety concerns were found in any of the annualized within-group annualized changes in the 45 blood chemistries or in between-group changes in a similar control group (n = 5070) who completed the same measurements. With regard to BMD, consistent and statistically significant within-group increases were found for the 7-year study period and when compared to expected BMD changes in 3 large databases or the combination (N = 25,885) of the 3 databases. Data from this study suggest that AC supplement was associated with a significant annualized and linear increase in BMD of 1.04% per year, 7.3% over the 7-year study period. These results stand in marked contrast to normative or expected changes of -0.4%/y from 3 different databases or in a combination of all 3 databases (N = 16,289).

CONCLUSIONS

No evidence was found in cardiovascular risk as measured by adverse changes in blood lipids, nor was any evidence found of a diminished efficacy over the 7-year study period because gains in BMD were consistent and linear over the 7-year study period, averaging 1.04% per year over the 7-year study. The results are also consistent with earlier short-term studies suggesting that this supplement can facilitate significant increases in total body BMD in contrast to studies suggesting that calcium supplements can only slow down age-related declines in BMD.

Increased intake of vegetables, but not fruits, may be associated with reduced risk of hip fracture: A meta-analysis

Association between dietary intake of vegetables and fruits and risk of hip fracture has been reported for many years. However, the findings remain inconclusive. We conducted a meta-analysis to evaluate the relationship between intake of vegetables and fruits, and risk of hip fracture. Literature search for relevant studies was performed on PubMed and Embase databases. Five observational studies were included in the meta-analysis. Summary hazard ratio (HR) with corresponding 95% confidence interval (CI) was calculated from pooled data using the random-effects model irrespective of heterogeneity. Sensitivity and subgroup analysis were performed to explore possible reasons for heterogeneity. The summary HR for hip fracture in relation to high intake vs. low intake of only vegetables, only fruits, and combined intake of fruits and vegetables, was 0.75 (95% CI, 0.61–0.92), 0.87 (95% CI, 0.74–1.04), and 0.79 (95% CI, 0.61–1.03), respectively. Subgroup analyses based on study design, geographical location, number of cases, and gender showed similar results. Increased intake of vegetables, but not fruits, was found to be associated with a lower risk of hip fracture. Large prospective clinical trials with robust methodology are required to confirm our findings.

Association of urinary sodium/creatinine ratio with bone mineral density in postmenopausal women: KNHANES 2008-2011

Accumulating evidence shows that high sodium chloride intake increases urinary calcium excretion and may be a risk factor for osteoporosis. However, the effect of oral sodium chloride intake on bone mineral density (BMD) and risk of osteoporosis has been inadequately researched. The aim of the present study was to determine whether urinary sodium excretion (reflecting oral sodium chloride intake) associates with BMD and prevalence of osteoporosis in postmenopausal women. This cross-sectional study involved a nationally representative sample consisting of 2,779 postmenopausal women who participated in the Korea National Health and Nutritional Examination Surveys in 2008-2011. The association of urinary sodium/creatinine ratio with BMD and other osteoporosis risk factors was assessed. In addition, the prevalence of osteoporosis was assessed in four groups with different urinary sodium/creatinine ratios. Participants with osteoporosis had significantly higher urinary sodium/creatinine ratios than the participants without osteoporosis. After adjusting for multiple confounding factors, urinary sodium/creatinine ratio correlated inversely with lumbar spine BMD (P = 0.001). Similarly, when participants were divided into quartile groups according to urinary sodium/creatinine ratio, the average BMD dropped as the urinary sodium/creatinine ratio increased. Multiple logistic regression analysis revealed that compared to quartile 1, quartile 4 had a significantly increased prevalence of lumbar spine osteoporosis (odds ratios 1.346, P for trend = 0.044). High urinary sodium excretion was significantly associated with low BMD and high prevalence of osteoporosis in lumbar spine. These results suggest that high sodium chloride intake decreases lumbar spine BMD and increases the risk of osteoporosis in postmenopausal women.

Fruit and vegetable intake and risk of hip fracture: a cohort study of Swedish men and women

Dietary guidelines recommend a daily intake of 5 servings of fruits and vegetables. Whether such intakes are associated with a lower risk of hip fracture is at present unclear. The aim of the present study was to investigate the dose-response association between habitual fruit and vegetable intake and hip fracture in a cohort study based on 40,644 men from the Cohort of Swedish Men (COSM) and 34,947 women from the Swedish Mammography Cohort (SMC) (total n = 75,591), free from cardiovascular disease and cancer, who answered lifestyle questionnaires in 1997 (age 45 to 83 years). Intake of fruits and vegetables (servings/day) was assessed by food frequency questionnaire and incident hip fractures were retrieved from the Swedish Patient Register (1998 to 2010). The mean follow-up time was 14.2 years. One-third of the participants reported an intake of fruits and vegetables of >5 servings/day, one-third reported >3 to ≤5 servings/day, 28% reported >1 to ≤3 servings/day, and 6% reported ≤1 serving/day. During 1,037,645 person-years we observed 3644 hip fractures (2266 or 62% in women). The dose-response association was found to be strongly nonlinear (p < 0.001). Men and women with zero consumption had 88% higher rate of hip fracture compared with those consuming 5 servings/day; adjusted hazard ratio (HR) was 1.88 (95% CI, 1.53 to 2.32). The rate was gradually lower with higher intakes; adjusted HR for 1 versus 5 servings/day was 1.35 (95% CI, 1.21 to 1.58). However, more than 5 servings/day did not confer additionally lower HRs (adjusted HR for 8 versus 5 servings/day was 0.96; 95% CI, 0.90 to 1.03). Similar results were observed when men and women were analyzed separately. We conclude that there is a dose-response association between fruit and vegetable intake and hip fracture such that an intake below the recommended five servings/day confers higher rates of hip fracture. Intakes above this recommendation do not seem to further lower the risk.

Increased intake of selected vegetables, herbs and fruit may reduce bone turnover in post-menopausal women

Increased consumption of vegetables/herbs/fruit may reduce bone turnover and urinary calcium loss in post-menopausal women because of increased intake of polyphenols and potassium, but comparative human studies are lacking. The main aim was to compare bone turnover markers and urinary calcium excretion in two randomised groups (n = 50) of healthy post-menopausal women consuming ≥9 servings of different vegetables/herbs/fruit combinations (three months). Group A emphasised a generic range of vegetables/herbs/fruit, whereas Group B emphasised specific vegetables/herbs/fruit with bone resorption-inhibiting properties (Scarborough Fair Diet), with both diets controlled for potential renal acid load (PRAL). Group C consumed their usual diet. Plasma bone markers, urinary electrolytes (24 h) and estimated dietary PRAL were assessed at baseline and 12 weeks. Procollagen type I N propeptide (PINP) decreased (−3.2 μg/L, p < 0.01) in the B group only, as did C-terminal telopeptide of type I collagen (CTX) (−0.065 μg/L, p < 0.01) in women with osteopenia compared to those with normal bone mineral density (BMD) within this group. Intervention Groups A and B had decreased PRAL, increased urine pH and significantly decreased urinary calcium loss. Urinary potassium increased in all groups, reflecting a dietary change. In conclusion, Group B demonstrated positive changes in both turnover markers and calcium conservation.

Health gain by salt reduction in europe: a modelling study

Excessive salt intake is associated with hypertension and cardiovascular diseases. Salt intake exceeds the World Health Organization population nutrition goal of 5 grams per day in the European region. We assessed the health impact of salt reduction in nine European countries (Finland, France, Ireland, Italy, Netherlands, Poland, Spain, Sweden and United Kingdom). Through literature research we obtained current salt intake and systolic blood pressure levels of the nine countries. The population health modeling tool DYNAMO-HIA including country-specific disease data was used to predict the changes in prevalence of ischemic heart disease and stroke for each country estimating the effect of salt reduction through its effect on blood pressure levels. A 30% salt reduction would reduce the prevalence of stroke by 6.4% in Finland to 13.5% in Poland. Ischemic heart disease would be decreased by 4.1% in Finland to 8.9% in Poland. When salt intake is reduced to the WHO population nutrient goal, it would reduce the prevalence of stroke from 10.1% in Finland to 23.1% in Poland. Ischemic heart disease would decrease by 6.6% in Finland to 15.5% in Poland. The number of postponed deaths would be 102,100 (0.9%) in France, and 191,300 (2.3%) in Poland. A reduction of salt intake to 5 grams per day is expected to substantially reduce the burden of cardiovascular disease and mortality in several European countries.

Dietary acid load, kidney function, osteoporosis, and risk of fractures in elderly men and women

SUMMARY

Because kidney dysfunction reduces the ability to excrete dietary acid excess, we hypothesized that underlying kidney function may have confounded the mixed studies linking dietary acid load with the risk of osteoporosis and fractures in the community. In a relatively large survey of elderly men and women, we report that dietary acid load did neither associate with DEXA-estimated bone mineral density nor with fracture risk. Underlying kidney function did not modify these null findings. Our results do not support the dietary acid-base hypothesis of bone loss.

INTRODUCTION

Impaired renal function reduces the ability to excrete dietary acid excess. We here investigate the association between dietary acid load and bone mineral density (BMD), osteoporosis, and fracture risk by renal function status.

METHODS

An observational study was conducted in 861 community-dwelling 70-year-old men and women (49% men) with complete dietary data from the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS). The exposure was dietary acid load as estimated from 7-day food records by the net endogenous acid production (NEAP) and potential renal acid load (PRAL) algorithms. Renal function assessed by cystatin C estimated glomerular filtration rate was reduced in 21% of the individuals. Study outcomes were BMD and osteoporosis state (assessed by DEXA) and time to fracture (median follow-up of 9.2 years).

RESULTS

In cross-section, dietary acid load had no significant associations with BMD or with the diagnosis of osteoporosis. During follow-up, 131 fractures were validated. Neither NEAP (adjusted hazard ratios (HR) (95% confidence interval (CI)), 1.01 (0.85-1.21), per 1 SD increment) nor PRAL (adjusted HR (95% CI), 1.07 (0.88-1.30), per 1 SD increment) associated with fracture risk. Further multivariate adjustment for kidney function or stratification by the presence of kidney disease did not modify these null associations.

CONCLUSIONS

The hypothesis that dietary acid load associates with reduced BMD or increased fracture risk was not supported by this study in community-dwelling elderly individuals. Renal function did not influence on this null finding.

Carotenoid derivatives inhibit nuclear factor kappa B activity in bone and cancer cells by targeting key thiol groups

Aberrant activation of the nuclear factor kappa B (NFkB) transcription system contributes to cancer progression, and has a harmful effect on bone health. Several major components of the NFkB pathway such as IkB Kinase (IKK) and the NFkB subunits contain cysteine residues that are critical for their activity. The interaction of electrophiles with these cysteine residues results in NFkB inhibition. Carotenoids, hydrophobic plant pigments, are devoid of electrophilic groups, and we have previously demonstrated that carotenoid derivatives, but not the native compounds activate the Nrf2 transcription system. The aim of the current study was to examine whether carotenoid derivatives inhibit NFkB, and, if so, to determine the molecular mechanism underpinning the inhibitory action. We report in the present study that a mixture of oxidized derivatives, prepared by ethanol extraction from partially oxidized lycopene preparation, inhibited NFkB reporter gene activity. In contrast, the intact carotenoid was inactive. A series of synthetic dialdehyde carotenoid derivatives inhibited reporter activity as well as several stages of the NFkB pathway in both cancer and bone cells. The activity of the carotenoid derivatives depended on the reactivity of the electrophilic groups in reactions such as Michael addition to sulfhydryl groups of proteins. Specifically, carotenoid derivatives directly interacted with two key proteins of the NFkB pathway: the IKKβ and the p65 subunit. Direct interaction with IKKβ was found in an in vitro kinase assay with a recombinant enzyme. The inhibition by carotenoid derivatives of p65 transcriptional activity was observed in a reporter gene assay performed in the presence of excess p65. This inhibition action resulted, at least in part, from direct interaction of the carotenoid derivative with p65 leading to reduced binding of the protein to DNA as evidenced by electrophoretic mobility shift assay (EMSA) experiments. Importantly, we found by using mutation in key cysteine residues of both p65 and IKK that specific thiol groups are essential for NFkB inhibition by carotenoid derivatives. In conclusion, we propose that electrophilic carotenoid derivatives contribute to cancer prevention as well as bone health maintenance via the inhibition of the NFkB transcription system. Pivotal thiol groups of both IKK and p65 play a key role in this process.

The acid-ash hypothesis revisited: a reassessment of the impact of dietary acidity on bone

The acid-ash hypothesis states that when there are excess blood protons, bone is eroded to provide alkali to buffer the net acidity and maintain physiologic pH. There is concern that with the typical Western diet, we are permanently in a state of net endogenous acid production, which is gradually reducing bone. While it is clear that a high acid-producing diet generates increased urinary acid and calcium excretion, the effect of diet does not always have the expected results on BMD, fracture risk and markers of bone formation and resorption, suggesting that other factors are influencing the effect of acid/alkali loading on bone. High dietary protein, sodium and phosphorus intake, all of which are necessary for bone formation, were thought to be net acid forming and contribute to low BMD and fracture risk, but appear under certain conditions to be beneficial, with the effect of protein being driven by calcium repletion. Dietary salt can increase short-term markers of bone resorption but may also trigger 1,25(OH)2D synthesis to increase calcium absorption; with low calcium intake, salt intake may be inversely correlated with BMD but with high calcium intake, salt intake was positively correlated with BMD. With respect to the effect of phosphorus, the data are conflicting. Inclusion of an analysis of calcium intake may help to reconcile the contradictory results seen in many of the studies of bone. The acid-ash hypothesis could, therefore, be amended to state that with an acid-producing diet and low calcium intake, bone is eroded to provide alkali to buffer excess protons but where calcium intake is high the acid-producing diet may be protective.

Bone nutrients for vegetarians

The process of bone mineralization and resorption is complex and is affected by numerous factors, including dietary constituents. Although some dietary factors involved in bone health, such as calcium and vitamin D, are typically associated with dairy products, plant-based sources of these nutrients also supply other key nutrients involved in bone maintenance. Some research suggests that vegetarian diets, especially vegan diets, are associated with lower bone mineral density (BMD), but this does not appear to be clinically significant. Vegan diets are not associated with an increased fracture risk if calcium intake is adequate. Dietary factors in plant-based diets that support the development and maintenance of bone mass include calcium, vitamin D, protein, potassium, and soy isoflavones. Other factors present in plant-based diets such as oxalic acid and phytic acid can potentially interfere with absorption and retention of calcium and thereby have a negative effect on BMD. Impaired vitamin B-12 status also negatively affects BMD. The role of protein in calcium balance is multifaceted. Overall, calcium and protein intakes in accord with Dietary Reference Intakes are recommended for vegetarians, including vegans. Fortified foods are often helpful in meeting recommendations for calcium and vitamin D. Plant-based diets can provide adequate amounts of key nutrients for bone health.

Diet-induced weight loss: the effect of dietary protein on bone

High-protein (>30% of energy from protein or >1.2 g/kg/day) and moderately high-protein (22% to 29% of energy from protein or 1.0 to 1.2 g/kg/day) diets are popular for weight loss, but the effect of dietary protein on bone during weight loss is not well understood. Protein may help preserve bone mass during weight loss by stimulating insulin-like growth factor 1, a potent bone anabolism stimulator, and increasing intestinal calcium absorption. Protein-induced acidity is considered to have minimal effect on bone resorption in adults with normal kidney function. Both the quantity and predominant source of protein influence changes in bone with diet-induced weight loss. Higher-protein, high-dairy diets may help attenuate bone loss during weight loss.