The effects of a 30-month dietary intervention on bone mineral density: The Postmenopausal Health Study

Fortification of Staple Foods for Household Use with Vitamin D: An Overview of Systematic Reviews

Vitamin D deficiency is a global public health concern with significant implications for bone health and chronic disease prevention. Our aim was to summarize the evidence from Cochrane and other systematic reviews evaluating the benefits or harms of vitamin D fortification of staple foods for household use. In April 2023, we systematically searched Ovid MEDLINE, Embase, Epistemonikos and the Cochrane Database of Systematic Reviews for systematic reviews investigating the effects of vitamin D fortification of food in general populations of any age. We used Cochrane methodology and assessed the methodological quality of included studies using AMSTAR (A MeaSurement Tool to Assess Systematic Reviews). We assessed the degree of overlap among reviews. All outcomes included in systematic reviews were assessed. The protocol is registered in PROSPERO (registration number: CRD42023420991). We included 27 systematic reviews out of 5028 records for analysis. Overall, 11 out of 12 systematic reviews calculating pooled estimates reported a significant increase in serum 25(OH)D concentrations. The mean change in serum 25(OH)D concentrations per additional 100 units of vitamin D ranged from 0.7 to 10.8 nmol/L. Fortification of food with vitamin D showed a reduction in the prevalence of vitamin D deficiency based on high-certainty evidence. Parathormone (PTH) levels were described to decrease, bone mineral density to increase, while the effects on other bone turnover markers were inconsistent. Fortification did not significantly impact most anthropometric parameters, but it seemed to positively influence lipid profiles. In summary, fortification of food with vitamin D results in a reduction of vitamin D deficiency and might increase serum 25(OH)D concentrations, to varying extents depending on the fortified vehicle and population characteristics. Additionally, fortification may have a positive impact on bone turnover and lipid metabolism but may only have a limited effect on anthropometric parameters.

A study on the anti-osteoporosis mechanism of isopsoralen based on network pharmacology and molecular experiments

OBJECTIVE

Osteoporosis (OP) is a disease caused by multiple factors. Studies have pointed out that isopsoralen (IPRN) is one of the most effective drugs for the treatment of OP. Based on network pharmacological and molecular experimental analysis, the molecular mechanism of IPRN in osteoporosis is clarified.

METHODS

IPRN target genes and OP-related genes were predicted from the databases. Intersections were obtained and visualized. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed on target genes, which was confirmed by experiments internal and external experiments. Molecular docking was used to verify the binding between IPRN and target proteins. Molecular dynamics (MD) simulates the binding affinity of protein targets and active compounds.

RESULTS

87 IPRN target genes and 242 disease-related targets were predicted. The protein-protein interaction (PPI) network identified 18 IPRN target proteins for the treatment of OP. GO analysis indicated that target genes were involved in biological processes. KEGG analysis showed that pathways such as PI3K/AKT/mTOR were associated with OP. Cell experiments (qPCR and WB) found that the expressions of PI3K, AKT, and mTOR in MC3T3-E1 cells at 10 μM, 20 μM, and 50 μM IPRN concentrations, especially at 20 μM IPRN treatment, were higher than those in the control group at 48 h. Animal experiments also showed that compared with the control group, 40 mg/kg/time IPRN could promote the expression of the PI3K gene in chondrocytes of SD rats.

CONCLUSIONS

This study predicted the target genes of IPRN in the treatment of OP and preliminarily verified that IPRN plays an anti-OP role through the PI3K/AKT/mTOR pathway, which provides a new drug for the treatment of OP.

Dairy products and bone health

Bone mineral mass, geometry and microstructure, hence determinants of fracture risk, result bone accrual during growth and bone loss later in life. Peak bone mass, which is reached by the end of the second decade of life, is mainly determined by genetic factors. Among other factors influencing bone capital, dietary intakes, particularly calcium and protein, play a significant role in peak bone mass attainment. Both nutrients are provided in dairy products, which accounts for 50-60% and 20-30% of the daily calcium and protein intakes, respectively. Children avoiding dairy products are at higher risk of fracture, as are adults or older individuals following a diet devoid of dairy products, like vegans. Various intervention trials have shown some beneficial effects of dairy products on bone capital accumulation during growth and on bone turnover in adults. In observational studies, dairy products intake, particularly the fermented ones, which also provide probiotics in addition to calcium, phosphorus and protein, appear to be associated with a lower risk of hip fracture.

Effect of dietary sources of calcium and protein on hip fractures and falls in older adults in residential care: cluster randomised controlled trial

OBJECTIVE

To assess the antifracture efficacy and safety of a nutritional intervention in institutionalised older adults replete in vitamin D but with mean intakes of 600 mg/day calcium and <1 g/kg body weight protein/day.

DESIGN

Two year cluster randomised controlled trial.

SETTING

60 accredited residential aged care facilities in Australia housing predominantly ambulant residents.

PARTICIPANTS

7195 permanent residents (4920 (68%) female; mean age 86.0 (SD 8.2) years).

INTERVENTION

Facilities were stratified by location and organisation, with 30 facilities randomised to provide residents with additional milk, yoghurt, and cheese that contained 562 (166) mg/day calcium and 12 (6) g/day protein achieving a total intake of 1142 (353) mg calcium/day and 69 (15) g/day protein (1.1 g/kg body weight). The 30 control facilities maintained their usual menus, with residents consuming 700 (247) mg/day calcium and 58 (14) g/day protein (0.9 g/kg body weight).

MAIN OUTCOME MEASURES

Group differences in incidence of fractures, falls, and all cause mortality.

RESULTS

Data from 27 intervention facilities and 29 control facilities were analysed. A total of 324 fractures (135 hip fractures), 4302 falls, and 1974 deaths were observed. The intervention was associated with risk reductions of 33% for all fractures (121 v 203; hazard ratio 0.67, 95% confidence interval 0.48 to 0.93; P=0.02), 46% for hip fractures (42 v 93; 0.54, 0.35 to 0.83; P=0.005), and 11% for falls (1879 v 2423; 0.89, 0.78 to 0.98; P=0.04). The risk reduction for hip fractures and falls achieved significance at five months (P=0.02) and three months (P=0.004), respectively. Mortality was unchanged (900 v 1074; hazard ratio 1.01, 0.43 to 3.08).

CONCLUSIONS

Improving calcium and protein intakes by using dairy foods is a readily accessible intervention that reduces the risk of falls and fractures commonly occurring in aged care residents.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12613000228785.

Effects of combined calcium and vitamin D supplementation on osteoporosis in postmenopausal women: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

The aim of the present study was to explore whether combined calcium and vitamin D supplementation is beneficial for osteoporosis in postmenopausal women.

METHODS

We searched the PubMed, Cochrane library, Web of science and Embase databases and reference lists of eligible articles up to Feb, 2020. Randomized controlled trials (RCTs) evaluating the effect of combined calcium and vitamin D on osteoporosis in postmenopausal women were included in the present study.

RESULTS

Combined calcium and vitamin D significantly increased total bone mineral density (BMD) (standard mean differences (SMD) = 0.537; 95% confidence interval (CI): 0.227 to 0.847), lumbar spine BMD (SMD = 0.233; 95% CI: 0.073 to 0.392; P < 0.001), arms BMD (SMD = 0.464; 95% CI: 0.186 to 0.741) and femoral neck BMD (SMD = 0.187; 95% CI: 0.010 to 0.364). It also significantly reduced the incidence of hip fracture (RR = 0.864; 95% CI: 0.763 to 0.979). Subgroup analysis showed that combined calcium and vitamin D significantly increased femoral neck BMD only when the dose of the vitamin D intake was no more than 400 IU d^-1 (SMD = 0.335; 95% CI: 0.113 to 0.558), but not for a dose more than 400 IU d^-1 (SMD = -0.098; 95% CI: -0.109 to 0.305), and calcium had no effect on the femoral neck BMD. Subgroup analysis also showed only dairy products fortified with calcium and vitamin D had a significant influence on total BMD (SMD = 0.784; 95% CI: 0.322 to 1.247) and lumbar spine BMD (SMD = 0.320; 95% CI: 0.146 to 0.494), but not for combined calcium and vitamin D supplement.

CONCLUSION

Dairy products fortified with calcium and vitamin D have a favorable effect on bone mineral density. Combined calcium and vitamin D supplementation could prevent osteoporosis hip fracture in postmenopausal women.

A Vitamin D, Calcium and Leucine-Enriched Whey Protein Nutritional Supplement Improves Measures of Bone Health in Sarcopenic Non-Malnourished Older Adults: The PROVIDE Study

Alterations in musculoskeletal health with advanced age contribute to sarcopenia and decline in bone mineral density (BMD) and bone strength. This decline may be modifiable via dietary supplementation. To test the hypothesis that a specific oral nutritional supplement can result in improvements in measures of bone health. Participants (n 380) were participants of the PROVIDE study, a 13-week, multicenter, randomized, controlled, double-blind, 2 parallel-group study among non-malnourished older participants (≥ 65 years) with sarcopenia [determined by Short Physical Performance Battery (SPPB; 0-12) scores between 4 and 9, and a low skeletal muscle mass index (SMI; skeletal muscle mass/BW × 100) ≤ 37% in men and ≤ 28% in women using bioelectric impedance analysis] Supplementation of a vitamin D, calcium and leucine-enriched whey protein drink that comprises a full range of micronutrients (active; 2/day) was compared with an iso-caloric control. Serum 25-hydroxyvitamin D [25(OH)D], parathyroid hormone (PTH), biochemical markers of bone formation (osteocalcin; OC, procollagen type 1 amino-terminal propeptide; P1NP) and resorption (carboxy-terminal collagen crosslinks; CTX), insulin like growth factor 1 (IGF-1) and total-body BMD were analysed pre- and post-intervention. Serum 25(OH)D concentrations increased from 51.1 ± 22.9 nmol/L (mean ± SD) to 78.9 ± 21.1 nmol/L in the active group (p < 0.001 vs. control). Serum PTH showed a significant treatment difference (p < 0.001) with a decline in the active group, and increase in the control group. Serum IGF-1 increased in the active group (p < 0.001 vs. control). Serum CTX showed a greater decline in the active group (p = 0.001 vs. control). There were no significant differences in serum OC or P1NP between groups during the intervention. Total body BMD showed a small (0.02 g/cm²; ~ 2%) but significant increase in the active group after supplementation (p = 0.033 vs. control). Consuming a vitamin D, calcium and leucine-enriched whey protein supplement for 13 weeks improved 25(OH)D, suppressed PTH and had small but positive effects on BMD, indicative of improved bone health, in sarcopenic non-malnourished older adults.

The Relationship between Nutrient Patterns and Bone Mineral Density in Postmenopausal Women

In women, the menopausal transition is characterized by acid-base imbalance, estrogen deficiency and rapid bone loss. Research into nutritional factors that influence bone health is therefore necessary. In this study, the relationship between nutrient patterns and nutrients important for bone health with bone mineral density (BMD) was explored. In this cross-sectional analysis, 101 participants aged between 54 and 81 years were eligible. Body composition and BMD analyses were performed using dual-energy X-ray absorptiometry (DXA). Nutrient data were extracted from a 3-day diet diary (3-DDD) using Foodworks 9 and metabolic equivalent (MET-minutes) was calculated from a self-reported New Zealand physical activity questionnaire (NZPAQ). Significant positive correlations were found between intakes of calcium (p = 0.003, r = 0.294), protein (p = 0.013, r = 0.246), riboflavin (p = 0.020, r = 0.232), niacin equivalent (p = 0.010, r = 0.256) and spine BMD. A nutrient pattern high in riboflavin, phosphorus and calcium was significantly positively correlated with spine (p < 0.05, r = 0.197) and femoral neck BMD (p < 0.05, r = 0.213), while the nutrient pattern high in vitamin E, α-tocopherol, β-carotene and omega 6 fatty acids was negatively correlated with hip (p < 0.05, r = −0.215) and trochanter BMD (p < 0.05, r = −0.251). These findings support the hypothesis that a nutrient pattern high in the intake of vitamin E, α-tocopherol and omega 6 fatty acids appears to be detrimental for bone health in postmenopausal women.

Dairy foods and bone health throughout the lifespan: a critical appraisal of the evidence

The consumption of high-Ca, high-protein dairy foods (i.e. milk, cheese, yogurt) is advocated for bone health across the lifespan to reduce the risk of low-trauma fractures. However, to date, the anti-fracture efficacy of dairy food consumption has not been demonstrated in randomised controlled trials but inferred from cross-sectional and prospective studies. The anti-fracture efficacy of dairy food consumption is plausible, but testing this requires a robust study design to ensure outcomes are suitably answering this important public health question. The evidence of skeletal benefits of dairy food consumption is equivocal, not because it may not be efficacious but because the study design and execution are often inadequate. The key issues are compliance with dietary intervention, dropouts, sample sizes and most importantly lack of deficiency before intervention. Without careful appraisal of the design and execution of available studies, precarious interpretations of outcomes may be made from these poorly designed or executed studies, without consideration of how study design may be improved. Dairy food interventions in children are further hampered by heterogeneity in growth: in particular sex and maturity-related differences in the magnitude, timing, location and surface-specific site of bone accrual. Outcomes of studies combining children of different sexes and maturity status may be masked or exaggerated by these differences in growth, so inaccurate conclusions are drawn from results. Until these critical issues in study design are considered in future dairy food interventions, the anti-fracture efficacy of dairy food consumption may remain unknown and continue to be based on conjecture.

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.

Effects of Fermented Milk Products on Bone

Fermented milk products like yogurt or soft cheese provide calcium, phosphorus, and protein. All these nutrients influence bone growth and bone loss. In addition, fermented milk products may contain prebiotics like inulin which may be added to yogurt, and provide probiotics which are capable of modifying intestinal calcium absorption and/or bone metabolism. On the other hand, yogurt consumption may ensure a more regular ingestion of milk products and higher compliance, because of various flavors and sweetness. Bone mass accrual, bone homeostasis, and attenuation of sex hormone deficiency-induced bone loss seem to benefit from calcium, protein, pre-, or probiotics ingestion, which may modify gut microbiota composition and metabolism. Fermented milk products might also represent a marker of lifestyle promoting healthy bone health.

Food Fortification and Supplement Use-Are There Health Implications?

Dietary supplements are a multi-billion dollar industry in the U.S., and their use is increasing exponentially. Additionally, many foods and beverages are increasingly being fortified with single or multiple vitamins and minerals. Consequently, nutrient intakes are exceeding the safe limits established by the Institute of Medicine. In this paper, we examine the benefits and drawbacks of vitamin and mineral supplements and increasing consumption of fortified foods (in addition to dietary intake) in the U.S.

POPULATION

The pros and cons are illustrated using population estimates of folic acid, calcium, and vitamin D intake, highlighting concerns related to overconsumption of nutrients that should be addressed by regulatory agencies.

Factors Influencing Efficacy of Nutrition Education Interventions: A Systematic Review

OBJECTIVE

To examine systematically factors that contribute to the efficacy of nutrition education interventions in promoting behavior change for good health based on their stated objective. In a departure from previous reviews, the researchers investigated factors that lead to success of various types of interventions. Critical analysis of these factors constituted the outcome of this review.

METHODS

This study followed Preferred Reporting Items for Systematic Reviews and Meta-analysis criteria. A total of 246 original articles published between 2009 and 2015 in PubMed, Medline, Web of Science, Academic Search Complete, Science Direct, Cochrane Reviews, ERIC, and PsychLIT were initially considered. The number was screened and scaled down to 40 publications for the final analysis. Quality assessment was based on the Cochrane Handbook for Systematic Reviews of Intervention. Studies were rated as having low risk of bias, moderate risk, or high risk.

RESULTS

Efficacy of nutrition education interventions depended on major factors: interventions that lasted ≥5 months; having ≤3 focused objectives; appropriate design and use of theories; fidelity in interventions; and support from policy makers and management for worksite environmental interventions.

CONCLUSIONS AND IMPLICATIONS

Intervention duration of ≥5 months, ≤3 focused objectives, randomization, use of theories, and fidelity are factors that enhance success of interventions based on the results of this study.

Peripheral skeleton bone strength is positively correlated with total and dairy protein intakes in healthy postmenopausal women

BACKGROUND

Bone mineral content (BMC) and bone mineral density (BMD) are positively correlated with dietary protein intakes, which account for 1-8% of BMC and BMD variances. However, the relation between bone strength and microstructure, which are variables that are not captured by areal bone mineral density (aBMD), and dietary protein intakes, particularly from specific dietary sources, has not been clearly established.

OBJECTIVE

We investigated the association between the peripheral skeleton-predicted failure load and stiffness, bone microstructure, and dietary protein intakes from various origins (animal, divided into dairy and nondairy, and vegetable origins) in healthy postmenopausal women.

DESIGN

In a cross-sectional study in 746 Caucasian women aged 65.0 ± 1.4 y, we measured the aBMD with the use of dual-energy X-ray absorptiometry, the distal radius and tibia bone microstructures with the use of high-resolution peripheral quantitative computerized tomography, and bone strength with the use of a finite element analysis, and we evaluated dietary protein and calcium with the use of a validated food-frequency questionnaire.

RESULTS

Mean dietary calcium and protein intakes were greater than recommended amounts for this class of age. The predicted failure load and stiffness at the distal radius and tibia were positively associated with total, animal, and dairy protein intakes but not with vegetable protein intake. Failure load differences were accompanied by modifications of the aBMD and of cortical and trabecular bone microstructures. The associations remained statistically significant after adjustment for weight, height, physical activity, menopause duration, calcium intake, and the interaction between calcium and protein intake. A principal component analysis of the volumetric BMD and bone microstructure indicated that trabecular bone mainly contributed to the positive association between protein intakes and bone strength.

CONCLUSIONS

These results, which were recorded in a very homogeneous population of healthy postmenopausal women, indicate that there is a beneficial effect of animal and dairy protein intakes on bone strength and microstructure. Specifically, there is a positive association between the bone failure load and stiffness of the peripheral skeleton and dietary protein intake, which is mainly related to changes in the trabecular microstructure. This trial was registered at www.controlled-trials.com as ISRCTN11865958.

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.

Is bone equally responsive to calcium and vitamin D intake from food vs. supplements? Use of (41)calcium tracer kinetic model

Background

Few interventions directly compare equivalent calcium and vitamin D from dairy vs. supplements on the same bone outcomes. The radioisotope calcium-41 (⁴¹Ca) holds promise as a tracer method to directly measure changes in bone resorption with differing dietary interventions.

Objective

Using ⁴¹Ca tracer methodology, determine if 4 servings/day of dairy foods results in greater ⁴¹Ca retention than an equivalent amount of calcium and vitamin D from supplements. Secondary objective was to evaluate the time course for the change in ⁴¹Ca retention.

Methods

In this crossover trial, postmenopausal women (n = 12) were dosed orally with 100 nCi of ⁴¹Ca and after a 180 day equilibration period received dairy (4 servings/day of milk or yogurt; ~ 1300 mg calcium, 400 IU cholecalciferol (vitamin D₃/day)) or supplement treatments (1200 mg calcium carbonate/day and 400 IU vitamin D₃/day) in random order. Treatments lasted 6 weeks separated by a 6 week washout (WO). Calcium was extracted from weekly 24 h urine collections; accelerator mass spectrometry (AMS) was used to determine the ^41/40Ca ratio. Primary outcome was change in ^41/40Ca excretion. Secondary outcome was the time course for change in ⁴¹Ca excretion during intervention and WO periods.

Results

The ^41/40Ca ratio decreased significantly over time during both treatments; there was no difference between treatments. Both treatments demonstrated a significant retention of ⁴¹Ca within 1–2 weeks (p = 0.0007 and p < 0.001 for dairy and supplements, respectively). WO demonstrated a significant decrease (p = 0.0024) in ⁴¹Ca retention within 1–2 weeks, back to pre-intervention levels.

Conclusion

These data demonstrate that urinary ⁴¹Ca retention is increased with an increase in calcium and vitamin D intake regardless of the source of calcium, and the increased retention occurs within 1–2 weeks.

•

Investigated, using ⁴¹Ca tracer, whether bone response to calcium and vitamin D differed based on the source of nutrients, foods vs. supplements.

•

There was no difference in the bone response by treatment group.

•

Both dairy foods and supplements resulted in reduce ⁴¹Ca excretion in urine.

•

Reduction in ⁴¹Ca excretion occurred with 2 weeks of initiating the interventions.

•

Removal of interventions resulted in 41Ca excretion returning to pre-intervention levels

Changes in bone mineral density over time by body mass index in the health ABC study

Obesity appears protective against osteoporosis in cross-sectional studies. However, results from this longitudinal study found that obesity was associated with bone loss over time. Findings underscore the importance of looking at the longitudinal relationship, particularly given the increasing prevalence and duration of obesity among older adults.

INTRODUCTION

Cross-sectional studies have found a positive association between body mass index (BMI) and bone mineral density (BMD), but little is known about the longitudinal relationship in US older adults.

METHODS

We examined average annual rate of change in BMD by baseline BMI in the Health, Aging, and Body Composition Study. Repeated measurement of BMD was performed with dual-energy X-ray absorptiometry (DXA) at baseline and years 3, 5, 6, 8, and 10. Multivariate generalized estimating equations were used to predict mean BMD (femoral neck, total hip, and whole body) by baseline BMI (excluding underweight), adjusting for covariates.

RESULTS

In the sample (n = 2570), 43 % were overweight and 24 % were obese with a mean baseline femoral neck BMD of 0.743 g/cm(2), hip BMD of 0.888 g/cm(2), and whole-body BMD of 1.09 g/cm(2). Change in total hip or whole-body BMD over time did not vary by BMI groups. However, obese older adults lost 0.003 g/cm(2) of femoral neck BMD per year more compared with normal weight older adults (p < 0.001). Femoral neck BMD change over time did not differ between the overweight and normal weight BMI groups (p = 0.74). In year 10, adjusted femoral neck BMD ranged from 0.696 g/cm(2) among obese, 0.709 g/cm(2) among normal weight, and 0.719 g/cm(2) among overweight older adults.

CONCLUSIONS

Findings underscore the importance of looking at the longitudinal relationship between body composition and bone mineral density among older adults, indicating that high body mass may not be protective for bone loss over time.

Effects of Vitamin D3 Supplementation on Lean Mass, Muscle Strength, and Bone Mineral Density During Weight Loss: A Double-Blind Randomized Controlled Trial

OBJECTIVES

To compare the effects of 12 months of vitamin D3 supplementation with that placebo on lean mass, bone mineral density (BMD), and muscle strength in overweight or obese postmenopausal women completing a structured weight-loss program.

DESIGN

Double-blind, placebo-controlled randomized clinical trial.

SETTING

Fred Hutchinson Cancer Research Center, Seattle, Washington.

PARTICIPANTS

Postmenopausal women aged 50 to 75 with a body mass index (BMI) of 25 kg/m(2) or greater and a serum 25-hydroxyvitamin D (25(OH)D) concentration between 10.0 and 32.0 ng/mL (insufficient) (N = 218).

INTERVENTION

Oral vitamin D3 2,000 IU/d or placebo in combination with a lifestyle-based weight loss intervention consisting of a reduction of 500 kcal to 1,000 kcal per day and 225 min/wk of moderate- to vigorous-intensity aerobic exercise.

MEASUREMENTS

Serum 25(OH)D, body composition, and muscle strength were measured before randomization (baseline) and at 12 months. Mean changes of the groups were compared (intention to treat) using generalized estimating equations.

RESULTS

Change in 25(OH)D was significantly different between the vitamin D and placebo groups at 12 months (13.6 ng/mL vs -1.3 ng/mL, P < .001), but no differences in change in lean mass (-0.8 kg vs -1.1 kg, P = .53) or BMD of the spine (-0.01 g/cm(2) vs 0.0 g/cm(2) , P = .82) or right femoral neck (both -0.01 g/cm(2) , P = .49) were detected between the groups. Leg strength decreased in the vitamin D group but not in the placebo group (-2.6 pounds vs 1.8 pounds, P = .03). In women randomized to vitamin D, achieving repletion (25(OH)D ≥ 32 ng/mL) did not alter results.

CONCLUSION

Vitamin D3 supplementation during weight-loss decreased leg strength but did not alter changes in lean mass or BMD in postmenopausal women with vitamin D insufficiency.

Effects of Dairy Products Consumption on Health: Benefits and Beliefs--A Commentary from the Belgian Bone Club and the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases

Dairy products provide a package of essential nutrients that is difficult to obtain in low-dairy or dairy-free diets, and for many people it is not possible to achieve recommended daily calcium intakes with a dairy-free diet. Despite the established benefits for bone health, some people avoid dairy in their diet due to beliefs that dairy may be detrimental to health, especially in those with weight management issues, lactose intolerance, osteoarthritis, rheumatoid arthritis, or trying to avoid cardiovascular disease. This review provides information for health professionals to enable them to help their patients make informed decisions about consuming dairy products as part of a balanced diet. There may be a weak association between dairy consumption and a possible small weight reduction, with decreases in fat mass and waist circumference and increases in lean body mass. Lactose intolerant individuals may not need to completely eliminate dairy products from their diet, as both yogurt and hard cheese are well tolerated. Among people with arthritis, there is no evidence for a benefit to avoid dairy consumption. Dairy products do not increase the risk of cardiovascular disease, particularly if low fat. Intake of up to three servings of dairy products per day appears to be safe and may confer a favourable benefit with regard to bone health.

Nutrition and bone health in women after the menopause

Osteoporosis affects one out of three postmenopausal women. Their remaining lifetime risk of fragility fractures exceeds that of breast cancer. The risk of osteoporosis and/or fragility fractures can be reduced through healthy lifestyle changes. These include adequate dietary intakes of calcium, vitamin D and protein, regular weight-bearing exercise, reduction in alcohol intake and smoking cessation. European guidance for the diagnosis and management of osteoporosis in postmenopausal women recommends a daily intake of at least 1000 mg/day for calcium, 800 IU/day for vitamin D and 1 g/kg body weight of protein for all women aged over 50 years. The development of programs that encourage lifestyle changes (in particular balanced nutrient intakes) are therefore essential for the reduction of osteoporosis risk.

Consuming the daily recommended amounts of dairy products would reduce the prevalence of inadequate micronutrient intakes in the United States: diet modeling study based on NHANES 2007-2010

Background

A large portion of Americans are not meeting the Dietary Reference Intakes (DRI) for several essential vitamins and minerals due to poor dietary choices. Dairy products are a key source of many of the nutrients that are under consumed, but children and adults do not consume the recommended amounts from this food group. This study modeled the impact of meeting daily recommended amounts of dairy products on population-based nutrient intakes.

Methods

Two-day 24-h dietary recalls collected from participants ≥2 years (n = 8944) from the 2007–2010 What We Eat in America, National Health and Nutrition Examination Survey (NHANES) were analyzed. Databases available from the WWEIA/NHANES and the United States Department of Agriculture (USDA) were used to determine nutrient, food group, and dietary supplement intakes. Modeling was performed by adding the necessary number of dairy servings, using the dairy composite designed by USDA, to each participant’s diet to meet the dairy recommendations outlined by the 2010 Dietary Guidelines for Americans. All analyses included sample weights to account for the NHANES survey design.

Results

The majority of children 4 years and older (67.4–88.8 %) and nearly all adults (99.0–99.6 %) fall below the recommended 2.5-3 daily servings of dairy products. Increasing dairy consumption to recommended amounts would result in a significant reduction in the percent of adults with calcium, magnesium, and vitamin A intakes below the Estimated Average Requirement (EAR) when considering food intake alone (0–2.0 vs. 9.9–91.1 %; 17.3–75.0 vs. 44.7–88.5 %; 0.1–15.1 vs. 15.3–48.0 %, respectively), as well as food and dietary supplement intake. Minimal, but significant, improvements were observed for the percent of people below the EAR for vitamin D (91.7–99.9 vs. 91.8–99.9 %), and little change was achieved for the large percentage of people below the Adequate Intake for potassium.

Conclusions

Increasing dairy food consumption to recommended amounts is one practical dietary change that could significantly improve the population’s adequacy for certain vitamins and minerals that are currently under-consumed, as well as have a positive impact on health.

Calcium revisited, part III: effect of dietary calcium on BMD and fracture risk

Food can be an excellent source of calcium. Dietary calcium is in general as well absorbed as calcium supplements, and exerts the same effects on bone. The main sources are dairy products, but also some vegetables and fruits contain considerable amounts of calcium. Mineral water can serve as a supplement. Cross-sectional, longitudinal and some interventional trials have shown positive effects on bone metabolism, bone density and bone loss. But the effect on fracture incidence is less certain, and that of milk, the most studied dairy product, still unproven.

Calcium and dairy products consumption and association with total hip bone mineral density in women from kosovo

Background and objective:

There is paucity of evidence in southeastern Europe and Kosovo regarding dairy products consumption and association with bone mineral density (BMD). Therefore, the objective of present study was to assess calcium intake and dairy products consumption and to investigate relationship with total hip BMD in a Kosovo women sample.

Methods:

This cross-sectional study included a sample of 185 women divided into respective groups according to total hip BMD. All the study participants completed a food frequency questionnaire and underwent dual-energy X-ray absorptiometry (DEXA) to estimate BMD. Nonparametric tests were performed to compare characteristics of the groups.

Results:

The average dietary calcium intake was 818.41 mg/day. Only 16.75% of the subjects met calcium recommended dietary reference intakes (DRIs). There were no significant differences between low BMD group and normal BMD group regarding average dietary calcium intake, but it was significantly higher in BMDT3 subgroup than in BMDT2 and BMDT1 subgroups.

Conclusions:

The results of this study demonstrate significant relationship of daily dietary calcium intake with upper BMD tertile. Further initiatives are warranted from this study to highlight the importance of nutrition education.

Nutritional aspects of bone health

Bone mass, geometry and microstructure, and bony tissue material level properties determine bone strength, hence the resistance to fracture. At a given age, all these variables are the consequence of the amount accumulated and of the structure developed during growth, up to the so-called peak bone mass, and of the bone loss and microstructure degradation occurring later in life. Genetic factors primarily contribute to the variance of the determinants of bone strength. Nutritional intakes are environmental factors that influence both processes, either directly by modifying modelling and remodelling, or indirectly through changes in calcitropic hormone secretion and action. Some effects of nutrition on the offspring bone could take place during foetal life. There are interplays between genetic factors, nutritional intakes and physical exercise. Among the nutrients, sufficient dietary intakes of calcium and protein are necessary for bone health in childhood and adolescence as well as later in life.

Effects of a three-month therapeutic lifestyle modification program to improve bone health in postmenopausal Korean women in a rural community: a randomized controlled trial

In this randomized controlled trial, we examined the effects of a 3-month therapeutic lifestyle modification (TLM) intervention on knowledge, self-efficacy, and health behaviors related to bone health in postmenopausal women in rural Korea. Forty-one women ages 45 or older were randomly assigned to either the intervention (n = 21) or control (n = 20) group. The intervention group completed a 12-week, 24-session TLM program of individualized health monitoring, group health education, exercise, and calcium-vitamin D supplementation. Compared with the control group, the intervention group showed significant increases in knowledge and self-efficacy and improvement in diet and exercise after 12 weeks, providing evidence that a comprehensive TLM program can be effective in improving health behaviors to maintain bone health in women at high risk of osteoporosis.

Dairy products, yogurts, and bone health

Fracture risk is determined by bone mass, geometry, and microstructure, which result from peak bone mass (the amount attained at the end of pubertal growth) and from the amount of bone lost subsequently. Nutritional intakes are an important environmental factor that influence both bone mass accumulation during childhood and adolescence and bone loss that occurs in later life. Bone growth is influenced by dietary intake, particularly of calcium and protein. Adequate dietary calcium and protein are essential to achieve optimal peak bone mass during skeletal growth and to prevent bone loss in the elderly. Dairy products are rich in nutrients that are essential for good bone health, including calcium, protein, vitamin D, potassium, phosphorus, and other micronutrients and macronutrients. Studies supporting the beneficial effects of milk or dairy products on bone health show a significant inverse association between dairy food intake and bone turnover markers and a positive association with bone mineral content. Fortified dairy products induce more favorable changes in biochemical indexes of bone metabolism than does calcium supplementation alone. The associations between the consumption of dairy products and the risk of hip fracture are less well established, although yogurt intake shows a weakly positive protective trend for hip fracture. By consuming 3 servings of dairy products per day, the recommended daily intakes of nutrients essential for good bone health may be readily achieved. Dairy products could therefore improve bone health and reduce the risk of fractures in later life.

Vitamin D: link between osteoporosis, obesity, and diabetes?

Vitamin D (1,25(OH)₂D₃) is a steroid hormone that has a range of physiological functions in skeletal and nonskeletal tissues, and can contribute to prevent and/or treat osteoporosis, obesity, and Type 2 diabetes mellitus (T2DM). In bone metabolism, vitamin D increases the plasma levels of calcium and phosphorus, regulates osteoblast and osteoclast the activity, and combats PTH hypersecretion, promoting bone formation and preventing/treating osteoporosis. This evidence is supported by most clinical studies, especially those that have included calcium and assessed the effects of vitamin D doses (≥800 IU/day) on bone mineral density. However, annual megadoses should be avoided as they impair bone health. Recent findings suggest that low serum vitamin D is the consequence (not the cause) of obesity and the results from randomized double-blind clinical trials are still scarce and inconclusive to establish the relationship between vitamin D, obesity, and T2DM. Nevertheless, there is evidence that vitamin D inhibits fat accumulation, increases insulin synthesis and preserves pancreatic islet cells, decreases insulin resistance and reduces hunger, favoring obesity and T2DM control. To date, there is not enough scientific evidence to support the use of vitamin D as a pathway to prevent and/or treat obesity and T2DM.

Additional benefit in CVD risk indices derived from the consumption of fortified milk when combined with a lifestyle intervention

OBJECTIVE

The current study aimed to evaluate the effect of fortified milk combined with a lifestyle and counselling programme on several CVD risk factors after a 3-month dietary intervention.

DESIGN

Hypercholesterolaemic adults were randomized to a group supplemented with low-fat milk that was enriched with phytosterols, α-linolenic and linoleic fatty acids, vitamins and antioxidants (enriched milk group, EMG: n 40), a placebo milk group (PMG: n 36) or a control group (CG: n 25). The EMG and PMG consumed respectively 500 ml of enriched milk or placebo milk daily and attended biweekly counselling sessions over a 3-month period.

SETTING

Harokopio University, Athens, Greece.

SUBJECTS

A sample of 101 hypercholesterolemic adults aged 40-60 years.

RESULTS

Regarding lifestyle changes, total and saturated fat intakes decreased significantly in both intervention groups compared with the CG (P < 0·005). Furthermore, total steps were increased (P = 0·029) and BMI was decreased (P = 0·017) significantly in both intervention groups compared with the CG. Regarding biochemical indices, EPA content in erythrocyte membranes increased (P < 0·001) while serum C-reactive protein decreased (P = 0·003) significantly in both intervention groups compared with the CG. Finally, significant increases in plasma folic acid and vitamin B12 levels and a significant decrease in homocysteine levels were observed in the EMG compared with the PMG and CG (all P < 0·001). A favourable change in LDL cholesterol:HDL cholesterol was also observed in the EMG and tended to be significant compared with the PMG and CG (P = 0·066).

CONCLUSIONS

The present study showed that consumption of fortified milk accompanied with lifestyle counselling induces extra benefits in terms of LDL cholesterol:HDL cholesterol and serum homocysteine levels.

Vitamin D supplementation for prevention of mortality in adults

BACKGROUND

Available evidence on the effects of vitamin D on mortality has been inconclusive. In a recent systematic review, we found evidence that vitamin D3 may decrease mortality in mostly elderly women. The present systematic review updates and reassesses the benefits and harms of vitamin D supplementation used in primary and secondary prophylaxis of mortality.

OBJECTIVES

To assess the beneficial and harmful effects of vitamin D supplementation for prevention of mortality in healthy adults and adults in a stable phase of disease.

SEARCH METHODS

We searched The Cochrane Library, MEDLINE, EMBASE, LILACS, the Science Citation Index-Expanded and Conference Proceedings Citation Index-Science (all up to February 2012). We checked references of included trials and pharmaceutical companies for unidentified relevant trials.

SELECTION CRITERIA

Randomised trials that compared any type of vitamin D in any dose with any duration and route of administration versus placebo or no intervention in adult participants. Participants could have been recruited from the general population or from patients diagnosed with a disease in a stable phase. Vitamin D could have been administered as supplemental vitamin D (vitamin D3 (cholecalciferol) or vitamin D2 (ergocalciferol)) or as an active form of vitamin D (1α-hydroxyvitamin D (alfacalcidol) or 1,25-dihydroxyvitamin D (calcitriol)).

DATA COLLECTION AND ANALYSIS

Six review authors extracted data independently. Random-effects and fixed-effect meta-analyses were conducted. For dichotomous outcomes, we calculated the risk ratios (RRs). To account for trials with zero events, we performed meta-analyses of dichotomous data using risk differences (RDs) and empirical continuity corrections. We used published data and data obtained by contacting trial authors.To minimise the risk of systematic error, we assessed the risk of bias of the included trials. Trial sequential analyses controlled the risk of random errors possibly caused by cumulative meta-analyses.

MAIN RESULTS

We identified 159 randomised clinical trials. Ninety-four trials reported no mortality, and nine trials reported mortality but did not report in which intervention group the mortality occurred. Accordingly, 56 randomised trials with 95,286 participants provided usable data on mortality. The age of participants ranged from 18 to 107 years. Most trials included women older than 70 years. The mean proportion of women was 77%. Forty-eight of the trials randomly assigned 94,491 healthy participants. Of these, four trials included healthy volunteers, nine trials included postmenopausal women and 35 trials included older people living on their own or in institutional care. The remaining eight trials randomly assigned 795 participants with neurological, cardiovascular, respiratory or rheumatoid diseases. Vitamin D was administered for a weighted mean of 4.4 years. More than half of the trials had a low risk of bias. All trials were conducted in high-income countries. Forty-five trials (80%) reported the baseline vitamin D status of participants based on serum 25-hydroxyvitamin D levels. Participants in 19 trials had vitamin D adequacy (at or above 20 ng/mL). Participants in the remaining 26 trials had vitamin D insufficiency (less than 20 ng/mL).Vitamin D decreased mortality in all 56 trials analysed together (5,920/47,472 (12.5%) vs 6,077/47,814 (12.7%); RR 0.97 (95% confidence interval (CI) 0.94 to 0.99); P = 0.02; I(2) = 0%). More than 8% of participants dropped out. 'Worst-best case' and 'best-worst case' scenario analyses demonstrated that vitamin D could be associated with a dramatic increase or decrease in mortality. When different forms of vitamin D were assessed in separate analyses, only vitamin D3 decreased mortality (4,153/37,817 (11.0%) vs 4,340/38,110 (11.4%); RR 0.94 (95% CI 0.91 to 0.98); P = 0.002; I(2) = 0%; 75,927 participants; 38 trials). Vitamin D2, alfacalcidol and calcitriol did not significantly affect mortality. A subgroup analysis of trials at high risk of bias suggested that vitamin D2 may even increase mortality, but this finding could be due to random errors. Trial sequential analysis supported our finding regarding vitamin D3, with the cumulative Z-score breaking the trial sequential monitoring boundary for benefit, corresponding to 150 people treated over five years to prevent one additional death. We did not observe any statistically significant differences in the effect of vitamin D on mortality in subgroup analyses of trials at low risk of bias compared with trials at high risk of bias; of trials using placebo compared with trials using no intervention in the control group; of trials with no risk of industry bias compared with trials with risk of industry bias; of trials assessing primary prevention compared with trials assessing secondary prevention; of trials including participants with vitamin D level below 20 ng/mL at entry compared with trials including participants with vitamin D levels equal to or greater than 20 ng/mL at entry; of trials including ambulatory participants compared with trials including institutionalised participants; of trials using concomitant calcium supplementation compared with trials without calcium; of trials using a dose below 800 IU per day compared with trials using doses above 800 IU per day; and of trials including only women compared with trials including both sexes or only men. Vitamin D3 statistically significantly decreased cancer mortality (RR 0.88 (95% CI 0.78 to 0.98); P = 0.02; I(2) = 0%; 44,492 participants; 4 trials). Vitamin D3 combined with calcium increased the risk of nephrolithiasis (RR 1.17 (95% CI 1.02 to 1.34); P = 0.02; I(2) = 0%; 42,876 participants; 4 trials). Alfacalcidol and calcitriol increased the risk of hypercalcaemia (RR 3.18 (95% CI 1.17 to 8.68); P = 0.02; I(2) = 17%; 710 participants; 3 trials).

AUTHORS' CONCLUSIONS

Vitamin D3 seemed to decrease mortality in elderly people living independently or in institutional care. Vitamin D2, alfacalcidol and calcitriol had no statistically significant beneficial effects on mortality. Vitamin D3 combined with calcium increased nephrolithiasis. Both alfacalcidol and calcitriol increased hypercalcaemia. Because of risks of attrition bias originating from substantial dropout of participants and of outcome reporting bias due to a number of trials not reporting on mortality, as well as a number of other weaknesses in our evidence, further placebo-controlled randomised trials seem warranted.

Nutrition and bone health: turning knowledge and beliefs into healthy behaviour

Primary osteoporosis prevention requires healthy behaviours, such as regular physical exercise and adequate dietary intakes of calcium, vitamin D and protein. Calcium and vitamin D can decrease postmenopausal bone loss and prevent fracture risk. However, there is still a high prevalence of calcium and vitamin D insufficiency in women aged 50+ years. Dietary sources of these nutrients are the preferred choice, and dairy products represent a valuable dietary source of calcium due to the high content, high absorptive rate and relatively low cost. Furthermore, dairy products also contain other key nutrients including vitamin D, phosphorus and protein that contribute to bone health. Studies of women's beliefs and behaviours with respect to osteoporosis highlight poor knowledge of the importance of dietary nutrient intakes and low concern regarding bone health. Osteoporosis educational programmes exist to help women change behaviours relevant to bone health. Such programmes can have positive influences on women's knowledge, attitudes, perceived norms, motivation and behaviours. Increased awareness of the consequences of low calcium and vitamin D intakes may promote women's attitudes towards dietary sources, in particular dairy products, and lead to better adherence to health recommendations. Increasing dietary nutrient intakes through educational initiatives should be further developed to aid the prevention of osteoporosis and the efficacy of osteoporosis management.

A multicomponent lifestyle intervention produces favourable changes in diet quality and cardiometabolic risk indices in hypercholesterolaemic adults

BACKGROUND

To date, there are no dietary intervention studies available jointly examining the changes produced in cardiometabolic risk indices and diet quality assessed with the Healthy Eating Index 2005 (HEI-2005). The present study aimed to evaluate the effect of a 3-month multicomponent lifestyle intervention on several cardiometabolic risk indices, physical activity levels and diet quality.

METHODS

A total sample of 108 hypercholesterolaemic adults (40-60 years old) were randomised to two intervention groups provided with and instructed to consume daily: (i) plain milk (n = 37) or (ii) enriched milk (n = 40) respectively; both groups were attending a 3-month dietary counselling programme. For the needs of the present study both intervention groups were analysed together IG: n = 77) and were compared against a control group following usual diet (CG: n = 31).

RESULTS

Regarding diet quality HEI scores for 'milk' (P = 0.021), 'dark green/orange vegetables and legumes' (P = 0.050) and 'total HEI score' (P = 0.045) were improved in the IG compared to the CG. The IG also improved 'whole grains' and 'calories from solid fats, alcoholic beverages and added sugars' scores compared to their baseline values. Both groups improved the 'total vegetable' HEI score. Regarding physical activity levels and cardiometabolic risk indices, the IG significantly increased the daily number of steps (P = 0.005) and decreased body weight (P = 0.021), body mass index (P = 0.019) and waist circumference (P = 0.027) to a higher extent compared to the changes observed in the CG. Moreover, the IG significantly decreased systolic (P = 0.001) and diastolic blood pressure (P = 0.050) compared to baseline values.

CONCLUSIONS

The present study revealed that this 3-month lifestyle and nutrition counselling intervention programme appears to have favourable effects on diet quality, physical activity levels, anthropometric and certain cardiometabolic risk indices.

Meeting and exceeding dairy recommendations: effects of dairy consumption on nutrient intakes and risk of chronic disease

The 2010 Dietary Guidelines for Americans indicate the US population is experiencing an epidemic of overweight and obesity while maintaining a nutrient-poor, energy-dense diet associated with an increased risk of osteoarthritis, cardiovascular disease, and type 2 diabetes. To build upon the review of published research in the Report of the Dietary Guidelines Advisory Committee on the Dietary Guidelines for Americans, 2010, this article aims to review the scientific literature pertaining to the consumption of dairy foods and the effects of dairy consumption on nutrient intakes and chronic disease risk published between June 2010, when the report was released, and September 2011. PubMed was searched for articles using the following key words: dairy, milk, nutrient intake, bone health, body composition, cardiovascular disease, type 2 diabetes, and blood pressure. Evidence indicates that increasing dairy consumption to the recommended amount, i.e., three servings daily for individuals ≥9 years of age, helps close gaps between current nutrient intakes and recommendations. Consuming more than three servings of dairy per day leads to better nutrient status and improved bone health and is associated with lower blood pressure and reduced risk of cardiovascular disease and type 2 diabetes.

Dairy in adulthood: from foods to nutrient interactions on bone and skeletal muscle health

The risk of fragility fractures exponentially increases with aging. Reduced mass and strength of both bone in osteoporosis and skeletal muscle in sarcopenia play a key role in the age-related incidence of fragility fractures. Undernutrition is often observed in the elderly, particularly in those subjects experiencing osteoporotic fractures, more likely as a cause than a consequence. Calcium (Ca), inorganic phosphate (Pi), vitamin D, and protein are nutrients that impact bone and skeletal muscle integrity. Deficiency in the supply of these nutrients increases with aging. Dairy foods are rich in Ca, Pi, and proteins and in many countries are fortified with vitamin D. Dairy foods are important souces of these nutrients and go a long way to meeting the recommendations, which increase with aging. This review emphaszes the interactions between these 4 nutrients, which, along with physical activity, act through cellular and physiological pathways favoring the maintenance of both bone and skeletal muscle structure and function.

Changes in parameters of bone metabolism in postmenopausal women following a 12-month intervention period using dairy products enriched with calcium, vitamin D, and phylloquinone (vitamin K(1)) or menaquinone-7 (vitamin K (2)): the Postmenopausal Health Study II

The objective of the present study was to examine the effect of dairy products enriched with calcium, vitamin D(3), and phylloquinone (vitamin K(1)) or menaquinone-7 (vitamin K(2)) on parameters of bone metabolism in postmenopausal women following a 12-month intervention. Postmenopausal women were divided into three intervention groups and a control group (CG). All three intervention groups attended biweekly sessions and received fortified dairy products providing daily 800 mg of calcium and 10 μg of vitamin D(3) (CaD). Furthermore, in two of the three intervention groups the dairy products were also enriched with vitamin K, providing daily 100 μg of either phylloquinone (CaDK1) or menaquinone-7 (CaDK2). The increase observed for serum 25(OH)D levels in all intervention groups and the increase observed for serum IGF-I levels in the CaDK2 group differed significantly compared to the changes observed in CG (P = 0.010 and P = 0.028, respectively). Furthermore, both the CaDK1 and CaDK2 groups had a significantly lower mean serum undercarboxylated osteocalcin to osteocalcin ratio and urine deoxypyridinoline levels at follow-up compared to the CaD and CG groups (P = 0.001 and P = 0.047, respectively). Significant increases in total-body BMD were observed in all intervention groups compared to CG (P < 0.05), while significant increases in lumbar spine BMD were observed only for CaDK1 and CaDK2 compared to CG (P < 0.05) after controlling for changes in serum 25(OH)D levels and dietary calcium intake. In conclusion, the present study revealed more favorable changes in bone metabolism and bone mass indices for the two vitamin K-supplemented groups, mainly reflected in the suppression of serum levels of bone remodeling indices and in the more positive changes in lumbar spine BMD for these two study groups.

The effect of vitamin D on bone and osteoporosis

The main effect of the active vitamin D metabolite 1,25(OH)2D is to stimulate the absorption of calcium from the gut. The consequences of vitamin D deficiency are secondary hyperparathyroidism and bone loss, leading to osteoporosis and fractures, mineralization defects, which may lead to osteomalacia in the long term, and muscle weakness, causing falls and fractures. Vitamin D status is related to bone mineral density and bone turnover. Vitamin D supplementation may decrease bone turnover and increase bone mineral density. Several randomized placebo-controlled trials with vitamin D and calcium showed a significant decrease in fracture incidence. However, very high doses of vitamin D once per year may have adverse effects. When patients with osteoporosis are treated with a bisphosphonate, they should receive a vitamin D and calcium supplement unless the patient is vitamin D replete. These subjects are discussed in detail in this review. Finally, the knowledge gaps and research agenda are discussed.

Vitamin D supplementation for prevention of mortality in adults

BACKGROUND

The available evidence on vitamin D and mortality is inconclusive.

OBJECTIVES

To assess the beneficial and harmful effects of vitamin D for prevention of mortality in adults.

SEARCH STRATEGY

We searched The Cochrane Library, MEDLINE, EMBASE, LILACS, the Science Citation Index Expanded, and Conference Proceedings Citation Index-Science (to January 2011). We scanned bibliographies of relevant publications and asked experts and pharmaceutical companies for additional trials.

SELECTION CRITERIA

We included randomised trials that compared vitamin D at any dose, duration, and route of administration versus placebo or no intervention. Vitamin D could have been administered as supplemental vitamin D (vitamin D(3) (cholecalciferol) or vitamin D(2) (ergocalciferol)) or an active form of vitamin D (1α-hydroxyvitamin D (alfacalcidol) or 1,25-dihydroxyvitamin D (calcitriol)).

DATA COLLECTION AND ANALYSIS

Six authors extracted data independently. Random-effects and fixed-effect model meta-analyses were conducted. For dichotomous outcomes, we calculated the risk ratios (RR). To account for trials with zero events, meta-analyses of dichotomous data were repeated using risk differences (RD) and empirical continuity corrections. Risk of bias was considered in order to minimise risk of systematic errors. Trial sequential analyses were conducted to minimise the risk of random errors.

MAIN RESULTS

Fifty randomised trials with 94,148 participants provided data for the mortality analyses. Most trials included elderly women (older than 70 years). Vitamin D was administered for a median of two years. More than one half of the trials had a low risk of bias. Overall, vitamin D decreased mortality (RR 0.97, 95% confidence interval (CI) 0.94 to 1.00, I(2) = 0%). When the different forms of vitamin D were assessed separately, only vitamin D(3) decreased mortality significantly (RR 0.94, 95% CI 0.91 to 0.98, I(2) = 0%; 74,789 participants, 32 trials) whereas vitamin D(2), alfacalcidol, or calcitriol did not. Trial sequential analysis supported our finding regarding vitamin D(3), corresponding to 161 individuals treated to prevent one additional death. Vitamin D(3) combined with calcium increased the risk of nephrolithiasis (RR 1.17, 95% CI 1.02 to 1.34, I(2) = 0%). Alfacalcidol and calcitriol increased the risk of hypercalcaemia (RR 3.18, 95% CI 1.17 to 8.68, I(2) = 17%). Data on health-related quality of life and health economics were inconclusive.

AUTHORS' CONCLUSIONS

Vitamin D in the form of vitamin D(3) seems to decrease mortality in predominantly elderly women who are mainly in institutions and dependent care. Vitamin D(2), alfacalcidol, and calcitriol had no statistically significant effect on mortality. Vitamin D(3) combined with calcium significantly increased nephrolithiasis. Both alfacalcidol and calcitriol significantly increased hypercalcaemia.

Possible site-specific effect of an intervention combining nutrition and lifestyle counselling with consumption of fortified dairy products on bone mass: the Postmenopausal Health Study II

The aim of the present study was to examine whether a holistic approach combining nutrition and lifestyle counselling with the consumption of milk and yoghurt enriched with calcium, vitamin D(3) and phylloquinone (vitamin K(1)) or menaquinone (vitamin K(2)) would have any additional benefit on bone mineral density (BMD) indices measured at various skeletal sites using two different techniques, dual energy X-ray absorptiometry and quantitative ultrasonography (QUS). A sample of 115 postmenopausal women were randomized to three intervention groups, receiving daily via fortified milk and yoghurt and for 12 months, 800 mg calcium and 10 μg vitamin D(3) (CaD group, n = 26); 800 mg calcium, 10 μg vitamin D(3) and 100 μg vitamin K(1) (CaDK1 group, n = 26); 800 mg calcium, 10 μg vitamin D(3) and 100 μg vitamin K(2) (CaDK2 group, n = 24); and a control group (CO group, n = 39) following their usual diet. All three intervention groups attended biweekly nutrition and lifestyle counselling sessions. Total BMD significantly increased in all three intervention groups and these changes were significantly higher compared to the CO (P < 0.001). Furthermore, the significant increases observed for L2-L4 BMD in the CaDK1 and CaDK2 groups were found to be significantly higher compared to the decrease observed in the CO (P = 0.001). No significant differences were observed for QUS parameters. The combined approach used in the current study led to favourable changes for all three intervention groups in total body BMD, while an additional benefit was observed for L2-L4 BMD in CaDK1 and CaDK2 groups. No significant differences were observed among groups in any of the QUS parameters.

Calcium and vitamin D supplementation through fortified dairy products counterbalances seasonal variations of bone metabolism indices: the Postmenopausal Health Study

PURPOSE

To assess the effectiveness of a dietary intervention combined with fortified dairy products on bone metabolism and bone mass indices in postmenopausal women.

METHODS

Forty postmenopausal women (55-65 years old) were equally randomized into a dietary group (DG), receiving daily and for 30 months, 1,200 mg of calcium and 7.5 μg of vitamin D(3) for the first 12 months that increased to 22.5 μg for the remaining 18 months of intervention through fortified dairy products; and a control group (CG). Differences in the changes of bone metabolism and bone mass indices were examined with repeated measures ANOVA.

RESULTS

A significant increase was observed for PTH levels only in the CG during the first six winter months of intervention (p = 0.049). After 30 months of intervention, during winter, serum 25(OH)D significantly decreased in the CG while remained in the same high levels as in the summer period in the DG. Serum RANKL levels decreased significantly in the DG compared with the increase in the CG during the 30-month intervention period (p = 0.005). Serum CTx decreased significantly in the DG after six (-0.08; -0.12 to -0.03) and 12 (-0.03; -0.08 to -0.02) months of intervention. Finally, the DG had more favorable changes in total body BMD than the CG (p < 0.001).

CONCLUSIONS

Increasing dietary intake of calcium and vitamin D in osteopenic postmenopausal women appears to be effective in producing favorable changes in several bone metabolism and bone mass indices and in counterbalancing seasonal variations in hormonal and biochemical molecules.

Bone health nutrition issues in aging

Bone health is an important issue in aging. Calcium and vitamin D currently have the most focus in published research on nutrition and bone health in aging, although evidence from published research is not conclusive. A systematic review was conducted to determine the impact of dietary and supplemental interventions focused on calcium and vitamin D over the past 10 years. Using key words to search, and search limits (aging population, English), 62 papers were found related to diet, nutrition, and bone; and 157 were found related to calcium and bone. Our review found a positive effect on bone health for supplements; food-based interventions; and educational strategies. Although there may be a publishing bias related to non-significant findings not being published, our results suggest the effectiveness of food based and educational interventions with less economic impact to the individual, as well as less risk of physiological side effects occurring.