Recent evidence suggests that vitamin D intakes above current recommendations may be associated with better health outcomes. However, optimal serum concentrations of 25-hydroxyvitamin D [25(OH)D] have not been defined. This review summarizes evidence from studies that evaluated thresholds for serum 25(OH)D concentrations in relation to bone mineral density (BMD), lower-extremity function, dental health, and risk of falls, fractures, and colorectal cancer. For all endpoints, the most advantageous serum concentrations of 25(OH)D begin at 75 nmol/L (30 ng/mL), and the best are between 90 and 100 nmol/L (36–40 ng/mL). In most persons, these concentrations could not be reached with the currently recommended intakes of 200 and 600 IU vitamin D/d for younger and older adults, respectively. A comparison of vitamin D intakes with achieved serum concentrations of 25(OH)D for the purpose of estimating optimal intakes led us to suggest that, for bone health in younger adults and all studied outcomes in older adults, an increase in the currently recommended intake of vitamin D is warranted. An intake for all adults of ≥1000 IU (40 μg) vitamin D (cholecalciferol)/d is needed to bring vitamin D concentrations in no less than 50% of the population up to 75 nmol/L. The implications of higher doses for the entire adult population should be addressed in future studies.

ContextThe role and dose of oral vitamin D supplementation in nonvertebral fracture prevention have not been well established.ObjectiveTo estimate the effectiveness of vitamin D supplementation in preventing hip and nonvertebral fractures in older persons.Data SourcesA systematic review of English and non-English articles using MEDLINE and the Cochrane Controlled Trials Register (1960-2005), and EMBASE (1991-2005). Additional studies were identified by contacting clinical experts and searching bibliographies and abstracts presented at the American Society for Bone and Mineral Research (1995-2004). Search terms included randomized controlled trial (RCT), controlled clinical trial, random allocation,double-blind method, cholecalciferol,ergocalciferol,25-hydroxyvitamin D, fractures, humans, elderly, falls, and bone density.Study SelectionOnly double-blind RCTs of oral vitamin D supplementation (cholecalciferol, ergocalciferol) with or without calcium supplementation vs calcium supplementation or placebo in older persons (≥60 years) that examined hip or nonvertebral fractures were included.Data ExtractionIndependent extraction of articles by 2 authors using predefined data fields, including study quality indicators.Data SynthesisAll pooled analyses were based on random-effects models. Five RCTs for hip fracture (n = 9294) and 7 RCTs for nonvertebral fracture risk (n = 9820) met our inclusion criteria. All trials used cholecalciferol. Heterogeneity among studies for both hip and nonvertebral fracture prevention was observed, which disappeared after pooling RCTs with low-dose (400 IU/d) and higher-dose vitamin D (700-800 IU/d), separately. A vitamin D dose of 700 to 800 IU/d reduced the relative risk (RR) of hip fracture by 26% (3 RCTs with 5572 persons; pooled RR, 0.74; 95% confidence interval [CI], 0.61-0.88) and any nonvertebral fracture by 23% (5 RCTs with 6098 persons; pooled RR, 0.77; 95% CI, 0.68-0.87) vs calcium or placebo. No significant benefit was observed for RCTs with 400 IU/d vitamin D (2 RCTs with 3722 persons; pooled RR for hip fracture, 1.15; 95% CI, 0.88-1.50; and pooled RR for any nonvertebral fracture, 1.03; 95% CI, 0.86-1.24).ConclusionsOral vitamin D supplementation between 700 to 800 IU/d appears to reduce the risk of hip and any nonvertebral fractures in ambulatory or institutionalized elderly persons. An oral vitamin D dose of 400 IU/d is not sufficient for fracture prevention.

Background: Dental caries and periodontitis are the most common oral diseases and major causes of tooth loss.Aim: To perform a review of global prevalence and incidence of dental caries and periodontitis.Methodology: Inclusion and exclusion criteria were developed. MEDLINE database and EMBASE database were used to search for eligible publications using keywords and MeSH terms. Additionally, WHO databank was used for obtaining dental caries information and PUBMED for a search on trends of dental caries prevalence and severity.Results: Over the last four decades, the prevalence and severity of dentine carious lesions among 5‐ and 12‐year‐olds have declined; the decay‐component is very high, with the lowest prevalence among 12‐year‐olds in high‐income countries, which also had the lowest prevalence among 35‐ to 44‐year‐olds; and the number of retained teeth has increased around the globe. The prevalence of periodontitis is high, with approximately 10% of the global population affected by severe periodontitis. Study heterogeneity and methodological issues hamper comparisons across studies and over time.Conclusion: While the prevalence of dental caries has decreased, the disease is prevalent in all age groups. The prevalence of periodontitis is high. There is insufficient evidence to conclude that the prevalence of periodontitis has changed over time.

Background: Vitamin D may improve muscle strength through a highly specific nuclear receptor in muscle tissue. Objectives: We investigated whether there is an association between 25-hydroxyvitamin D [25(OH)D] concentrations and lower-extremity function in ambulatory older persons, whether that association differs by activity level, and, if so, whether there is an identifiable threshold in the association. Design: The study was a population-based survey of the ambulatory US population aged 60 to ≥90 y (n = 4100). Lower-extremity function according to serum 25(OH)D concentrations was assessed by linear regression analyses and regression plots after control for activity level (inactive or active) and several other potential confounders. Separate analyses were performed for the timed 8-foot (ie, 2.4 m) walk test and a repeated sit-to-stand test. Results: The 8-foot walk test compared subjects in the lowest and highest quintiles of 25(OH)D; the latter group had an average decrease of 0.27 s [95% CI: −0.44, −0.09 s (or 5.6%); P for trend < 0.001]. The sit-to-stand test compared subjects in the lowest and highest quintiles of 25(OH)D; the latter group had an average decrease of 0.67 s [95% CI: −1.11, −0.23 s (or 3.9%); P for trend = 0.017]. In the 25(OH)D reference range of 22.5–94 nmol/L, most of the improvement occurred in subjects with 25(OH)D concentrations between 22.5 and ≈40 nmol/L, and further improvement was seen in the range of 40–94 nmol/L. Stratification by activity level showed no significant effect modification. Conclusion: In both active and inactive ambulatory persons aged ≥60 y, 25(OH)D concentrations between 40 and 94 nmol/L are associated with better musculoskeletal function in the lower extremities than are concentrations < 40 nmol/L.