Vitamin D intake to attain a desired serum 25-hydroxyvitamin D concentration

Abstract

Determination of the intake required to attain serum 25(OH)D concentrations >75 nmol/L must consider the wide variability in the dose-response curve and basal 25(OH)D concentrations. Projection of the dose-response curves observed in this convenience sample onto the population of the third National Health and Nutrition Examination Survey suggests a dose of 95 microg/d (3800 IU) for those above a 25(OH)D threshold of 55 nmol/L and a dose of 125 microg/d (5000 IU) for those below that threshold.

Lifestyle and Other Factors Explain One-Half of the Variability in the Serum 25-Hydroxyvitamin D Response to Cholecalciferol Supplementation in Healthy Adults

“…It is possible that some of the variability between studies in the predictors of response to supplementation may be due to the intercorrelation of such variables and the impact of collinearity in model building. Overall, our model for baseline concentrations contained 17 factors that explained 32% of the variability in baseline serum 25(OH)D. We confirmed the observations of others that baseline concentrations reflect a variety of personal characteristics; nutritional, behavioral and lifestyle factors; and measures of sun exposure (5,(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)42). Our finding of an association between glucocorticoid use and lower serum 25(OH)D concentrations adds to mixed evidence from previous studies.…”

“…Although our model confirmed the findings of others that response to supplementation varies with season of blood collection and baseline serum 25(OH)D concentration (27,42), other aspects of the analysis were unexpected. For example, we found a significantly greater proportional serum 25(OH)D concentration increase from supplementation in women than in men, a finding that, to our knowledge, has not been reported in other trials (5,21,27,43,44). We may have seen this result because our sample size was very large and we could adjust for many potential confounders.…”

“…Although the definition of an adequate serum concentration remains controversial (12 ng/mL) (5,6), it has been argued that one-quarter of Americans have inadequate serum concentrations of 25- (12)(13)(14)(15)(16)(17)(18)(19)(20) ng/mL), and 8% are deficient (<12 ng/mL) (7,8). However, the National Academy of Medicine (NAM) made relatively minor changes to DRIs in 2010, stating that 2016 American Society for Nutrition.…”

“…Many factors are known to be associated with serum 25(OH)D concentrations, including sun exposure, BMI, skin pigmentation, medications, and comorbidities (5,(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26), but, to our knowledge, there is limited evidence on a few factors that may affect the magnitude of serum response to cholecalciferol supplementation, e.g., baseline serum 25(OH)D, BMI, age, calcium intake, and season (27,28). The NAM provides intake recommendations by age and sex, but it is unclear whether supplementation should be varied according to vitamin D status, weight, or other factors (7).…”

Calcium and vitamin D supplements administration in patients with nephrolithiasis; an observational prospective study

“…In contrast, another study revealed no significant association between nephrolithiasis and total and supplemental vitamin D intake (15). Similarly, average urinary calcium excretion was not elevated significantly with vitamin D3 supplements intake among the 138 individuals included in the study conducted by Aloia et al (16). However, two recent studies have found an inverse relationship between vitamin D and kidney stones.…”