Hypovitaminosis D prevalence and determinants among African American and white women of reproductive age: third National Health and Nutrition Examination Survey, 1988–1994,

Abstract

The high prevalence of hypovitaminosis D among African American women warrants further examination of vitamin D recommendations for these women. The determinants of hypovitaminosis D among women should be considered when these women are advised on dietary intake and supplement use.

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.…”

“…At baseline, 17 factors were independently associated with baseline serum 25(OH)D concentrations, but we found that 50% of the variability in an individualÕs response to supplementation could be explained by baseline serum 25(OH)D concentration and just a few other factors. A greater proportional serum response was seen with a lower baseline serum 25(OH)D concentration, being female, optimal adherence, 4 584 [21] 274 [25] 286 [26] 192 [22] 225 [25] TABLE season of baseline and year 1 blood draws, wearing pants and sleeves when out in the sun, physical activity, and personal vitamin D supplement intake beyond that prescribed. The rs10766197 polymorphism of CYP2R1 was significantly associated with serum response in non-Hispanic whites, but it did not improve the explanatory value (R 2 ) of the multivariable model.…”

“…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).…”

TB or Not TB: That Is No Longer the Question

“…Contribution of vitamin D to host defense in TB Because vitamin D production in humans is dependent on exposure to UV light, vitamin D deficiency is prevalent in dark-skinned populations, including individuals of African descent, who are known to have increased susceptibility to TB and other infectious diseases (80)(81)(82)(83)(84)(85)(86). There is evidence that African Americans are both more susceptible to TB infection (84) and contract more severe disease (39).…”

Relation of Vitamin D Status to Congestive Heart Failure and Cardiovascular Events in Dogs

“…Because BCS is an approximate measure of body fat or body mass index31 and 25(OH)D can be sequestered by adipose tissue, it is important to take BCS into consideration. The relatively normal body conditions of both populations, however, likely precluded any influence of body condition on serum 25(OH)D concentrations 34. Also, it is possible that other factors such as breed, sex, or undiagnosed diseases might have impacted results 35, 36, 37, 38.…”