Living in Low-Latitude Regions in the United States Does Not Prevent Poor Vitamin D Status

Abstract

Vitamin D deficiency may occur throughout the life cycle, and is described as an unrecognized epidemic. The risk of deficiency may be increased by darker skin color, overweight and obesity, and low vitamin D intakes, while living in low latitudes and not using protective measures against the sun may decrease risk. However, a recent study reported that Hispanic adults living in the high-sun-exposure area of Miami have a high prevalence of poor vitamin D status in the winter, suggesting that living at low latitudes alone does not protect against vitamin D deficiency. The vitamin D status of Hispanics needs further investigation, given the large number of Hispanics living in southern regions of the United States and the emerging role of vitamin D in numerous health disorders.

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 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).…”

Epidemiological Evidence for Vitamin D and Colorectal Cancer

“…In essence, many people could be at risk for low vitamin D, even in relatively sunny climates. (40) The current recommended intakes of vitamin D (200-600 IU/d depending on age) may be suboptimal for many if not most people. Given the potential benefits of vitamin D against colorectal cancer, and possibly other conditions, higher intakes may be warranted.…”

Vitamin D status and health correlates among German adults

“…A recent study suggests that lower serum 25OHD levels are also associated with a greater risk of future nursing home admission and possibly with mortality in older persons . It is well known that vitamin D status shows a marked seasonal variation as ultraviolet-B radiation is not strong enough during winter time to assure sufficient dermal synthesis of vitamin D. Vitamin D deficiency states appear to be prevalent in populations of different latitudes and ethnic backgrounds (Mc Kenna, 1992;Ovesen et al, 2003;Hashemipour et al, 2004;Heaney, 2004;Meyer et al, 2004;Raiten and Picciano, 2004;Gannage-Yared et al, 2005;Hanley and Davision, 2005;Lucas et al, 2005;Meddeb et al, 2005;Park and Johnson, 2005;Whiting and Calvo, 2005). Specific risk factors of vitamin D deficiency mediated by lack of sunshine exposure include residence at high latitudes and in large cities, high skin pigmentation, cultural dress code or immobility (Semba et al, 2000;Hashemipour et al, 2004;Meyer et al, 2004;Meyer, 2004;GannageYared et al, 2005).…”