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Vitamin D3 supplementation (4000 IU/d for 1 y) eliminates differences in circulating 25-hydroxyvitamin D between
Elizabeth Garrett-Mayer1, Carol L Wagner, Bruce W Hollis
1Division of Biostatistics and Epidemiology, Department of Medicine, Medical University of South Carolina, Charleston, USA.
Background:
African Americans suffer disproportionately from diabetes and cardiovascular disease and are significantly more likely to have suboptimal concentrations of circulating 25-hydroxyvitamin D [25(OH)D]. The results of epidemiologic and observational studies suggest that there is a link between vitamin D deficiency and the risk of cardiometabolic disorders, which underscores the importance of maintaining healthy concentrations of 25(OH)D.
Objective:
The objective was to investigate whether daily supplementation with 4000 IU vitamin D(3) for 1 y would eliminate any disparities in circulating concentrations of 25(OH)D between African American and white men.
Design:
Serum concentrations of 25(OH)D were measured every 2 mo in 47 subjects who received a daily oral dose of 4000 IU vitamin D(3) for 1 y.
Results:
More than 90% of African Americans had serum concentrations of 25(OH)D <32 ng/mL, and approximately two-thirds had serum concentrations <20 ng/mL. Furthermore, there were significant disparities in serum concentrations of 25(OH)D between African American and white men. Supplementation with 4000 IU/d for 1 y eliminated any significant differences in circulating concentrations of 25(OH)D between African American and white men.
Conclusion:
The results of this clinical study show the feasibility and efficacy of this approach in the elimination of hypovitaminosis D, which is a widespread health disparity among African Americans. This trial was registered at clinicaltrials.gov as NCT01045109.
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