Why was this study done?
Many observational (population studies) have shown a relationship between vitamin D status and cardiovascular disease. This study was designed to help define the association between vitamin D and cardiovascular health by determining the effects of vitamin D supplementation on HDL cholesterol levels in overweight and obese subjects.
What did the study find?
Researchers were unable to increase blood levels of vitamin D in participants who took either a multivitamin or a multivitamin plus additional vitamin D (1200 IU/Day) suggesting that sufficient vitamin D supplementation may be higher than 1200 IU/day or that overweight/obese people may metabolize vitamin D differently. Since researchers were unable to increase circulating vitamin D levels to above 75 (nmol/l) they observed no changes in cardiovascular risk levels.
Effects of vitamin D supplementation on 25-hydroxyvitamin D, high-density lipoprotein cholesterol, and other cardiovascular disease risk markers in subjects with elevated waist circumference.
Authors: Maki KC, Rubin MR, Wong LG, McManus JF, Jensen CD, Lawless A. Int J Food Sci Nutr. 2011 Jun;62(4):318-27.
PubMed Citation PMID: 21250901.
PDF Manuscript: Int J Food Sci Nutr, 2011.