Vitamin D and Cardio-Metabolic Risk Factors in Overweight Adults: An Overview of the Evidence.

BACKGROUND Several studies have suggested a potential association between low vitamin D serum levels and several pathological conditions apart from the well-known bone disorders. Thus, vitamin D insufficiency has been linked to cardiometabolic risk factors including obesity, insulin resistance, hypertension, dyslipidemia, as well as type 2 diabetes and cardiovascular disease. OBJECTIVE This review intends to provide an overview of recent evidence from clinical studies on vitamin D [25- hydroxyvitamin D (25(OH)D)] and cardiometabolic risk factors in overweight adults. Furthermore, we also discussed potential mechanisms and limits of the retrieved results. METHODS The search process was based on the selection of publications (RCT) listed in PubMed and Cochrane Library databases. RESULTS Vitamin D status evidenced an inversely strong association with subcutaneous adipose tissue and visceral adiposity, but not significantly related to other bodyweight measures (i.e., body mass index). Studies have shown a potential inverse association of hypovitaminosis D with insulin resistance and cardiovascular risk factors. CONCLUSION The mechanisms by which vitamin D deficiency enhances adiposity, as well as putative association with metabolic syndrome features, remain still unclear. Further investigation would be required to conclude whether vitamin D has an independent role in preventing cardiometabolic disorders.