To offer a comprehensive overview of the best available evidence linking vitamin D status, including the effect of vitamin D supplementation, to the risk of cardiovascular events.
There is an abundance of plausible mechanisms by which vitamin D might have a favorable effect on the cardiovascular risk profile in the general population. Epidemiological data strongly support such beneficial effects of vitamin D, but initial enthusiasm is giving way to skepticism as larger, well conducted, longitudinal observational trials fail to show an association between serum vitamin D levels and mortality from cardiovascular events. Moreover, the few existing prospective randomized controlled trials with vitamin D supplementation that report the incidence of cardiovascular events show no effect. Fortunately, larger and better designed prospective trials are underway. Nonetheless, one should also acknowledge that true vitamin D deficiency [<25 nmol/l (10 ng/ml)] remains prevalent in the general population and is convincingly associated with overall adverse outcomes.
Currently, robust clinical data are lacking to support raising intake requirements and target vitamin D plasma levels based on a role for vitamin D in preventing cardiometabolic diseases. Nonetheless, the high prevalence of vitamin D deficiency in the general population remains alarming and requires implementation of clear supplementation guidelines.
Laboratory and Clinic of Experimental Medicine and Endocrinology, University Hospital Leuven, Catholic University of Leuven, Leuven, Belgium
Correspondence to Bart Van der Schueren, UZ Gasthuisberg, Herestraat 49, 3000 Leuven, BelgiumTel: +32 16 34 69 94; fax: +32 16 34 69 89; e-mail: firstname.lastname@example.org