Vitamin D₃ supplementation does not modify cardiovascular risk profile of adults with inadequate vitamin D status

The Nutrition Societies in Germany, Austria, and Switzerland recommend a daily intake of 20 µg vitamin D₃ for adults when endogenous synthesis is absent. The current study aimed to elucidate whether this vitamin D₃ dose impacts cardiovascular risk markers of adults during the winter months.

The study was conducted in Halle (Saale), Germany (51^o northern latitude) as a placebo-controlled, double-blinded, randomised trial (from January to April). A total of 105 apparently healthy subjects (male and female, 20-71 years old) were included. Subjects were randomly allocated to two groups. One group received a daily 20-µg vitamin D₃ dose (n = 54), and the other group received a placebo (n = 51) for 12 weeks. Outcome measures included blood pressure, heart rate, concentrations of renin, aldosterone, serum lipids and vascular calcification markers, and haematologic variables such as pro-inflammatory monocytes.

Blood pressure and systemic cardiovascular risk markers remained unchanged by vitamin D₃ supplementation, although serum 25-hydroxyvitamin D₃ increased from 38 ± 14 to 73 ± 16 nmol/L at week 12. The placebo and vitamin D groups did not differ in their final cardiovascular risk profile.

Daily supplementation of 20 µg vitamin D₃ during winter is unlikely to change cardiovascular risk profile.