This is a longstanding question that has likely encouraged some people to take the vitamin.
Vitamin D is sometimes called the “sunshine vitamin” because the skin can naturally create it when exposed to sunlight. Numerous prior studies showed that low blood levels of vitamin D (25-hydroxy vitamin D) were associated with higher risk for depression in later life, but there have been few large-scale randomized trials necessary to determine causation.
This study, called VITAL-DEP (Depression Endpoint Prevention in the Vitamin D and Omega-3 Trial), was an ancillary study to VITAL, a randomized clinical trial of cardiovascular disease and cancer prevention among nearly 26,000 people in the US.
The results were clear. Among the 18,353 randomized participants, the researchers found the risk of depression or clinically relevant depressive symptoms was not significantly different between those receiving active vitamin D3 supplements and those on placebo, and there were no significant differences were seen between treatment groups in mood scores over time.
Read original article here- https://www.massgeneral.org/news/press-release/vitamin-d-effects-on-depression
