Vitamin D supplementation may improve depressive symptoms in adults with depression, according to an in-depth meta-analysis. Conducted by an international team of scientists, the meta-analysis included dozens of research studies from around the world. It was published in the journal Critical journals in food science and nutrition.
Depressive symptoms lead to a significant global disease burden. The therapeutic efficacy of current antidepressants is often insufficient to effectively treat depression. That is why other ways to alleviate the symptoms of depression have been sought, for example, from nutritional research.
Vitamin D is thought to regulate the functions of the central nervous system. Disturbances in these functions have been linked to depression. Additionally, cross-sectional studies have observed an association between vitamin D deficiency and depressive symptoms. However, previous meta-analyses on the effects of vitamin D supplementation on depression have been inconclusive. In a meta-analysis, the results of several different studies are combined and analyzed statistically.
The new meta-analysis on the association of vitamin D supplementation with depression is the largest published to date. In fact, it included results from 41 studies from around the world. These studies investigated the effectiveness of vitamin D in relieving depressive symptoms in adults through randomized, placebo-controlled trials in different populations. The studies included those conducted in patients with depression, in the general population and in people with various physical conditions.
The results of the meta-analysis show that vitamin D supplementation is more effective than a placebo in relieving depressive symptoms in people with depression. There were major differences in the doses of vitamin D used, but the vitamin D supplement was generally 50 to 100 micrograms (2,000 to 4,000 IU) per day.
“Despite the broad scope of this meta-analysis, the certainty of the evidence remains low due to the heterogeneity of the study populations and the risk of bias associated with a large number of studies,” said PhD researcher and lead author Tuomas Mikola from says the Institute of Clinical Medicine at the University of Eastern Finland. The meta-analysis is part of Mikola’s doctoral thesis.
“These results will encourage further high-level clinical trials in patients with depression to better understand the possible role of vitamin D supplementation in the treatment of depression,” concludes Mikola.
Reference: “The effect of vitamin D supplementation on depressive symptoms in adults: a systematic review and meta‐analysis of randomized controlled trials” by Tuomas Mikola, Wolfgang Marx, Melissa M. Lane, Meghan Hockey, Amy Loughman, Sanna Rajapolvi, Tetyana Rocks, Adrienne O’Neil, David Mischoulon, Minna Valkonen-Korhonen, Soili M. Lehto and Anu Ruusunen, July 11, 2022, Critical journals in food science and nutrition.
The meta-analysis was carried out as part of an international collaboration between Finnish, Australian and American researchers.