Vitamin D Doesn't Prevent Depression in Older Adults, Large Study Finds

A study of more than 18,000 U.S. adults 50 years or older published in JAMA found no evidence that Vitamin D prevents depression, reports CNN . Half of the subjects, who had no clinically relevant depressive symptoms at the start, took 2,000 daily international units of vitamin D3, exceeding the current recommended amount in the United States. The other half took a placebo, with participants monitored for 5.3 years on average. The researchers observed no significant difference between the cohorts in depressive symptoms or mood scores. "There is a longstanding issue of publication bias, in that studies with statistically significant findings get disproportionately published," said University College London Hospital dietitian Brian Power. "This conclusion should be replicated to increase the confidence that there is no effect. Doing so will ensure we don't waste resources into the future."