Vitamin D: Does it help with weight loss?


People who are overweight or obese have additional reasons to be concerned about their vitamin D levels.

“People with increased body fat have lower blood levels of vitamin D compared to people of normal weight,” says the Anne McTiernan, MD, PhD a professor at the Fred Hutchinson Cancer Research Center and author of Starved: A Nutrition Doctor’s Journey from Empty to Full who has researched vitamin D and weight loss.

An article published in September 2019 in Medicina argues that while vitamin D deficiency is not a cause of obesity, there is a strong link between the two. The authors theorize that one reason may be that excess fat, liver, and muscle mass prevent vitamin D absorption.

Another possible explanation, says Anne McTiernan, is that people who are overweight or obese may be exposed to less sun and therefore have lower vitamin D level.

Another factor could be diet. “Low concentration of vitamin D in the blood is very common in people who are characterized as obese, possibly due to insufficient intake of nutrients”notes the Simone PernaPhD, assistant professor in the biology department at the University of Bahrain, who has researched the vitamin D and weight loss.

Whatever the reason, researchers are looking into whether vitamin D supplements could help with weight loss.


Can increasing vitamin D help you lose weight?

Scientists think it’s too early to say for sure whether vitamin D supplements help with weight loss, so they’re continuing to investigate.

For example, in a study published in March 2014 in The American Journal of Clinical Nutrition, 218 postmenopausal women who received a vitamin D supplement lost more weight. Specifically, participants who were overweight or obese followed a weight loss program that included a reduced-calorie diet and exercise. Researchers have found a link between vitamin D and greater weight loss.

“Vitamin D has a direct role in suppressing parathyroid hormone, which promotes and triggers the accumulation of fat in adipose tissue”Dr. Perna estimates.

In general it seems that vitamin D is important even indirectly for weight. However, further studies are needed to confirm whether taking prescription vitamin D supplements helps with weight loss.

With information from