Taking vitamin D supplements reduces your risk of getting deadly cancers that spread (metastatize) into other parts of the body, a major new study has discovered.
The risk can be reduced by as much as 38 percent—but only if you’re not overweight or obese. The higher your BMI (body-mass index) score, the less protective the supplements will be, say researchers from the VITAL research group.
The optimum dose is 2000 IUs (international units) a day, and the vitamin works best for people with a BMI of less than 25. The overall protective effect is around 17 percent, but that includes all participants, including those with a BMI in excess of 30, which is considered obese. Researchers suggest that overweight and obese people may need to take higher doses to get the same benefits.
The researchers tracked the health and diets of 25,871 volunteers with an average age of 67. During the five years of the study, 1,617 people developed invasive cancer—but there was “a significant” difference” in cases between those taking vitamin D or a placebo, or dummy supplement.
The vitamin had similar protective effects against a range of cancers, which suggests it can block the spread of most forms of the disease. Even when prostate cancer—the most prevalent reported by the group—was removed from the analysis, the positive effects were still there.
(Source: JAMA Network Open, 2020; 3: e2025850)
