Large study sheds light on effectiveness of vitamin D, fish oil in preventing heart disease, cancer

A long-awaited research study funded largely by the NHLBI has produced some of the clearest evidence to date about the usefulness of taking the nutritional supplements vitamin D and fish oil to fight heart disease and cancer. But the results of the study were mostly negative in terms of achieving the study’s primary endpoints: reduction of major cardiovascular events and a reduction in cancer.

The VITAL study (Vitamin D and Omega-3 trial), which began in 2009, included nearly 26,000 men and women across the United States. It is believed to be the largest primary prevention trial testing the health effects of these supplements in a community-based sample of adults.

“Overall, they showed that neither fish oil nor vitamin D actually lowered the incidence of heart disease or cancer," said Lawrence Fine, M.D., chief of the Clinical Application and Prevention Branch at the NHLBI, in an interview with National Public Radio, one of more than 80 news outlets that covered the study. "At this point, if one is thinking about supplementation, either omega-3s or vitamin D, talking to your physician or health care provider is the next step," Fine said.

The study results appeared in two papers on fish oil and vitamin D supplementation in The New England Journal of Medicine and were accompanied by an editorial on this topic. Researchers also presented the study simultaneously at the American Heart Association (AHA) Scientific Sessions, on Nov. 10 in Chicago.