Current research does not show enough evidence that vitamin or mineral supplements are beneficial for preventing or treating heart disease, with the exception of folic acid for reducing stroke risk, according to a review article published in the Journal of the American College of Cardiology.
The authors of the review say that the focus should therefore continue to be on the “adoption of diets that are heavy in plant-based foods, from which these vitamins are derived naturally”.
The authors say that, despite high use – a recent study showed that 52% of the US population takes supplements – there is “no agreement on whether individual vitamins or minerals or combination supplements should be taken to prevent or treat heart disease”.
In this review, researchers looked at 179 randomized controlled trials on vitamin and mineral supplement use published from January 2012 to October 2017 to determine if a benefit existed.
Researchers found that data on the four most commonly used supplements—multivitamins, vitamin D, calcium and vitamin C—showed no consistent benefit for the prevention of cardiovascular disease, myocardial infarction or stroke, nor was there a benefit for all-cause mortality. Folic acid alone and B-complex vitamins in which folic acid was a component did show a reduction in stroke; however, niacin (vitamin B3) and antioxidants were associated with an increased risk of all-cause mortality.
‘Designed to fail’
The study has been criticised by parts of the natural health community. Campaign group Alliance for Natural Health (ANH) says that the questions that the meta-analysis sought to answer “were the ones highly likely to yield negative results”.
Study design flaws, says ANH, included using inappropriate nutrient forms (“we’re yet to meet a single person who believes a supermarket or pharmacy ‘multi’ is a useful insurance policy for heart disease”), excluding studies from the review that might have produced positive results and drawing on studies where supplementation periods were “too short or where supplementation was started too late in an individual’s disease cycle”.
In a commentary on its website, ANH concludes: “This meta-analysis was unlikely to give a fundamentally different outcome from the previous meta-analysis informing the U.S. Preventive Services Task Force (USPSTF) on recommendations for vitamin and mineral supplements on CVD because only 15 of the 179 studied included were new. But, it did provide another opportunity to generate negative headlines around the world.”
Responding to article in the US, trade association the Natural Products Association, insisted that supplements “are important to the vast majority of Americans”. The group’s CEO and president, Dan Fabricant (and a former senior FDA official) commented: “In an ideal world, everyone would get the nutrients they need by eating a balanced diet, but unfortunately that is not the case,” said Daniel Fabricant, President and CEO of NPA. “While there is no magic pill just as there is no one single food providing all of your daily needs, supplementing your diet with nutritional supplements can benefit your healthy lifestyle. The U.S. Food and Drug Administration has supported the use of calcium and vitamin D to help with osteoporosis, the use of folic acid supplements in pregnant women to reduce the risk of neural tube defects and fatty acid fish oils to reduce the risk of coronary heart dise