A new study on multivitamins and heart health reinforces what medical experts have been saying for years: They don’t do much to prevent cardiovascular disease.

The report is a meta-analysis of previous research. It looked at 18 different studies that spanned more than 16 years. In all, about 2 million people were involved. In some of the studies, the participants were followed for 12 years.

Researchers from the University of Alabama at Birmingham (UAB) published their report in the journal Circulation: Cardiovascular Quality and Outcomes. The authors say their report confirms previous findings on the role that vitamins play in improving heart health.

Who needs multivitamins?

The general concept that multivitamins and supplements in the form of pills are beneficial to your health isn’t wrong per se. For example, pregnant women, children, and specific adult populations, such as people with cancer, should take certain types of vitamins. At issue here is whether multivitamins can reduce the risk of cardiovascular disease.

“I hope our study findings help decrease the hype around multivitamin and mineral supplements and encourage people to use proven methods to reduce their risk of cardiovascular diseases,” said study lead author Dr. Joonseok Kim, assistant professor of medicine/cardiology in the Department of Medicine at UAB, in a press release.

So what should you do to stay healthy?

The best defense for good heart health is a healthy lifestyle, according to Dr. Stephen Kopecky, a cardiologist at the Mayo Clinic in Rochester, Minnesota. That includes consistent exercise, adequate sleep, and a diet that relies on whole foods, with an emphasis on fruits and vegetable.

The misperception that multivitamins can mitigate unhealthy eating, in particular, continues to exist in the public consciousness. Kopecky hopes this new meta-analysis can better educate the public about multivitamins and heart heath.

“I’m in full agreement with the study,” he told Healthline.

Kopecky said the reason people view multivitamins and supplements as a means to improve their heart health is simple — people want convenience.

“We want to take a pill that will negate our lifestyle shortcomings,” Kopecky said.

Dr. Zhaoping Li, director at the UCLA Center for Human Nutrition, agrees. She said someone who has heart disease but still has a sedentary lifestyle, and a diet filled with lots of fat, salt, and sugar, won’t see an improvement in their heart health because they take a daily multivitamin.

“I’m not sure vitamins are going to reverse that,” she told Healthline.

There is one exception that both Kopecky and Li point to. In the instance of cardiovascular disease, they do support taking omega-3 fatty acids in the form of fish oil supplements.

This type of unsaturated fatty acid may decrease triglycerides, lower blood pressure, reduce blood clotting, decrease the risk for stroke and heart failure, and reduce irregular heartbeats.

This new report didn’t focus on studies that included fish oil. It only looked at the studies that revolved around multivitamins, vitamins D and C, and calcium. It’s not the first time a study has shown multivitamins don’t improve heart health.

Past evidence on multivitamins

A 2012 study on nearly 2,000 men showed no evidence that a daily multivitamin could reduce a major cardiovascular event. A U.S. taskforce also said there is insufficient evidence to conclude that multivitamins can prevent cardiovascular disease and cancer.

Even the country’s leading health institutions such as the Mayo Clinic and Johns Hopkins Hospital have devoted pages on their websites to dispute the notion that multivitamins can boost heart health. But despite the attempts of medical organizations and the U.S. government to counter this misinformation, their words continue to go unheeded.

Around 76 percent of Americans take a dietary supplements, according to a 2017 survey by the Council for Responsible Nutrition. Roughly 42 percent said they were taking supplements for overall health and about 26 percent said it was to improve heart health. According to the National Institutes of Health (NIH), in 2014 Americans spent $36.7 billion on dietary supplements, of which $5.7 billion dollars went toward multivitamins.

The multivitamin and supplement industry is regulated by the Dietary Supplement Health and Education Act passed by Congress in 1994. The FDA is the governing body. The act states that makers can’t make a claim that specific supplements can reduce pain or improve heart health, according to the agency’s website.

However, the act doesn’t require manufacturers to demonstrate the safety of a given supplement before bringing it to market. Additionally, the FDA can only ban a supplement if it finds proof that it’s dangerous.

Both Kopecky and Li said they usually don’t encourage their patients to take multivitamins. The only exception for both doctors is if a patient with heart disease has difficulty making their diet nutritionally diverse.

“If they’re already healthy, I don’t necessarily,” Li said. “For people who don’t take in adequate fruits and vegetables, I do recommend it.”

Kopecky noted that he does take the time to consult his patients about the importance diet plays in their overall health. He encourages his patients to eat oat bran in the form of oatmeal, which has been proven to lower cholesterol. He also recommends his patients take a daily dose of soluble fiber, which also helps to keep cholesterol from getting absorbed into the blood stream. But Kopecky added that the hard part is making all of the information stick.

“It’s hard to meet someone and in 20 or 30 minutes change their lifestyle,” he said.