People who have coronary artery disease (CAD), or who are trying to avoid it, often ask their doctors whether dietary supplements could help. Unfortunately, research suggests that supplements -- that is vitamins, minerals, herbs, and certain food extracts -- can’t prevent or improve CAD, the most common type of heart disease. And, in some cases, these pills could hurt you.
“Patients a lot of times think, ‘Can I take this supplement so I don’t have to exercise or eat broccoli or fruits and vegetables?’” says Stephen Kopecky, MD, a preventive cardiologist and professor of medicine at Mayo Clinic in Rochester, MN. “And I’ll say: ‘There’s no supplement that takes the place of lifestyle [changes].’”
What Do Top Expert Groups Say About Supplements?
To lower your chances for heart disease, the American Heart Association advises healthy people to get their nutrition from a balanced diet, not supplements.
The U.S. Preventive Services Task Force (USPSTF), a panel of experts in disease prevention and evidence-based medicine, says there’s not enough evidence to recommend for or against taking vitamin and mineral supplements to prevent heart disease.
“There have been a lot of studies in this area, but they’ve all shown that there’s no cardiovascular benefit from supplements, and in some cases they cause harm,” says Erin Donnelly Michos, MD, a cardiologist and associate professor at Johns Hopkins School of Medicine in Baltimore.
What Are the Risks of Taking Supplements?
For one thing, it’s possible that a supplement could interfere with medications you’re taking for coronary artery disease or other health conditions. For example, if you take fish oil supplements while you’re on blood thinning medication, the combination could raise your risk for dangerous bleeding, Michos says.
That’s why it’s important to tell your doctor about any supplements -- including vitamins -- you’re already using, so they can check for possible interactions and side effects, she says. Always talk to your doctor before you try a new supplement.
Another risk of supplements is that some of them could raise your chances for other unintended health consequences. For example, in people who take calcium supplements, some but not all studies have shown a higher risk for heart attack, Michos says. A review of studies that she worked on also found an increased risk for stroke in people who took calcium with vitamin D supplements. Calcium-rich foods, on the other hand, don’t seem to come with any of these risks, she says.
The quality of supplements varies, too. The FDA doesn’t regulate supplements as tightly as it does drugs. The agency doesn’t review supplements for safety before they go on sale. It treats them more like food.
Instead, it’s up to supplement makers and distributors to make sure their products are safe before they sell them. It isn’t until a supplement proves to be unsafe that authorities take it off the market, Michos says. That means there’s a chance that a supplement could contain ingredients not listed on the label, be contaminated, or contain a stronger or weaker dose of the active ingredient than the label says it does.
“[Supplements] aren’t inspected by the FDA, so we’re not really sure what’s in a lot of them, especially ones from other countries,” Kopecky says.
The FDA also does not test supplements for effectiveness. If you’ve heard or read that a certain supplement might help prevent coronary artery disease, there’s probably not a lot of scientific evidence to back that up. In fact, federal law prohibits that dietary supplement labels claim that a product treats, prevents, or cures a disease.
Can Fish Oil Supplements Do Your Heart Good?
Some kinds of fish -- like salmon, sardines, and cod -- have heart-healthy fats in them called omega-3s. Many people with heart disease ask if fish oil supplements could help them, Kopecky says.
But, he says, over-the-counter fish oil supplements “[haven’t] been shown to consistently make a difference” against coronary disease. And higher doses of prescription fish oil have been linked to a type of irregular heartbeat called atrial fibrillation.
Still, the American Heart Association says fish oil supplements might be worth considering for some people with heart disease who don’t get enough omega-3s from food. But they should talk to their doctor first to check for interactions and weigh the pros and cons.
Is a Healthy Diet More Important Than Supplements?
Absolutely. If you’re living with coronary artery disease or trying to prevent it, focus on eating a variety of nutritious foods, experts say.
There’s nothing healthier than eating a minimally processed, heart-healthy diet, Michos says. She recommends the Mediterranean or DASH diet. Both emphasize foods like fruit, veggies, fish, and whole grains, while limiting things like refined carbs, sweet drinks, and processed meats. If you don’t eat meat, a healthy plant-based diet would fit the bill, too.
Americans get too many of their calories from ultra-processed foods, Kopecky says. “Those are the things like ‘open and eat,’ ‘ready to eat,’ ‘heat and eat’ stuff,” he says.
If your diet isn’t healthy now, there’s no need to overhaul it in a day. “It’s better to do small, sustained changes that you can live with for a long time,” Kopecky says.
“Even minor changes in diet have been shown to be helpful,” he says. “Meaning, if you take one bite of processed meat and replace that on your plate with one bite of something that we know is better for you … then after a couple years that actually reduces your risk of a heart attack. So, little things.”
If you need some extra help changing your eating habits, you could ask your doctor to refer you to a dietitian.