- A review of nearly 900 clinical trials found evidence supporting taking folic acid and fish oil for heart health.
- Vitamin C, vitamin D, and vitamin E had no effect on heart disease.
- But tell your doctor about any supplements you’re on, per new guidance from the American Heart Association.
A new review of nearly 900 clinical trials identified supplements can support heart health — and the ones that either don’t help or could cause harm.
The review, which looked at trials for 27 types of micronutrients, is the first to categorize micronutrient supplements by their effect on heart health based on current trial data. It was published in the Journal of the American College of Cardiology (JACC) on December 5.
The review identified three supplements that have the best quality evidence supporting their positive effect on heart health: omega-3 fatty acids, or fish oil, decreased death from heart disease; folic acid decreased stroke risk; and the antioxidant coenzyme Q10 decreased mortality.
One supplement had harmful health effects. Beta carotene, which converts to vitamin A in our bodies, supplement use increased the risk of death from heart disease. The findings are in line with the US Preventive Services Task Force’s (USPSTF) guidance not to take vitamin A supplements without consulting a doctor due to the risk of toxicity, which can lead to muscle and bone pain, nausea, and hair loss.
Vitamin C, vitamin D, vitamin E, and selenium had no effect on heart disease or diabetes risk.
Simin Liu, an epidemiologist at Brown University and an author on the study, said in a press release the findings can be used to inform future clinical trials studying how micronutrients effect heart health. The study indicates supplementation could help with heart health, but more research is needed on how they work.
“Identifying the optimal mixture of micronutrients is important, as not all are beneficial, and some may even have harmful effects,” Liu said in the release.
Research on supplements and heart health has shown mixed efficacy
Though some doctors prescribe fish oil and other supplements to help heart health, studies on these supplements have shown mixed results.
For instance, a recent study found fish oil supplements won’t lower a person’s levels of “bad” cholesterol that’s associated with heart disease and stroke, but another large report found the supplement significantly reduced a person’s risk of heart attack.
Previous research has found folic acid may lower stroke risk. The National Institutes of Health recommends people who are pregnant or want to become pregnant take folic acid, as the supplement has been shown to decrease birth defects.
If you decide to take supplements, tell your heart doctor. The American Heart Association recently issued a scientific statement urging doctors and patients to talk about supplements with each other as cardiologists say they are noticing a rise in heart problems associated with herbal remedies.
“Although many [complementary and alternative medicines] are purported to be efficacious and safe by the public, clinical evidence supporting the use of [complementary and alternative medicines] in heart failure remains limited and controversial,” the AHA stated.