LUMC researchers: 'antioxidants do not reduce risk of heart attack'5 January 2021• PRESSRELEASE
LUMC scientists show in a study among 900,000 participants that antioxidants, such as vitamins A and E, do not reduce the risk of developing a heart attack. They conclude this after comparing the genetically-influenced antioxidant levels of healthy individuals with those of heart attack patients. The researchers describe their findings in the Journal of the American College of Cardiology.
"Based on our study, there is strong evidence that multivitamins with antioxidant activity do not have a beneficial effect on the risk of coronary heart disease," says epidemiologist Raymond Noordam. Noordam and colleagues draw this conclusion based on their study among 900,000 Europeans and Americans.
What are antioxidants?
Antioxidants trap harmful substances. These so-called reactive substances can cause damage to cells and DNA. "The idea is that the antioxidants like vitamins E and A capture these free substances which diminishes the damage caused by them. It is thought that less damage to cells and DNA leads to a lower risk of cardiovascular diseases," says Noordam.
Genetic antioxidant levels
"There was disagreement in the scientific literature about the effect of antioxidant supplements and antioxidant molecules on coronary heart disease," explains PhD student Jiao Luo. "Randomized clinical trials showed no effect while many observational studies did show a reduced risk.” The researchers therefore decided to investigate the relationship between antioxidants and the risk of heart attack using an alternative approach.
The researchers focused on the genetically-influenced levels of antioxidants in our blood. "Due to variation in our genetic make-up, some people have higher levels of antioxidants circulating in their blood", says Noordam. “We were able to collect this data from public datasets from the United Kingdom, United States and Finland, among other countries.”
“We subsequently compared the genetically-influenced antioxidant levels of a group consisting of healthy people with a group consisting of people who have had a heart attack", explains Lou.
Other heart diseases
Noordam concludes: "On the basis of our results, we can thus state that there is no evidence that vitamins with antioxidant properties should be used to prevent a heart attack. This large study therefore supports the clinical trials, and removes a lot of the controversy in the literature.” The next step is to investigate the alleged effects of antioxidants on other age-related diseases to provide recommendations for the use of antioxidants for any given indication.
Read the whole article in the Journal of the American College of Cardiology. This study was funded by the Dutch Heart Foundation and the Velux Foundation.