"Rich in antioxidants" is printed on everything from blueberries to breakfast cereal. But what are antioxidants, what do they actually do, and do you need to take them as a supplement? Here is a plain-English guide.
What are free radicals?
To understand antioxidants, start with what they work against. As your cells go about their normal work, they produce highly reactive molecules that contain oxygen, often called free radicals. They are reactive because they carry an unpaired electron and will take one from whatever is nearby, a bit like a single sock looking for its pair. Free radicals also come from outside sources such as cigarette smoke, air pollution and alcohol.
Your body uses some free radicals for normal functions, but when they are produced faster than the body can manage, the result is "oxidative stress." According to the NIH, oxidative stress may damage cells and contribute to chronic diseases such as heart disease and cancer.
What do antioxidants do?
Antioxidants help keep free radicals in check: the name literally means "against oxidants." Your body has its own defense system, and the NIH notes that the body's antioxidant enzymes are its most important part. Antioxidants from food may also help regulate oxidative stress. More is not always better, though: in large amounts, antioxidants can interfere with the cell's own defenses and normal signaling.
Where do antioxidants come from?
Your body makes some of the antioxidants it needs, and the rest come from food, mainly fruits, vegetables and whole grains. Common dietary antioxidants include:
- Vitamin C: citrus, berries, peppers, broccoli and kiwi
- Vitamin E: nuts, seeds and plant oils
- Carotenoids such as beta-carotene: carrots, sweet potatoes, leafy greens and other orange and dark green produce
- Polyphenols, including flavonoids: berries, tea, cocoa, apples, onions and spices such as turmeric
Eating plenty of these foods is linked to better health. A 2017 meta-analysis of 95 prospective studies found that people who ate more fruits and vegetables had lower risks of cardiovascular disease, cancer and early death, with the lowest risk at around 800 g a day, about ten servings.
Should you take antioxidant supplements?
Probably not in high doses, unless your doctor advises it. Studies of single antioxidant supplements have been disappointing. The NIH notes that, except for age-related macular degeneration, there is currently no evidence that antioxidant supplements help prevent the chronic diseases they have been studied for. A Cochrane review of 78 trials found no evidence that antioxidant supplements prevent death, and beta-carotene and vitamin E supplements appeared to increase mortality.
The likely explanation is that whole foods deliver hundreds of compounds working together, along with fiber and other nutrients, in amounts the body is used to handling. If you are considering a high-dose antioxidant supplement, talk to your doctor first, especially if you smoke or take medication.
Easy ways to get more antioxidants from food
- Fill half your plate with vegetables and fruit, and eat a range of colors.
- Snack on berries, nuts and seeds.
- Cook with herbs and spices, including turmeric. See the benefits of turmeric.
- Add a scoop of greens on busy days. Easy Being Green blends more than 20 organic greens and superfoods, which provide naturally occurring vitamins, minerals and antioxidants.
For more, read chronic inflammation: importance and prevention and what the research shows about chlorella.
