It’s not hard to find food and drinks in the grocery store as being touted as “rich in antioxidants.” Blueberries, green tea, you know the drill. The underlying message is clear: foods containing antioxidants are better for your overall health. Even red wine and chocolate are sometimes touted for this supposed nutritional benefit. But what are antioxidants, exactly? And do they actually make wine good for you?
At the most basic level, antioxidants are tiny chemical compounds that neutralize free radicals, unstable molecules produced within the body that can damage cells. Free radicals are thought to play a role in several chronic conditions, including heart disease, diabetes, and cancer. A wide variety of vitamins, minerals, and other substances—including C and E, zinc, selenium, beta-carotenes, lutein, and more—serve as antioxidants, and are routinely highlighted on food packaging and hawked as supplements. A diet rich in antioxidants, therefore, should help delay or even prevent disease. Right?
Well, before you start guzzling chocolate syrup and housing vitamin E pills, here are some antioxidant basics to consider.
The Radical Truth
The 1990s were wild times: Flannel was high fashion and antioxidants suddenly got sexy. The main reason comes back to the relationship between antioxidants and free radicals. Free radicals are oxygen-containing molecules that are formed during natural processes: The body produces them as it converts food into energy. You also produce them during exercise as well as a result of environmental exposure to things like sunlight and tobacco smoke.
The “radical” refers to the basic chemistry of these molecules—free radicals are unstable because they have an uneven number of electrons. Through oxidation, free radicals react with other molecules in the body by stealing their electrons. For the most part, this is normal, and even beneficial in some circumstances. (For instance, free radicals are generated by the immune system as it begins to fight invaders help destroy viruses.)
Too many free radicals in the body, however, lead to a state oxidative stress. Left unchecked, free radicals will chew up proteins, lipids, pieces of DNA, cell membranes—pretty much anything that ensures the body’s cells are healthy and performing adequately. If you’re looking for the appropriate metaphor, bite into an apple and let it sit in the sun for a few minutes: The insides of that juicy Golden Delicious will undoubtedly oxidize and turn an unappetizing brown color. Now imagine that happening inside your body.
Enter the humble antioxidant. We extract these from foods, and they’re powerful free-radical fighters because they willingly surrender some of their own electrons to free radicals. A balance of free radicals and antioxidants in the body keeps oxidative stress in check. During the Clinton years, scientists began to link free-radical damage to the initial stages of atherosclerosis and a few other chronic diseases. Some studies showed that people who ate fewer antioxidant-rich fruits and vegetables were at a greater risk of developing these diseases. Subsequently there was a push to not only better understand antioxidants, but also to figure out whether supplemental forms of antioxidants would stave off chronic disease.
Supplement Your Diet (But Not With Supplements)
A bunch of studies measuring the effects of antioxidants delivered via supplement delivered, well, mixed results. Clinical trials of beta-carotenes sponsored by the National Institutes of Health and completed in the 1990s showed no protection against heart disease or cancer. Another, later study, this time of vitamins E and C, found no reduction in “major cardiovascular events” like heart attack or stroke in 14,000 physicians aged 50 and older. (The National Center for Complementary and Integrative Health has a good rundown of all the studies and what they found.)
So what gives? It’s important to note that the term antioxidant, as the Harvard Medical School points out, “reflects a chemical property rather than a specific nutritional property.” They act as electron donors in their quest to neutralize free radicals. In other words, you can’t gorge yourself on the things. And products labeled as “antioxidant-rich,” as if antioxidants are some specific nutrient that were added to them, are misleading at best.
But many foods contain the antioxidants—the vitamins, zinc, beta-carotenes, flavonoids, and other substances—that are beneficial to your health. So instead of popping milligrams upon milligrams of supplements, prioritize eating fruits, vegetables, and whole grains. Broccoli and leafy greens are good sources of vitamin C. Chicken has lots of zinc. Almonds and avocado provide vitamin E, while, yes, berries and green tea contain polyphenols—a fancy word for plant chemicals—that act as antioxidants.
It’s kind of a boring answer, but like so many nutritional questions, eating a varied diet of fruits, vegetables, whole grains, and lean protein is ultimately your best source of antioxidant protection. Chocolate and pinot noir in moderation never killed anyone, but don’t go looking for any nutritional bonus points.