All About Antioxidants

A war is being waged inside your body. It’s a biological power struggle that takes place in every air-breathing creature, and only good nutrition and a healthy lifestyle can help you win battles.

The bad guys are free radicals – highly reactive chemicals that damage body tissues by pilfering electrons in a ruthless quest to improve their own stability. The good guys are antioxidants – chemicals that either prevent or halt free radical damage, often by “donating” electrons to them.

The most common and potent kind of free radical is plain old oxygen, and so a certain amount of “oxidative stress” is as inevitable as breathing, unfortunately. Sources of other free radical types include herbicides and pesticides, alcohol, air pollutants (including cigarette smoke), ultraviolet light, and even many forms of stress.

Over time, free radical accumulation can cause big health problems. “There is evidence that free radicals are a predominant factor in the etiology of a very wide range of diseases and conditions such as cancer, diabetes, atherosclerosis, Alzheimer’s disease, and rheumatoid arthritis,” says Li Li Ji, Ph.D., an expert on free radicals and antioxidants at the University of Wisconsin. Even aging itself may be primarily an effect of free radical damage, many scientists believe.

Fortunately, you can call upon literally dozens of different antioxidants to control the radicals. Some antioxidants are enzymes produced by the body, while others are nutrients that come from the diet. “Each antioxidant is specialized in one job,” says Ji. “They’re good at one thing.” Here’s a sampling of organs and tissues that are known to receive protection from specific antioxidants.

Derived from the leaves of the world’s oldest known tree species, ginkgo biloba has antioxidant properties that are believed to combat oxidative stress in the brain and the conditions associated with it (including Alzheimer’s disease). Recommended intake: 120 mg per day appears to be a safe and effective amount.

Lutein belongs to the carotenoids class of phytochemicals (plant nutrients). Broccoli, oranges, and green leafy vegetables such as spinach and collard greens are rich in lutein, which is also the antioxidant found in the highest concentration in the eyes. There’s a strong correlation between lutein deficiency in the eyes and age-related macular degeneration. Recommended intake: If you eat a balance of five fruits and vegetables a day, you’ll get plenty of lutein and have no need to supplement.

Coenzyme Q10 (or CoQ10) is produced within the body and aids in turning food into energy fuel. It exists in every cell, but is most concentrated in the heart, which it protects from free radicals. It has the proven ability to lower blood pressure and lessen the risk of heart disease. Taking a synthetic CoQ10 supplement is not a bad idea for those with high blood pressure or other cardiovascular risk factors, but ask your doctor first. Recommended intake: Most commercial supplements recommend doses of 30 to 90 mg daily.

Vitamin C is the lungs’ main antioxidant. Individuals who consume higher levels of vitamin C, which is abundant in citrus fruits and many vegetables, have a lower risk of pulmonary disease. Recommended intake: 90 to 2,000 mg per day.

Some of the muscle soreness you feel the day after a hard workout is due to free radical damage. Several studies have shown that vitamin E helps reduce exercise-induced free radical damage to muscle cells. Good sources of vitamin E include vegetable oils, nuts, dark green vegetables, and whole grains. Recommended intake: 15 to 1,000 mg per day. Serious athletes should try to get close to the maximum allowance.

The sulfur compounds contained in garlic exhibit powerful antioxidant properties that protect many parts of the body from oxidative stress, but the stomach may receive the most benefit. One scientific review suggests that garlic reduces the risk of stomach cancer by 50 percent. Recommended intake: between one-half and one clove of fresh garlic per day.

The compound silymarin, found in the seeds of the milk thistle flower, appears to defend the liver against free radicals and associated diseases such as cirrhosis. A variety of supplements manufacturers offer milk thistle’s active ingredient in pill form. Recommended intake: It is generally not necessary to take a silymarin supplement, but a daily intake of 420 mg per day has proven to be safe and effective.

Another carotenoid called lycopene is the prostate’s most trusted antioxidant. Watermelon, guava, and especially tomatoes are rich in lycopene. Men who eat tomatoes at least twice a week have a 24- to 36% lower risk of prostate cancer than those who eat tomatoes less often. Recommended intake: eat tomatoes at least twice a week.

There’s nothing worse than a messy colon. To keep yours in order, eat plenty of berries, which are rich in antioxidants called anthocyanins. Black raspberries, in particular, have demonstrated powerful anti-tumor effects. Recommended intake: eat a serving of fresh or frozen berries at least twice a week.

The list of known antioxidants is hundreds long, and growing constantly. In order to maximize your health, you need to memorize all of them, learn which foods they’re present in, and make sure you eat them every day. Just kidding. “It’s very difficult and also completely unnecessary to design a menu based on antioxidant needs,” says Alex Sevanian, Ph.D. “If we just follow some simple guidelines, we can get all the nutrition we need without becoming confused or neurotic.

1. Eat everything. “The simplest way to ensure that you get the widest possible range of antioxidants, and other nutrients, is to maintain a very broad diet,” says Sevanian.

2. Don’t eat too much of anything. “The essence of health is balance,” pronounces Sevanian. “Overeating any kind of food or nutrient, including particular antioxidants, is not good for the body.”

3. Minimize processed foods. According to Sevanian, processed foods such as refined grains generally contain the smallest amounts of antioxidants and other nutrients per calorie and should therefore represent a small portion of your diet.

4. Supplement with caution. “Most antioxidants work in combination with other antioxidants, and for this reason taking individual antioxidant supplements is not as good as getting them from foods,” explains Sevanian. “Supplementation is only necessary in cases of specific deficiencies or health conditions.”


It’s true: due to the high rate of oxygen consumption associated with exercise, working out generates more free radicals than sitting on the couch and watching sitcoms. However, if you follow these tips, you can train your way to stronger antioxidant defenses and less oxidative stress than your pudgy neighbor has.

1. Train progressively. “As a mild form of stress, exercise enhances the body’s ability to handle stress more than it harms the body through stress,” says Sevanian. “If you build your fitness level gradually, your body’s antioxidant defenses will always improve faster than free radical generation increases.”

2. Don’t get inflamed. According to Wisconsin’s Ji, tissue inflammation – a common side effect of exercise stress – is a major source of free radicals. Avoid inflammation by using proper technique and by warming up before and cooling down after workouts. Quickly treat any swelling that does occur with ice and anti-inflammatory medication.

3. Flee the smog. The high breathing rate involved in exercising greatly compounds the free radical damage caused by inhaling polluted air. Do not exercise outdoors in smoggy environments.

4. Pound C and E. “People who are involved in rigorous exercise consume more antioxidants,” says Ji, “so they need to take in more. Getting extra vitamin E, either through foods or supplementation, is especially important.”

5. Drink “Antioxidant-ade”. According to Ji, there is some evidence that an acute dose of antioxidants taken immediately before and after workouts can reduce exercise-generated oxidative stress. Therefore, he says, “I think it’s advisable to use a sports drink with antioxidants.”