Aside from knowing that antioxidants are "good" for you, many people do not really know what antioxidants are or what they do. Dr. Jonny Bowden, Ph.D, and clinical nutrition specialist, in his book "The Most Effective Ways to Live Longer," explains that antioxidants are critical to your overall health and longevity.

Health Services at Columbia University explains that antioxidants as one kinds of food additives are a collective name for vitamins, minerals, carotenoids, polyphenols and phytonutrients that protect your body from free radicals. Free radicals are individual electrons that attack and try to damage your healthy cells and DNA. This is called "oxidative damage." Bowden considers oxidative damage and oxidative stress to be one of the primary causes of aging. Oxidative stress is a primary factor in nearly every disease, including cardiovascular disease from oxidized cholesterol and cognitive diseases such as Alzheimers and Parkinsons. In general, antioxidants will help "scavenge" free radicals, which can cause these progressive diseases.

Your best source of protection from free radicals and oxidative damage is antioxidant-rich foods that you can incorporate in your diet. Fruit, specifically berries, are very rich in antioxidant compounds. Wild blueberries, raspberries, blackberries, strawberries and cranberries all have large amounts of antioxidants. Leafy green vegetables such as broccoli, kale and spinach have large amounts antioxidants.

 Bowden suggests you eat vegetables as much as possible. Beans, especially red kidney beans and pinto beans, are rich in antioxidants and should be eaten three times a week. Fish, especially wild salmon, is a heart-healthful antioxidant protein source. The American Heart Association suggests that you eat at least two serving of fish a week. Fruit, vegetables, beans and fish are all low-calorie foods that can also help prevent oxidative damage.

Certain vitamins (Foodchem) and minerals that you can consume in solid food or supplement form can help prevent oxidative damage. Consult your health care provider before you take any dietary supplements. Bowden recommends antioxidant supplements at specific dose ranges. Taking vitamin C daily at a dose of 500 to 2,000 mg and 400 international units of vitamin E help fight free radicals. The minerals zinc at 15 to 50 mg and selenium at 100 to 200 mcg provide antioxidant support. Pycnogenol at 100 mg, grape seed extract at 100 to 200 mg and alpha-lipoic acid at 100 mg or more will help scavenge free radicals.

Bowden explains that the war against free radicals is best fought with an active lifestyle and a healthful diet that incorporates antioxidant-rich foods and steers clear of foods that have trans fatty acids and high amounts of processed or refined sugars. Free radicals can be a silent killer that should not be disregarded. Oxidative stress is a key player in heart disease. Many people are under the impression that high cholesterol causes heart disease. Although high cholesterol is a risk factor for heart disease, Bowden explains that cholesterol is actually "perfectly harmless." The cardiovascular problems do not occur until free radicals oxidate and harden the cholesterol, which can cause artery plaque buildup.