What are antioxidants? Why do we need them?

Antioxidants are molecules that can prevent the oxidation of other molecules and the resulting free radicals that are produced. Antioxidants can help protect the body against such things as cancer, heart disease, arthritis, cataracts, allergies, diabetes, auto-immune diseases, chronic physical stress, environmental toxins, as well as help slow the aging process. The best-known and well-researched antioxidant nutrients are: vitamin C, vitamin E, carotene’s, lipoic acid, selenium, and zinc. Less researched but known to be supportive are bioflavonoids, manganese, and copper.

What are free radicals?

Free radicals are unstable and highly reactive molecules. Our body needs antioxidants to bind free radicals, thus making them less reactive and less damaging to our cells, tissues, and organs. If they can’t find antioxidants to bind to, free radicals will react with any nearby cell or compound in the body. In doing so, they not only damage cellular membranes and genetic material (DNA, RNA) by making them less functional; they may also form another radical in the process. This starts a cascade of events that may lead to chronic illness and disease if excess free radicals accumulate.

Where do free radicals come from?

The majority of free radicals come from the body’s normal day to day activities, such as chemical reactions to build cells and detoxification of drugs and wastes in the liver. Free radicals can also be byproducts of heavy exercise and food digestion. In a beneficial way, the body’s immune system also forms free radicals to destroy bacteria and viruses when attempting to fight infections. They are used to patrol the blood and tissues for cancer cells and other invaders. Other sources of free radicals are encountered when our body’s are exposed to toxins and foreign materials in the environment (air, water, foods, beverages, etc.).

What are environmental sources that can result in free radicals?

Air pollution, tobacco smoke (secondary and primary), excessive radiation, sunlight, X-rays, herbicides, pesticides, fumigants, anesthetics, drugs, aromatic hydrocarbons (petroleum based products) often used to extract oils, and solvents such as formaldehyde, toluene and benzene found in cleaning fluids, paints and furniture polish. A large part of our toxic waste is polypropylene from plastic packaging and containers, used in the food supply.

What are dietary sources that can result in free radicals?

Dietary sources that can result in free redicals include trans fatty acids in fried (especially deep-fried) foods; partially hydrogenated oils in products like margarine, shortening, potato chips, mayonnaise, some salad dressings, processed and packaged pastries; and nitrosamines in foods that are barbecued, charbroiled, or cured/smoked such as hotdogs and luncheon meats. At high levels, problems can also arise from food additives, preservatives, dyes, and plastic or aluminum migrants from food containers. Alcohol may also contribute.

How do we reduce free radical damage?

Eat a diet rich in antioxidants (see ideas listed below) by including fresh, local, and organic produce daily. Consumption of fresh, local and organic foods will reduce your exposure to environmental toxins (the ones that result in free radical production), and will provide quality nutrients.

MAJOR ANTIOXIDANT NUTRIENTS AND THEIR DIETARY SOURCES

Carotene(s)
broccoli, cantaloupe, carrots (and juice), fresh or dried apricots, mangoes and persimmon, leafy greens (spinach, kale, mustard, collard, swiss chard), pumpkin, winter squash, sweet potatoes, tomato products

Vitamin C
blackberries, raspberries, strawberries, citrus fruits and juices (oranges and grapefruits) cruciferous vegetables (broccoli, cauliflower, brussels sprouts, kohlrabi, cabbage), leafy greens (mustard, turnip, kale, collard), melons (especially cantaloupe), papaya, kiwi, mangoes, pineapple, guava, strawberries, red and green peppers, sweet potatoes, tomatoes and tomato juice

Bioflavonoids
apples, green tea, onions, cherries, blueberries, herbs; bilberry, hawthorn, chamomile, ginkgo, milk thistle, quercitin, and from white fleshy portion of orange peel or green pepper

Vitamin E
avocados, fish and shellfish, leafy greens (fresh spinach, kale, collard), mangoes, nuts, seeds, wheat germ, whole grain products, vegetable oils, egg yolk

Selenium
cashews, eggs, garlic, halibut, oysters, salmon, tuna, scallops

Zinc
oysters, crabmeat, cheese, beef roast, pumpkin seeds and cashews – dry roasted, whole grains (germ/bran)

References:
1. Levin, Buck Ph.D., RD, Environmental Nutrition, 1999, HingePin Integrative Learning Materials, Vashon Island, WA
2. Marz, Russell B, ND, M.Ac.O.M. Medical Nutrition From Marz, 2nd Ed. 1999, Omni-Press, Portland OR
3. Schmidt, Michael A., Smart Fats, 1997, Frog Ltd. Berkley CA
4. Groff JL, Gropper SS, Advanced Nutrition and Human Metabolism, 3rd Ed. 2000 Wadsworth Publ.
5. Brown, Donald J. ND, Herbal Prescriptions for Health and Healing, 2000, Prima Health Publ., CA
6. Pennington, Jean AT, Ph.D., RD, Bowes & Church’s Food Values of Portions Commonly Used, 1988, 7th Ed., Lippincott Publ., NY
7. Champe, Pamela C., Harvey, Richard A., Biochemistry, 2nd Ed. 1994, Lippincott-Raven Publ., PA