antioxidants 101

Written by Gloria Tsang, RDPublished in Dec 2005; Updated in Aug 2007
What are Antioxidants? Benefits of Antioxidants
Antioxidants are substances or nutrients in our foods which can prevent or slow the oxidative damage to our body. When our body cells use oxygen, they naturally produce free radicals (by-products) which can cause damage. Antioxidants act as "free radical scavengers" and hence prevent and repair damage done by these free radicals. Health problems such as heart disease, macular degeneration, diabetes, cancer etc are all contributed by oxidative damage. Indeed, a recent study conducted by researchers from London found that 5 servings of fruits and vegetables reduce the risk of stroke by 25 percent. Antioxidants may also enhance immune defense and therefore lower the risk of cancer and infection.
Most Commonly Known Antioxidants

Vitamin A and Carotenoids
Carrots, squash, broccoli, sweet potatoes, tomatoes, kale, collards, cantaloupe, peaches and apricots (bright-colored fruits and vegetables!)

Vitamin C
Citrus fruits like oranges and lime etc, green peppers, broccoli, green leafy vegetables, strawberries and tomatoes

Vitamin E
Nuts & seeds, whole grains, green leafy vegetables, vegetable oil and liver oil

Selenium
Fish & shellfish, red meat, grains, eggs, chicken and garlic
Other Common Antioxidants
Some common phytochemicals
Flavonoids / polyphenols
soy
red wine
purple grapes or Concord grapes
pomegranate
cranberries
tea
Lycopene
Tomato and tomato products
pink grapefruit
watermelon
Lutein
dark green vegetables such as kale, broccoli, kiwi, brussels sprout and spinach
Lignan
flax seed
oatmeal
barley
rye
Vitamin-like Antioxidants:
Coenzyme Q10 (CoQ10)
Glutathione
Antioxidant enzymes made by the body:
superoxide dismutase (SOD)
catalase
glutathione peroxidase
Message: Antioxidants are found abundant in beans, grain products, fruits and vegetables. Look for fruits with bright color - lutein in some of the yellow pigments found in corn; orange in cantaloupe, butternut squash and mango; red from lycopene in tomatoes and watermelon, and purple and blue in berries. So enjoy eating a variety of these products. It is best to obtain these antioxidants from foods instead of supplements. In addition, minimize the exposure of oxidative stress such as smoking and sunburn.