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A handful of food-based substances supply antioxidants to the body. The following are powerful antioxidants found in food:

• Beta-carotene and other carotenoids. Carotenoids are the pigments in plants that typically cause fruits and vegetables to appear red, orange or deep yellow. Some foods that are dark green also contain carotenoids that are hidden by the green of the plant’s chlorophyll (the chemical that facilitates photosynthesis, the process by which plants convert sunlight into chemical energy). It should be noted that food color is not always a good indicator of antioxidant levels. For example, corn is deep yellow yet does not contain a high level of carotenoids.
  
  Beta-carotene is the most common carotenoid to appear in foods. It is converted into vitamin A in the body. Other carotenoids found in fruits and vegetables include alpha-carotene, beta-cryptoxanthin, lycopene, lutein and zeaxanthin. Because carotenoids are fat-soluble, they may be stored in the body and help fight free radicals in lipids and fat tissues.
  
  
• Vitamin C. As an antioxidant, vitamin C may protect the body in a fashion similar to beta-carotene. However, vitamin C helps remove free radicals from body fluids (e.g., blood) rather than from fat tissue. It also neutralizes free radicals created from polluted air and cigarette smoke. Research is under way to determine whether vitamin C’s antioxidant properties may help reduce the risk of cancer and cataracts (clouding of the eye lens).
  
  
• Vitamin E. Many health benefits have been claimed on behalf of this vitamin, not all of which have turned out to be true. However, vitamin E does appear to offer many benefits as an antioxidant. It may help to prevent the oxidation of low-density lipoprotein (LDL) cholesterol – the so-called “bad” cholesterol that causes plaque buildup in the arteries – and cell membranes by stopping the free-radical chain reaction process. It also may help prevent some cancers. Vitamin E works together with antioxidants such as vitamin C to prevent other chronic diseases.
  
  
  

  

  
  
• Selenium. An essential trace mineral in the human body and an important part of antioxidant enzymes that protect against the effects of free radicals. Selenium works with vitamin E to protect cells from damage. The amount of selenium found in foods is directly related to the amount of selenium in the soil in which the food was grown. Some studies indicate that selenium may reduce the risk of cancer, particularly lung, prostate, and colorectal cancers.
  

Certain enzymes in the body also serve as antioxidants. So do phytonutrients such as flavonoids, which also prevent oxidation of LDL cholesterol, reduce the stickiness of blood platelets and protect against various diseases.