Antioxidants "soak up" free radicals. They do this by neutralizing the free radicals' electronic charge. Left as they are, free radicals harm your body, making cells less stable. In that way, free radicals "age" the body. Free radicals may even play a role in different disorders -- from Alzheimer's to cataracts. Antioxidants fight free radicals to keep these damaging substances out of your body as much as possible.
Free Radicals
Free radicals react easily with other molecules in the body because they consist of unpaired electrons. Think of each unpaired electron as a sticky end ready to connect with another substance. Because of their reactive nature, free radicals can cause damage to cells in the body by reacting with molecules in cell membranes. Oxygen-based free radicals cause the most harm. However, these molecules come from a wide range of sources -- from fried foods to air pollutants. Even your own metabolic processes create some free radicals.
Antioxidants
The term "antioxidants" applies to a whole range of substances, including some vitamins and minerals. These substances neutralize free radicals from the body. Your body produces antioxidants, but you can also increase the amount in your system through the food you eat. Antioxidants include vitamin C and the mineral selenium. However, according to the Human Nutrition Research Center on Aging at Tufts University, two of the most powerful antioxidants are the flavonoids and carotenoids. These occur in foods as diverse as dark chocolate and carrots.
Process
Antioxidants fight free radicals by giving up their own electrons. This process neutralizes the free radical molecule. As the free radical passes through the body, it no longer tries to pair or bond with molecules in cell membranes, so that the cells remain undamaged. Unlike free radicals, when an antioxidant molecule loses an electron, it doesn't try to scavenge electrons from surrounding molecules in body cells. This makes it a benign and unreactive substance.
Considerations
Different antioxidants help fight different forms of free radicals. No single "miracle antioxidant" exists, despite the claims of some health food companies. This is one reason why you should eat several different types and colors of fruits and vegetables. For example, orange vegetables such as carrots tend to contain carotenoids. Lutein, on the other hand, occurs in high concentrations in dark green leafy vegetables such as spinach. This approach gives you the broadest range of antioxidants with which to fight free radicals.
References
- Huntingdon's Outreach Project for Education at Stanford; About Free Radical Damage; E. Tan; January 21, 2001
- Hypertexts of Biomedical Sciences at Colorado State University; Free Radicals and Reactive Oxygen; R. Bowen; August 16, 2003
- Harvard School of Public Health: Antioxidants: Beyond the Hype
- Tufts University Human Nutrition Research Center on Aging: Antioxidants
- Health Services at Columbia; Antioxidants; April 25, 2008
