Wanted: The Free Radical

If you've never heard of a free radical, you will before long. Today more and more medical researchers are saying that, if present in excess, they may harm your body in numerous ways.

Free radicals aren't escaped political prisoners. They are highly reactive molecules with some unusual traits. They are able to damage your body (at a cellular level) through a process called oxidation. A familiar form of oxidation is the rusting of steel. Oxidation, it seems, can be bad for both car bodies and human bodies.

Oxidation, possibly caused by an overabundance of free radicals, contributes to hardening of the arteries (atherosclerosis) and damage to DNA, the genetic material of the cell.

Free radicals,by damaging DNA, may be linked to cancer. Several kinds of cancer, including lung and stomach cancer, appear to be caused by the damage cells suffer when their genetic material is oxidized.

Even aging itself may be connected to free radicals. One theory is that the general oxidization of body tissues over the years may produce the slow decay in health we call getting old. Researchers also are studying whether cataracts, another condition associated with aging, may be partially caused by the action of free radicals.

A fountain of free radicals

Maybe the reason that nobody escapes getting old is that we live -- not in a fountain of youth -- but in a fountain of free radicals. Free radicals are all around us. Cigarette and other kinds of smoke and various chemicals create them in hordes.

We're bathed in free radicals inside, too. The biggest source of free radicals in your body is your own metabolism. Every time your cells turn food into energy, the process creates free radicals.

Your body doesn't leave you to face free radicals unarmed, however. It builds powerful lines of defense in the form of enzymes that neutralize radicals on contact.

Still, plenty of radicals may escape the body's built-in defenses. Luckily, it turns out that vitamins A, C, and E, and some phytochemicals are very good at preventing the molecules of your body from oxidizing. That's why they're called "antioxidants."

You can load up on these antioxidants simply by eating plenty of fruits and vegetables. Carrots, citrus fruits, and green leafy vegetables are best.

The bad news is, very few Americans get enough of these vitamins from the food they eat. Don't blame yourself entirely. There's hardly any way for you to eat enough good stuff to take in the amounts of antioxidants that some studies have found to be beneficial.

A shield against free radicals

No doubt, that's why some researchers tell you to take vitamin supplements to build up your body's free radical shield. One problem with that approach is that large doses of antioxidant vitamins may cause your body to relax its own antioxidant defense, some researchers believe.

The best evidence right now says that fruits and vegetables provide all the antioxidants you are likely to need. Although high dose antioxidant supplements may not be dangerous, they are expensive with little data that they actually help.

Just how many fruits and vegetables do you need to protect against free radicals? The U.S. Department of Agriculture's new ChooseMyPlate.gov plan recommends 4- to 5-cup servings of fruit or vegetables a day for an adult. Or try the National Cancer Institute's Five-A-Day campaign, which calls on Americans to eat at least five fruits and vegetables every day.

A lot remains to be learned about the role of free radicals in disease. But it's important to note that the latest research supports established health guidelines, such as those that call for you to stop smoking, exercise moderately -- which may also have an antioxidant effect -- and cut down on fat in your diet.

As new studies better define the role free radicals play in the body, we may find new ways to battle some of the toughest chronic diseases by simply eating better. And there's nothing radical about that.

A three-legged chair

Your body is made up of molecules. Most are stable and resist change. Free radicals, however, are missing a key part, called an electron. Think of a free radical as a three-legged chair. That missing leg makes the chair likely to fall over unless you prop it up.

In the same way, a free radical is unstable and always looking for another molecule to lean on. When that happens, the two molecules combine to create substances that may not be good for your body's health.

Free radicals aren't always hazardous, however. They're essential to many bodily processes. Scientists are trying to determine just what sort of balance of free radicals is best for health.