Most of the harmful reactions caused by smoking are the result of free radicals. Free radicals are unstable molecules that have missing electrons. They pillage your body's healthy molecules for replacement electrons, leaving more free radicals and damaged cells and tissues in their wake. This process is called oxidation, and it's what makes iron rust and fruit turn brown. And some scientists are beginning to believe that oxidation is what makes people age.

Though free radicals are formed during everyday functions such as breathing, environmental stress factors such as smoking dramatically accelerate their production. In fact, each cigarette generates millions of free radicals, making smokers much more susceptible than nonsmokers to the ravages of oxidative tissue damage.

To fight this free radical onslaught, you need a strong defense. And, according to research, one of the best defenses consists of nutrients known as antioxidants, such as Vitamin C, the B group of vitamins, and beta-carotene. Antioxidants act to circumvent free radicals, protecting your body's healthy molecules by sacrificing their own electrons to neutralize hostile free radical invaders.

Though antioxidants aren't miracle cures and certainly shouldn't lure you into a false sense of security about smoking, these nutrients can help to stave off smoking-related damage whether you are staying with the habit or kicking it.