Antioxidant molecules in our bodies inhibit the oxidation of other molecules and neutralize “free radicals,” or unstable compounds. Free radicals are created by oxidation, a chemical reaction involving the loss of electrons in a molecule. More familiar examples of oxidation are butter going rancid, iron rusting, apple slices browning and fires burning. Apply antioxidant-rich lemon juice to your sliced apple, and what happens? The flesh will resist browning.
Free radicals accelerate aging and contribute to many chronic illnesses, including Alzheimer’s disease, arthritis, atherosclerosis, cancer, cardiovascular disease, cataracts and diabetes. To stabilize themselves, free radicals snatch electrons from other atoms or molecules, which can then spark a chain reaction of electron raiding.
While the body’s free-radical production is normal and sometimes even useful, an overload of oxidation can damage molecules, such as DNA, fats and proteins, thereby disrupting cell functions. In addition, oxidation stirs up inflammation, which generates more free radicals.
Other conditions heighten free-radical formation and oxidative stress: tobacco smoke, certain forms of pollution, fever, infection, chronic inflammation, chronically elevated blood glucose (diabetes), ultraviolet light and radiation, extreme exercise, and consumption of unhealthy hydrogenated fats, such as trans fats and oils in fried foods.
Many normal bodily processes create free radicals, such as when our bodies break down nutrients for energy, fight off infection or detoxify drugs. But the body also produces its own antioxidants to neutralize free radicals — a process that works well until an excess of free radicals overwhelms the system.
Eating antioxidant-rich foods can restore the balance. Animal products contain some antioxidants, but your richest sources are plants, which contain antioxidants such as vitamin C, vitamin E, selenium, carotenoids and flavonoids.
Carotenoids and flavonoids double as plant pigments, so eat a variety of colorful fruits and vegetables, as well as culinary herbs and spices, to maximize your dietary antioxidants. Particularly rich sources include berries, cherries, red grapes, papaya, pumpkin, carrots, green tea, garlic and cruciferous vegetables, such as broccoli, cabbage and kale.
Now that you know how antioxidants work in your body, learn more about building a diet around them by reading The Best Antioxidant-Rich Foods for a Disease-Fighting Diet.
Photo by Dreamstime/Maffboy: Eat your colors! Vividly hued foods, such as these bright berries, are rich in antioxidants.