Antioxidants are thought to neutralize and stabilize these free radicals.

So, which antioxidants are naturally found in which foods?

We have:

Vitamin E: a fat-soluble vitamin found in vegetable oils, nuts, green leafy vegetables, and fortified cereals. Some of the foods containing the highest amounts of vitamin E are wheat germ oil, almonds, sunflower seeds, sunflower oil, hazelnuts, peanuts, spinach, broccoli, kiwi and mango.

Vitamin E is an antioxidant vitamin involved in the metabolism of all cells. It protects vitamin A and essential fatty acids from oxidation in the body cells and prevents breakdown of body tissues. 

Vitamin C: Ascorbic acid is a water-soluble vitamin present in citrus fruits and juices, cabbage, green peppers, broccoli, spinach, tomato, kale, guava, cantaloupe, kiwi, papaya, and strawberries.

It is important in forming collagen, a protein that gives structure to bones, cartilage, muscle, and blood vessels. Vitamin C also aids in the absorption of iron, and helps maintain capillaries, bones, and teeth.

Beta-carotene: Beta-carotene is a precursor to vitamin A. It is present in liver, egg yolk, milk, butter, spinach, carrots, squash, broccoli, yams, tomato, cantaloupe, peaches, and grains.

Studies have been done on beta-carotene's effectiveness for heart disease, cancer, chronic fatigue syndrome, Alzheimer's disease, fibromyalgia, male infertility, and psoriasis.

Coenzyme Q10: CoQ10 boosts energy, enhances the immune system, and acts as an antioxidant. A growing body of research suggests that coenzyme Q10 may help prevent or treat some of the following conditions: heart disease, high blood pressure, high cholesterol, diabetes, and others. Primary dietary sources of CoQ10 include oily fish, organ meats such as liver, spinach, broccoli, peanuts, wheat germ and whole grains.

Selenium: Selenium is a trace mineral that is essential to good health but required only in small amounts. It helps synthesize antibodies; helps synthesize co-enzyme Q10and helps transport ions across cell membranes. The best sources of selenium are Brazil nuts, wheat germ, molasses, sunflower seeds, whole wheat bread and dairy foods. 

You should note that there are many other antioxidants naturally found in foods.

You should also note that the best way to take antioxidants is naturally, through fresh, vibrant food. 

One more thing; sometimes less is more. Some of these antioxidants are only needed in small amounts, so check into whether you need to take more or not, before you start overdosing on antioxidants!