Antioxidants are substances or nutrients in our foods which can prevent or slow the oxidative damage to our body. They act as free radical scavengers and prevent and repair damage done by the free radicals. Antioxidants also enhance immune defense and therefore lower the risk of cancer and infection.

Recent medical studies have begun focusing on the health and medical benefits of eating antioxidant-rich fruits and vegetables - specifically the reduction in risk of chronic diseases. The Food and Drug administration (FDA) has gone so far as to release the following dietary guideline for consumers, "Diets rich in fruits and vegetables may reduce the risk of some types of cancer and other diseases."

Antioxidants are phytochemicals, vitamins and other nutrients, and include the following:

Anthocyanins
These are a class of powerful antioxidants that neutralize free radicals that would otherwise damage blood vessel walls, leading to cholesterol and plaque buildup.

Beta carotene
Beta carotene is a proven free-radical scavenger associated with lowered risks for several types of cancer. Research also supports its use in promoting eye health, lowering cholesterol and preventing heart disease.

Magnesium
Magnesium improves the cardiovascular system's antioxidant threshold and increases the body's resistance to free radicals.

Phytosterols
Also called plant sterols, these plant chemicals are valuable in helping to lower cholesterol and high blood pressure.

Polyphenolic Flavonoids
Polyphenols are antioxidant compounds shown to have anti-tumor properties, as well as anti-inflammatory, anti-allergenic and immunostimulatory properties.

Vitamins A, B1, B2, B3, C & E
These vitamins help boost the immune system, improve cellular function, and help reduce inflammation in connective tissues.

Antioxidants neutralize free radicals by donating one of their own electrons, ending the electron “stealing” reaction. In essence the antioxidant terminates the oxidation process by absorbing the free radicals.

Step 1: Antioxidant gives an extra electron to the free radical

Step 2: This atom is now neutralized. The chain reaction of free radicals stops here. This reduces your risk of most sickness and disease.

Antioxidants are present in foods as vitamins, minerals, carotenoids, polyphenols and others. Many antioxidants are identified in food by their distinctive colors - the deep red of cherries or tomatoes; the orange of carrots; the yellow of corn or mango, and the blue-purple of the Açai berry, blueberries and grapes.

While the body has its defenses against oxidative stress, these defenses are thought to become less effective with aging as oxidative stress becomes greater. Research suggests there is involvement of the resulting free radicals in a number of degenerative diseases associated with aging, such as cancer, cardiovascular disease, cognitive impairment, Alzheimer’s disease, immune dysfunction, cataracts, and macular degeneration.

Because oxidation is a naturally occurring process within the body, a balance with antioxidants must exist to maintain health.

Once it was established that antioxidants were beneficial to our health and well-being, the next step was to establish a measure of the substance's (fruit or vegetable) antioxidant properties.

Such a measure was developed by the National Institute of Health and is now recognized by the US Food & Drug Administration. It is called the ORAC Value, which stands for Oxygen Radical Absorbance Capacity. As you would expect, the higher the substance's ORAC value, the better it is at subduing the free radicals and stopping the oxidative process.

The table below shows the ORAC value of a range of common fruits and vegetables:

Dried Fruits & Vegetables ORAC Value (micromoles of TE/g) Açai, freeze-dried 1027 Black raspberry 340 Wild blueberry 260 Wolfberry 220 Red Raspberry 210 Spinach 150 Broccoli 130 Cranberry 125 Red Pepper 90 Tomato 60 Carrot 50