Antioxidants are substances or nutrients in our foods which can prevent or slow the oxidative damage to our body. When our body cells use oxygen, they naturally produce free radicals (by-products) which can cause damage. Antioxidants act as "free radical scavengers" and hence prevent and repair damage done by these free radicals.



Antioxidants are found in the nutrient antioxidants, vitamins A, C and E, and the minerals copper, zinc and selenium. Other dietary food compounds, such as the phytochemicals in plants and zoochemicals from animal products, are believed to have greater antioxidant effects than either vitamins or minerals. These are called the non-nutrient antioxidants and include phytochemicals, such as lycopenes in tomatoes, and anthocyanins found in cranberries.

An antioxidant is a molecule capable of slowing or preventing the oxidation of other molecules. Oxidation is a chemical reaction that transfers electrons from a substance to an oxidizing agent. Oxidation reactions can produce free radicals, which start chain reactions that damage cells. Antioxidants terminate these chain reactions by removing free radical intermediates, and inhibit other oxidation reactions by being oxidized themselves.

It's little surprise that antioxidants have acquired a reputation as miracle health supplements. As long ago as the 1950s, scientists discovered that many diseases - including heart disease, strokes, cancer, diabetes, cataracts, arthritis and neurodegenerative disorders such as Parkinson's and Alzheimer's - were linked to damage caused by highly destructive chemicals called free radicals.

The largest and most advanced analysis of the antioxidant content of common foods to date shows that disease-fighting antioxidants may be found in unexpected fruits and vegetables, such as beans, artichokes, and even the much-maligned Russet potato.

Antioxidants work by significantly slowing or preventing the oxidative - or damage from oxygen - process caused by substances called free radicals that can lead to cell dysfunction and the onset of problems like heart disease and diabetes. Antioxidants may also improve immune function and perhaps lower your risk for infection and cancer.

Using dietary supplements of antioxidants to prevent cardiovascular disease should not be recommended until their effect is proved in clinical trials that directly test their impact on CVD end points. Beneficial effects must be demonstrated in well designed (randomized, placebo-controlled) clinical trials before recommending widespread use to prevent cardiovascular disease.

Antioxidants can be conceptualized in a number of different ways: as insurance against some of the more visible effects of aging; as a weapon in our fight to make our average life expectancy more closely resemble our ultimate lifespan; and as a line of defense against the risk of developing certain illnesses and diseases.

Antioxidants are compounds that protect cells against the damaging effects of reactive oxygen species, such as singlet oxygen, superoxide, peroxyl radicals, hydroxyl radicals and peroxynitrite. An imbalance between antioxidants and reactive oxygen species results in oxidative stress, leading to cellular damage. Oxidative stress has been linked to cancer, aging, atherosclerosis, ischemic injury, inflammation and neurodegenerative diseases (Parkinson's and Alzheimer's).

Vitamin C helps some of our most important body systems. First and foremost, it helps the immune system to fight off foreign invaders and tumor cells. Vitamin C also supports the cardiovascular system by facilitating fat metabolism and protecting tissues from free radical damage, and it assists the nervous system by converting certain amino acids into neurotransmitters.

Researchers say the antioxidant found in grape skins, known as resveratrol, appears to work by targeting the cancer cell's energy source from within and crippling it. When combined with radiation, treatment with resveratrol prior to radiation also induced cell death, an important goal of cancer treatment.