Editor’s Note: Super Home Remedies recommends Advanced Antioxidant with Red Wine Extract and Antioxidant Plus with Grape Seed Extract.

See also: Mangosteen Fruit - Antioxidant Health Benefits from Xanthones ( XanGo )

An antioxidant

is a chemical that prevents the oxidation of other chemicals. In biological systems, the normal processes of oxidation (plus a minor contribution from ionizing radiation) produce highly reactive free radicals. These can readily react with and damage other molecules: in some cases the body uses this to fight infection. In other cases, the damage may be to the body’s own cells. The presence of extremely easily oxidizable compounds in the system can “mop up” free radicals before they damage other essential molecules.

Editor’s Note: “Oxidation” often means the combination or reaction of oxygen with another material. For instance, rust (iron oxide) is formed by the oxidation of iron. A “free radical” is a highly-reactive substance that can be formed when a material is changed by oxidation. This super-charged radical seeks to combine chemically (attack, or react with) other substances in order to regain equilibrium. These attacks by free radicals damage the substance that is attacked, such as living cells. Therefore an antioxidant prevents these radical molecules from attacking healthy cells.

The following vitamins have shown positive antioxidant effects:

• Vitamin A (Retinol or beta-carotene) has been discovered to protect dark green, yellow and orange vegetables and fruits from solar radiation damage, and is thought to play a similar role in human body. Carrots, squash, broccoli, sweet potatoes, tomatoes, kale, collards, cantaloupe, peaches, and apricots are particularly rich sources of beta-carotene.
• Ascorbic acid (Vitamin C) is a water-soluble compound that fulfills this role, among others, in living systems. Important sources include citrus fruits (such as oranges, sweet lime, etc.), green peppers, broccoli, green leafy vegetables, strawberries, raw cabbage, and tomatoes. Linus Pauling was a major advocate.
• Vitamin E, including Tocotrienol and Tocopherol, is fat soluble and protects lipids. Sources include wheat germ, nuts, seeds, whole grains, green leafy vegetables, vegetable oil, and fish-liver oil. Recent studies showed some of tocotrienol isomers has wonderful anti-oxidant properties.
• Selenium is best obtained through foods, as large doses of the supplement form can be toxic. Good food sources include fish, shellfish, red meat, grains, eggs, sunflower seeds, chicken, garlic, and brazil nuts. Vegetables can also be a good source if grown in selenium-rich soils.
• Omega 3 fatty acids prevent formation of atherosclerosis as long as they are taken in conjunction with antioxidants to prevent themselves being oxidized.

It should also be noted that many berries, especially blueberries and blackberries, have particularly high concentrations of antioxidants, as do some types of tea, especially green tea. The FDA has recently suggested that Americans increase their natural antioxidant intake to 7000 ORAC units daily which is nearly 12 servings of fruit to help curb the cancer epidemic.

Several food additives including ascorbic acid (vitamin C) and tocopherol-derived compounds are used as antioxidants to help guard against deterioration of food.

Other antioxidants are enzymes. These include glutathione peroxidase, superoxide dismutase and catalase.

Much damage is done by free radicals in mitochondria as a byproduct of oxidative phosphorylation. Superoxide radicals are generated which can damage mitochodrial DNA and mitochondrial membranes. Unlike DNA in the cell nucleus, mitochondrial DNA has only a few DNA-repair enzymes and the DNA is not protected by histones.

Many antioxidants, however (including vitamin C and vitamin E) can’t get into mitochondria for various reasons (e.g. because too hydrophilic to cross mitochondrial membranes or too hydrophobic to cross the cytoplasm). A group of scientists in Russia (led by V. Skulachev) have created a custom antioxidant (a Skulachev ion forms the point of the molecule and penetrates the mitochondrial membrane; the antioxidising part is attached behind it) that can enter the mitochondria and stays there due to the membrane potential gradient; preventing damage to DNA.

Although there is little doubt that antioxidants are a necessary component for good health, there is considerable doubt as to the most beneficial antioxidant and as to the optimal amount for results. A study of lung cancer patients found that those given antioxidant supplements had worse prognoses. This is believed to be due to antioxidant interference with the body’s normal use of localized free radicals e.g. Nitric oxide for cell signaling. Due to the complex nature of the interactions of antioxidants with the body, it is difficult to interpret the results of many experiments designed to test such things.

For example, recent studies are suggesting that at high levels, synthetic antioxidant vitamins such as A, E and C may prove to have pro-oxidant effects: increasing the formation of free radicals. Regarding the RDA or Recommended Daily Allowance common sense tells us that ten times or 1,000% of your RDA can not be good for you. The fact that natural antioxidants are always ingested together with a wide variety of flavonoids and other phytochemicals also likely plays a part. Many supplement manufacturers supply more expensive tablets containing these.

The benefits of antioxidants were examined during the Age-Related Eye Disease Study.

The Industry

Many nutraceutical and health food companies have, in light of scientific studies, produced products that supplement the diet with such antioxidants. Large companies such as the Nutraceutical Corporation and Natrol have products that are explicitly composed of derivatives that contain antioxidants, like resveratrol in grape seeds. Other companies, such as Canprev Natural Health, produces supplements that contain a combination of antioxidants, like their Immunotality formula.

The green tea industry, with makers like Japanese Green Tea and Arizona (for iced) have benefitted tremendously from recent articles on antioxidants in green tea delaying onset of AMD.

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article “Antioxidants”.

This entry was posted on Thursday, November 10th, 2005 at 5:22 pm and is filed under Home Remedies, Herbal Cures, and Alternative Medicine. Both comments and pings are currently closed.