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Antioxidants, Free Radicals and Skin Care
Posted: October 15, 2013
By Gerald Imber, MD, the author of The Youth Corridor: Your Guide to Timeless Beauty (KCM Publishing, 2013).
Two scientific terms that have become unavoidable are free radicals and antioxidants. These are now understood to be crucial issues in the health and beauty of one's skin, so pay attention. Free radicals are charged chemical particles of oxygen that enter into destructive chemical bonds with organic substances such as proteins. The result is an oxidation, or chemical burning, of the substance, which destroys it. Protein is denatured, genes may be broken and dangerous residual substances may result from the chemical changes. Examples of oxidation in nonscientific daily life include the rusting of an iron grill left in the atmosphere, the quick browning of cut potatoes, peaches or avocados left in the open air. It is interesting to consider that when a sliced avocado or peach is treated with lemon juice (a source of the antioxidant vitamin C), it does not brown. But before we jump to the conclusion we wish to see, immersing them in water inhibits the oxidation as well. Knowledge of all this has been around for a long time, though only recently has the process become a consuming interest of researchers and health faddists alike. At the same time that the destructive capabilities of free radicals were becoming known, many compounds that combat this destructive oxidation were identified. They are known as antioxidants, and include among their number many vitamins that were felt to be healthful even before the reasons were clarified.
Various activities of daily life have been shown to increase the presence of oxygen free radicals associated with destructive oxidation. Exposure to sunlight is known to lead to oxidative destruction of the skin, including increased incidence of skin cancer and the collagen-destroying processes causing wrinkling. Strenuous aerobic activity has been associated with increased free radical formation. But while athletes produce more free radicals, they may have also developed a more effective method of combating the damage with natural antioxidants. The evidence of free radical production leading to oxidation and tissue damage is real; some of the findings are confusing, and we are only just scratching the surface of understanding a very important mechanism.
Vitamin C has been given credit for all sorts of miracles, proven and unproven. It is a potent antioxidant and a necessary component of tissue collagen production. Again, we are advised that normal diets, including citrus fruit, provide adequate vitamin C. Over the years scientists and clinicians have waffled over claims for the ability of vitamin C to prevent colds and lessen the length of time that symptoms persist. It is generally believed that these qualities are overstated or wrong. One study did show vitamin C to be effective in preventing cold symptoms in 50% of marathon runners tested but only a tiny percentage of the general population. Since I'm so set against subjecting one's body to marathon running, I nearly opted to leave that bit of information out. The significance of all this is confusing.
Antioxidants such as vitamin C are key players in the prevention of cholesterol plaques forming in the arteries and are generally necessary for sustained good health. The importance of vitamin C is well-known for its role in the healing of wounds and maintenance of the integrity of tissues. It is important in collagen synthesis, and its absence causes the disease scurvy, which results in tissue breakdown and open wounds. This was in the past a common condition suffered by sailors during long sea voyages. The association of citrus fruit with prevention of the disease led to British ships carrying stores of limes for consumption on extended passages, hence earning British sailors the nickname "limey."
Excess vitamin C is quickly and harmlessly excreted in the urine. Most proponents believe that 1,000 milligrams per day is adequate for the desired antioxidant effect. A 2008 study quantified the ability of 1,000mg/day of vitamin C to clean up the free radical in muscle after exercise, but questions whether this is beneficial. I'm confused, and I'm sure you are too. Stay tuned—there is surely more to come.
Everything considered, I continue to recommend, and use, daily supplements of 1,000 milligrams of vitamin C.