By Dr. Richard Thomas
If you want to protect your skin, think antioxidants.
These have gained a great deal of attention in recent years, and for good reason.
They work to combat the ‘free radical cells’ that damage your skin.
Created when oxygen produces by-products during normal cellular metabolism. More accurately, this reactive oxygen ‘steals’ electrons from proteins, DNA and cell membranes, damaging tissue. If left unchecked, free radicals may cause heart damage, cancer, cataracts, and a weak immune system. Free radicals may be involved with aging of tissue; and coupled with sun damage, could promote skin cancers. While free radicals are produced by normal human metabolism, they can be increased by smoking, alcohol, exposure to heavy metals, and radiation. Antioxidants counteract this process by binding to the free radicals, transforming them into non-damaging compounds, or repairing cellular damage. It would seem logical, then, to include antioxidants in your daily regime.
To the rescue: Antioxidants are the antidote to free radicals. They can be taken orally or applied directly to the skin.
What are antioxidants?
In order for antioxidants to have any benefit they have to be in sufficient quantities in the tissue. Common antioxidants that are taken orally, or eaten, are Vitamin C, Vitamin E, Selenium and the carotenoids, (fruits and vegetables having the most deeply or brightly-colored fruits and vegetables, i.e.: spinach, carrots, red bell peppers, tomatoes).
What are topical antioxidants?
Topical antioxidants may reduce UVA damage. UVA is the wavelength that mostly produces visible signs of sun damage and has some carcinogenic effect.
Topical antioxidants that have been studied in creams or ointments are Vitamin C, Vitamin E, Glutathione, Lipoic Acid, Coenzyme Q10, Soy- isoflavanone. It has been shown that combining some of these have additional benefit.
Others such as selenium, zinc and silymarin have not been studied for their effects.
Which are the antioxidants?
Antioxidants can be divided into those that are fat soluble and those that are water soluble.
Fat soluble is:
- Vitamin E, coenzyme Q10 and lipoic acid
Water soluble is:
- Glutathione and Vitamin C
- The antioxidant effect can be more effective if combined with other antioxidants i.e.: coenzyme Q10 and Vitamin C
- Is found in fresh vegetables, oils, seeds, nuts, cumin, and soy. Animal studies have shown that Vitamin E protects against UVB damage, although this effect has not been proved in humans. (UVB is much more carcinogenic than UVA, and causes sunburns).
- Commonly used to help wound healing. However, studies in human burns did not show Vitamin E helping and about a 1/5 of patients reacted to vitamin E with a contact dermatitis).
- Topical Vitamin E is commonly used by pregnant women in the belief that it prevents stretch marks. There is no evidence for this, and sometimes an acute allergic dermatitis is produced causing an inflamed uncomfortable rash.
Coenzyme Q10 (also known as Ubiquinone)
- Found in fish and shell fish
- It penetrates well into skin, and is claimed to reduce the breakdown of collagen after exposure to UVA light
- It may reduce the depth of wrinkles but this has not been confirmed in studies
- This is well absorbed into the skin, and converted quickly into dihydrolipoic acid in the cells. It has an anti-inflammatory effect. A three per cent application of Lipoid Acid has been shown to reduce redness in the skin after UVB exposure.
- This antioxidant is produced by amino acids, eysteine, glycine and glutamic acid
Also known as Ascorbic Acid
Oral Vitamin C improves wound healing and may enhance the immune system
The lack of vitamin C produces scurvy, which produces fragile skin and bleeding gums
Topical Vitamin C
- reduces sun damage, fine wrinkles, and may lighten dark skin pigmentation
- The lack of vitamin C produces scurvy, which produces fragile skin and bleeding gums
Green Tea (Tea Polyphenols)
- Has shown to reduce the carcinogenic effect of certain chemicals and ultraviolet rays on the skin of animals. We are still awaiting good evidence for benefit in humans
- Produces anti-inflammatory effects
- Reduces the redness caused by UV light
- Occurs naturally in our bodies
- When taken orally, DHEA is a powerful antioxidant that may have an anti-aging effect and help thicken skin and reduce pigmentation
- It is not know if there are any long-term negative effects from oral injection
- When used topically it may increase collagen and decrease redness and damage from ultraviolet rays
About the author:
Richard Thomas, MD, FRCPC is Assistant Professor of Clinical Dermatology, Department of Dermatology, University of British Columbia, Vancouver, Canada.