SPF no match for harmful UV-A

Dear Dr. Gott: Do sunscreens protect against skin cancers?

Dear Reader: Not necessarily, according to an article in Postgraduate Medicine (July 2004).

The author, a professor of dermatology, wrote that 95 percent of the ultraviolet light reaching our skins is made up of UV-A rays, which were heretofore incorrectly assumed to play only a minor role in causing skin cancers. The traditional thinking has been that skin damage and cancers are largely due to UV-B radiation.

Thus, it is understandable that sunscreens were developed to shield against UV-B but not UV-A. Unfortunately, no present commercial products adequately shield the skin from UV-A. The sun protection factor (SPF) refers to a product’s ability to block UV-B rays; this does not mean it has an equivalent ability to block UV-A rays. For instance, a sunscreen with a SPF of 30 may provide an effective UV-A rating of only 2. Consequently, UV-A rays can easily penetrate the chemical barrier and enter the skin, where they generate free radicals, leading to relative immune suppression and an increased risk of melanoma.

Experts now remind us that sunscreens are appropriate for reducing UV-B damage, but to protect against UV-A hazards consumers must use other methods to avoid excessive sun exposure. Such methods include the wearing of comfortable clothing, a hat and UV-reducing sunglasses.

To give you related information, I am sending you a copy of my Health Report “What You Should Know about Skin Cancer.” Other readers who would like a copy should send a long, self-addressed, stamped envelope and $2 to Newsletter, P.O. Box 167, Wickliffe, OH 44092. Be sure to mention the title.

Dear Dr. Gott: I read your article about cranberry juice reacting badly with Coumadin. Also, I know that grapefruit may as well. How about other fruits and juices, such as oranges, grapes, apples and bananas? My wife has a hard time keeping her INR blood test (which monitors her anticoagulation medication) in the proper therapeutic range.

Dear Reader: Cranberry, grapefruit and broccoli can interfere with Coumadin therapy. The fruits you mentioned will not. I suggest that your wife question and work with her physician to discover what foods and beverages appear to be affecting her blood coagulation.

Dear Dr. Gott: I have had two operations to correct a dropped bladder. Now my gynecologist wants me to use an estrogen ring, but I hesitate because of all the bad press about the serious consequences of hormone therapy. My physician, my gynecologist and my pharmacist unanimously agree that the risks of Estring are negligible because the hormone affects only the area where it is needed. What is your opinion?

Dear Reader: To my knowledge, Estring is a safe and reliable option that is free from the negative effects of estrogen pills or patches.