Recently, the Post Dispatch printed an article in the health section that caused a number of people to call our office.
This is a fine example of bench scientists attempting to translate what happens in a lab to a human being. In the experiment, they immerse human lung cells in a solution containing zinc oxide and then expose them to different types of light over numerous time frames. A number of these human lung cells turned cancerous. Zinc oxide is the active ingredient found in many sunscreens. The professor of chemistry found that when zinc particles are exposed to sunlight they release free radicals. We have talked about free radicals multiple times in the past. Free radicals can damage cells and DNA which can increase the risk of cancer. The professor is quick to suggest that “these are very preliminary studies”.
There is no doubt that spending time in the sun increases your risk of skin cancer and early skin aging. The less time you spend in the sun, the less your risk. Sunscreen products have been shown in several studies over the years that when used frequently will lower the risk of squamous and basal cell skin cancers in humans. I need to stress that the present work was done in a laboratory using lung cells and there are no clinical studies to support what this professor is saying about skin cells.
Zinc oxide will help prevent sunburn but what may be as important in your skin therapy is the use of antioxidants. This includes the use of vitamin C, olive leaf extract and green tea which will help absorb the free radicals produced by the sun (and maybe by zinc oxide) which will protect the cells and the DNA from turning into a skin cancer. We have discussed this in previous blogs. To reiterate, it is most important to use combination therapies and this would include zinc oxide sunscreen protection, as well as antioxidants and free radical scavengers in the form of vitamin C, olive leaf extract and/or green tea.
Thomas J. Francel, M.D., F.A.C.S.