Q. I was at the beach last week and didn’t venture out without my high-powered sunscreen (SPF 45). It worked so well that I never burned. In fact, I never even got pink. I am as pale now as before the trip.
That got me to wondering whether sunscreen has any effect on vitamin D formation. I wear sunscreen daily as my dermatologist has recommended. Do I need supplements?
A. You should ask your doctor to run a blood test to check your level of 25-hydroxyvitamin D. This is an indicator of your vitamin D status and is the best way to tell if you may need a supplement.
Your observation from the beach is on target. Sunscreen that effectively prevents sunburn also blocks most production of vitamin D in the skin (Dermatoendocrinology, Jan/Feb/March, 2013). If you must avoid sun exposure for medical reasons, you may need a supplement. If you are simply being prudent about avoiding sunburn, you might consider brief (15 to 20 minute) exposures without sunscreen a few times a week. In many cases, that will produce adequate vitamin D without risking your skin.
You can learn more about the importance of vitamin D and appropriate doses for supplementation from the Guide to Vitamin D Deficiency we are sending you. You may also be interested in our guidelines for protecting yourself from sunburn in our Guide to Skin Care and Treatment.
There are a few foods (tomatoes, chocolate) you might want to include in your summertime diet to diminish your risk of sunburn. They won’t replace sunscreen, but they may help you feel safer with those brief exposures.
