More and more studies show that people don’t have enough vitamin D, which is produced when sunlight hits our skin. Does this mean we should stop using sunscreen? Should we decrease the SPF (sun protection factor)? Or should we continue using sunscreen and take vitamin D supplements?
The truth about vitamin D and sunscreen is complicated. I don’t believe the heated rhetoric of this debate, and I believe that moderation is the best approach. Humans have evolved to live outside and get sun. The problem is that our skin has evolved in several parallel pathways so that it can get more or less sun depending on the latitude it has adapted to live in. Darker skin has evolved for more sun exposure, while lighter skin has evolved for more northern latitudes. If a light-skinned person is put in a sunny environment, their skin won't have the protection it needs and will tend to get burned. Over the long term this exposure will manifest as skin cancers, precancers, and premature aging including wrinkles.
Very few light-skinned Americans are getting enough vitamin D. This can and should be measured on an annual basis, especially for those that live in a climate that does not expose them to much sun light. If you have a low vitamin D level, you can plan a strategy that supplements it with oral vitamin D, and this can be done with your physician. There are a few different forms of vitamin D, and the one that you should monitor is called 25 (OH) D. According to the National Institute of Health, a level of about 20 ng/ mL is appropriate for most people. Having a level higher than this can predispose to formation of kidney stones because vitamin D will increase calcium absorption. Less than this level can affect bones and other vital structures.