Skin cancer incidence is on the rise, close to 1 million Americans are diagnosed a year making it the 4^th most costly cancer of the Medicare population. At the same time Vitamin D is emerging in the research as a powerful protector from certain types of cancer and even cavities. The dichotomy is the primary source of Vitamin D is from sun exposure. We are taught to avoid the sun and increase sunscreen use however the incidence of skin cancer continues to rise. So which is it? Should we avoid sun exposure or seek it out to increase our Vitamin D levels. That is one question this study looked at.

This study consisted of 1,108  elderly men, average age of 73, and compared the levels of Vitamin D in their blood and the incidence of developing skin cancer at the start of the study and then again 5 years later. Due to the common perception that exposure to the sun causes skin cancer the researchers expected to see higher levels of Vitamin D in the subjects that had been diagnosed with skin cancer. In order to determine if the Vitamin D levels measured in their blood were due to food supplementation or sun exposure all participants in the study were given questionnaires that covered what foods they ate, activity levels, and how much time they spent outdoors and the blood measurement of Vitamin D was done in such a way that they could differentiate the two.

What they found was that the men in the study that had been diagnosed with skin cancer had lower amounts of Vitamin D than those who had not been diagnosed. They also found a weak correlation of decreased skin cancer in the men who reported the highest levels of walking outside. It is worth noting that the men in this study were from centers in Oregon, Minnesota, and southern California so it was representative of several different geographic areas.

This study supports other research that shows responsible exposure to the sun can increase Vitamin D levels naturally which in turn is protective against certain types of cancers. This should be common sense. We used to spend predominantly all of our time working and playing outdoors. Only recently have we transitioned to a society that spends the majority of our time inside out of the sun. When we do go out we are told the sun is killing us and we need to cover ourselves in sunscreen. As people follow this misleading advice they decrease their sun exposure while skin and many other cancers continue to rise.

So get outside don’t be afraid of the sun. Just engage responsibly by limiting exposure in the beginning of the spring and summer and avoid burning your skin, which is damaging. If needed cover up or use a protective sunscreen like one recommended by www.ewg.org.

Cancer Causes Control 2010 March; 21(3): 387-391

By Dr Scott Szela