Here is the UK the weather has brightened a bit of late and, rather predictably, news stories are already starting to warn us that sunlight can boost skin cancer (specifically, malignant melanoma) risk [click here]. However, I do believe that when it comes to examining the relationship between a lifestyle factor and disease, we should be wary about focusing on just one condition.
Sunlight exposure increases vitamin D production in the skin, and earlier this week I reported on some research linking this nutrient with a reduced risk of raised blood pressure. But perhaps even more importantly, there is a stack of evidence suggesting that vitamin D has cancer-protective properties too.
Not surprisingly, then, there is also a considerable body of evidence that links increased sunlight exposure to a reduced risk of several cancers including some of the ‘biggies’ such as cancer of the breast, prostate and colon. Put another way, reduced sunlight exposure might actually increase the risk of several common cancers.
Now, while malignant melanoma is a condition that is certainly worth avoiding, it remains a relatively rare cancer. So, it is entirely possible that by shying away from sunlight, we might actually be increasing our overall risk of cancer. Also, sunlight exposure is associated with a reduced risk of multiple sclerosis too.
I have written about the broad benefits of sunlight, including its seeming cancer-protective properties in the past. In the last few months have been made aware of the website www.sunarc.org which I think does a very good job of presenting evidence for the health benefits of sunlight and the vitamin D derived from it. Click on the link entitled The role of ultraviolet-B (UVB) radiation (290-315 nm) and Vitamin D in reducing the risk of cancer for a detailed appraisal of this area.
While sunlight appears broadly beneficial, I recommend protecting against sunburn. Protecting the body with appropriate clothing and seeking the shade when the sun is at its most intense are obvious precautions to take. However, that caveat aside, I think its important to bear in mind that the current scare stories about skin cancer need to be tempered with a wider view of the effects of sunlight on cancer risk and general health.