Let the Sun In, Again
This week, I’ve been reporting on an important, controversial message from an influential segment of the medical community. When it comes to sun exposure, conventional medical wisdom warns: “Avoid unprotected exposure to strong sunlight” at all times. But now an impressive group of international experts offers a distinctly dissenting opinion. In a nutshell, they argue that, for optimal health, we all need to strike a healthy balance between sun avoidance and sensible sun exposure.
To be sure, that’s not a message you’re likely to hear from a dermatologist. Skin disease specialists—some of whom must treat skin cancers, including deadly melanoma—remain firm in their commitment to urging all of us to avoid sun exposure during prime burning time. They also urge everyone to wear sunscreen—and reapply often—whenever venturing out of doors.
But according to a broad coalition of experts in endocrinology, vitamin D, and other areas of medicine and nutrition, a little moderate ultraviolet exposure is a good way to improve human health naturally. Writing in a recent issue of the Journal of the American College of Nutrition, they noted that vitamin D production is driven by the action of UV light striking bare skin. Higher levels of natural vitamin D are linked to lower rates of cancer, among other illnesses, and may even play a role in susceptibility to autoimmune diseases, such as multiple sclerosis (MS).
For example, MS is more prevalent at higher latitudes, meaning in places where the sun is weaker, and people’s vitamin D levels tend to be lower. In addition, say the authors of the dissenting new paper, sunlight exposure also stimulates the release of important, beneficial compounds such as nitric oxide (which relaxes blood vessels, lowering blood pressure), and beta-endorphins, which function to promote feelings of wellness. Sun exposure is also important for regulating the daily 24-hour cycle known as the circadian rhythm.
"We urge the US Surgeon General's office and other public health entities to do the work needed to recommend UV exposure levels that are both beneficial and safe, and which favor scientifically-researched information over current cultural norms,” said study co-author, Carole Baggerly, executive director of GrassrootsHealth.
I’m not urging anyone to go out midday, completely unprotected, and court a sunburn. Everyone agrees that sunburn is harmful. But I’m presenting this new perspective so you can make informed decisions for yourself. Moderation is almost always best, and this new outlook suggests that we may be taking sun avoidance a little too far for our own good, at least in some cases. In any event, it can’t hurt to shine a little light on this emerging controversy.
Carole A. Baggerly, Raphael E. Cuomo, Christine B. French, Cedric F. Garland, Edward D. Gorham, William B. Grant, Robert P. Heaney, Michael F. Holick, Bruce W. Hollis, Sharon L. McDonnell, Mary Pittaway, Paul Seaton, Carol L. Wagner, Alexander Wunsch. Sunlight and Vitamin D: Necessary for Public Health. Journal of the American College of Nutrition, 2015; 34 (4): 359 DOI: 10.1080/07315724.2015.1039866