Insufficient Sun Exposure Called Emerging Public Health Problem By World-Renowned Researchers
Public health advice to avoid sun exposure may be contributing to more than 300,000 deaths annually; Researchers from Medical University of South Carolina, Boston University, University of New Mexico and Leiden University (Netherlands) call for U.S. public health officials to encourage moderate non-burning UV exposure
A landmark study published today in the Journal Dermato-Endocrinology has world-renowned researchers calling insufficient sun exposure an emerging health problem in the United States. In their paper, The Risks and Benefits of Sun Exposure 2016, the authors reference more than 100 studies, including several major papers in the past five years, in concluding that Americans are not getting enough sun exposure and that public health advice needs to be retooled to embrace moderate sun while focusing on sunburn prevention.
“The message of sun avoidance advocated by our government, and some within the medical community, should be changed immediately to a recommendation of moderate non-burning sun exposure for most Americans,” said lead author Dr. David Hoel, a member of the National Academy of Medicine and Distinguished University Professor at the Medical University of South Carolina. “The sun is essential for life and should be diligently pursued in moderation, not avoided.”
While recent public health guidance has encouraged people to avoid the sun out of concern that exposure will increase risk of skin cancer, the prevalence of vitamin D insufficiency in the United States is 70%. The study cites recent estimates that about 13% of all U.S. deaths (330,000 deaths per year) could be attributable to vitamin D insufficiency. Corresponding estimates for smoking are about 20% (450,000 deaths).
“The body of science concerning the benefits of moderate sun exposure is growing rapidly,” Hoel stated. “Increasing time in the sun is critical for achieving the recommended vitamin D serum blood levels of 30 ng/mL or higher in the sunny season, as well as acquiring the benefits of UV exposure beyond those of vitamin D.” The paper notes that the health benefits of sun avoidance are not limited to vitamin D, with nitric oxide and other sun-induced mediators identified with respect to reduced hypertension and other favorable health outcomes. Vitamin D supplements have not been shown to be an adequate substitute for sun exposure. Risks of insufficient sun exposure include increased risk of many types of cancer, cardiovascular disease, Alzheimer's disease/dementia, diabetes, multiple sclerosis, myopia and macular degeneration.
The paper’s conclusions and call for a change in public policy are significant given the strong and diverse qualifications of its multi-disciplinary authors:
- Dr. David Hoel, recognized as one of the world’s leading experts on the health effects of radiation, served on the World Health Organization’s International Agency for Research on Cancer (IARC) panel of experts which in 2009 classified ultraviolet radiation (UVR) as a carcinogen. Dr. Hoel has since called this classification widely misunderstood, noting that UVR is associated with skin cancer only if it results in sunburn or if it is in very large lifetime amounts.
- Dr. Marianne Berwick is the distinguished professor of dermatology and internal medicine at the University of New Mexico, is widely regarded as one of the world’s leading experts on melanoma epidemiology.
- Dr. Frank de Gruijl, associate professor of dermatology at Leiden University in the Netherlands, considered one of the world’s leading pigment cell/melanogenesis researchers.
- Dr. Michael Holick is professor of medicine, physiology and biophysics at Boston University and perhaps the world’s most recognized vitamin D researcher. Dr. Holick was on the research team that first discovered the active form of vitamin D in 1969.
The paper notes that sunburns have been associated with a doubling of the risk of melanoma and non-melanoma skin cancers, and should therefore be avoided. While sunscreen can be an effective tool in preventing sunburn, the authors encourage public health authorities to require product labeling informing consumers that vitamin D deficiency may result from excessive use, and that sunscreens have not been shown to be effective in reducing the risk of melanoma.