Americans are increasingly at risk of insufficient sun exposure, according to a landmark study published this week in the Journal of Dermato-Endocrinology.
According to Hoel et al, the message of sun avoidance must be changed to acceptance of non-burning sun exposure sufficient to achieve serum 25(OH)D concentration of 30 ng/mL or higher in the sunny season and the general benefits of UV exposure beyond those of vitamin D. Image credit: Biedermann.
Public health authorities in the United States are currently advising that human sun exposure be reduced.
At the same time, NHANES (National Health and Nutrition Examination Survey) data show that 32% of Americans suffer from vitamin D insufficiency.
“The message of sun avoidance advocated by our government, and some within the medical community, should be changed immediately to a recommendation of regular non-burning sun exposure for most Americans,” said study’s 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.”
Dr. Hoel and co-authors urge U.S. public health officials to change their recommendation regarding UV exposure from ‘sun avoidance’ to ‘moderate UV exposure.’
They cite more than 100 recent studies demonstrating the benefits of non-burning sun exposure.
Many benefits are related to vitamin D, a substance produced naturally in the skin when exposed to UVB in sunlight.
“New data suggest the significant risks associated with sun exposure are only related to sunburn or excessively large lifetime exposure,” the researchers said.
“Vitamin D supplements have not been shown to be an adequate substitute for sun exposure,” they added.
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 deaths linked to tobacco are about 20% (450,000 deaths).
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, according to the authors.
The paper also documents evidence that the health benefits of sun exposure 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.
“Sunlight provides vitamin D, but it provides so much more. The UV from sunlight has other health benefits,” said co-author Dr. Michael Holick, a Professor of Medicine, Physiology and Biophysics at Boston University.
“Most public health agencies have ignored the indisputable evidence that sensible sun is good for you in moderation.”
“Sunscreen should be used as a tool to prevent sunburn, but the public should know that over-use of the product may have unintended consequences,” the authors said.
They are calling for sunscreen labels to contain a statement explaining that sunscreen blocks vitamin D production in the skin.
“Labeling should also acknowledge that sunscreens have not been shown to be effective in reducing the risk of melanoma,” they said.
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David G. Hoel et al. 2016. The risks and benefits of sun exposure 2016. Journal of Dermato-Endocrinology 8 (1): e1248325; doi: 10.1080/19381980.2016.1248325
This article is based on a press-release from GrassrootsHealth, a consortium of scientists, institutions and individuals committed to solving the worldwide vitamin D deficiency epidemic.
