By Marc Sorenson, EdD

A very important paper regarding the necessity for sun exposure has recently been published by the journal Medical Hypothesis.[1] It is entitled Regular sun exposure benefits health, and it discusses the pros and cons of sun exposure. One of the salient statements in the paper is that intermittent sun exposure may increase the risk of skin cancer, whereas regular exposure to sunlight might benefit health. For those of us who have for years studied the beneficial effects of sun exposure, the use of the word “might” is the only drawback to the statement. There is no doubt that for the majority of the population, regular sun exposure absolutely protects and enhances health.

Among the diseases mentioned as being reduced or prevented by regular sun exposure are the following:

1. Cancers: Colon, breast, prostate and non-Hodgkin lymphoma
2. Multiple sclerosis
3. Hypertension
4. Diabetes

As the authors mention, most of these positive effects of sun exposure were previously ascribed to Vitamin D, but they point out that immune system function is enhanced by sun exposure beyond the effects of vitamin D, and list other non-vitamin D benefits of the sun, including:

1. Production of nitric oxide
2. Production of melatonin
3. Production of serotonin
4. Regulation of the circadian clock

I have discussed most of these items on the Sunlight Institute web site, but it was good to see new research that, in particular, separated the health benefits of sun exposure from vitamin D production. The idea that has become popularized during the past decade, that all benefits of sun exposure come from increased vitamin D production, is simply not true and can lead to the supplementation of vitamin D as a “cure” for diseases that may not be influenced by that hormone.

Of course, vitamin D is an exceptionally important photoproduct, and the only natural way to attain it is by exposure to the sun or to other sources of UVB light (such as a sunlamp or a tanning bed). The beauty of using these sources, rather than a vitamin-D capsule, is that all of the benefits of nitric oxide, melatonin, serotonin and circadian entrainment are included in the package.

Safely enjoy the sun, and you then will also safely enjoy better health. Remember not to burn, and to gradually develop a good tan.