UVB exposure benefits by Marc Sorenson, EdD. Sunlight Institute…
UVB is a spectrum of sunlight that is responsible for stimulation of vitamin D production in the skin. It also has many other effects, including the suppression of inflammation in the skin, and thus has been used to very successfully treat skin diseases such as psoriasis and eczema.   
Since inflammation is also necessary to produce the condition of atherosclerosis (arterial plugging or occlusion) in arteries, it would be interesting to know whether UVB light might also have the same anti-inflammatory effects in those arteries. If so, the UVB effect could inhibit or eliminate atherosclerosis, and by so doing provide an entirely new treatment for heart disease and other vascular events such as stroke and intermittent claudication.
The idea that UVB could prevent atherosclerosis by reducing inflammation in arteries was recently studied by Japanese researchers.  Using a mouse model, they demonstrated that UVB light irradiation, once weekly for 14 weeks, leads to an increase in the action of T-regulatory cells that inhibit inflammation. In addition, UVB exposure also reduced the production of another type of T-cell that is pro-inflammatory, and thereby proatherogenic (leading to the production of atherosclerosis). These two effects of UVB light reduce the development and progression of atherosclerosis. Or stated differently, the research shows that sun exposure is critically-important therapy to reduce and prevent heart and other vascular diseases.
Protect your heart by being sure to obtain sufficient non-burning UVB light from sun exposure or other sources such as the UVB lamps used by the researchers. It is important to note that neither skin cancer nor skin inflammation were observed following UVB exposure.
This is another breakthrough study that emphasizes the necessity of sun exposure for human health.
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 Naoto Sasaki, Tomoya Yamashita, Kazuyuki Kasahara, Atsushi Fukunaga, Tomoyuki Yamaguchi, et al. UVB Exposure Prevents Atherosclerosis by Regulating Immunoinflammatory Responses. Arterioscler Thromb Vasc Biol. 2016;36:00-00.
 Hafid Ait-Oufella, Andrew P. Sage. Editorial. The Sunlight. A New Immunomodulatory Approach of Atherosclerosis. (Arterioscler Thromb Vasc Biol. 2017;37:7-9. DOI: 10.1161/ATVBAHA.116.308637.)