The results of a fascinating study were published in the journal Clinical Epigenetics during the year 2015. Scientists at the Cybernetics Research Group in Maine, USA, found among people diagnosed with diabetes, the time of conception and birth was associated with lifespan. Their earlier work had revealed an association between the time of conception and birth to the risk of developing Type 2 diabetes. The risk had been linked to solar cycles which last eleven years. It was concluded exposure to ultraviolet light, the most harmful radiation the sun produces, early in life likely contributes to the development of Type 2 diabetes and its severity.
In March 2015 investigators at Hallym University in the Republic of Korea compared exposure to the sun in individuals enrolled in the 2010 to 2011 Korean National Health and Nutrition Survey V. Their study was reported on in the journal Environmental Research in 2015. It was found the participants with more than five hours of unprotected sunlight per day were more than twice as likely to have Type 2 diabetes than those exposed to fewer than two hours of sunlight without ultraviolet protection. Sun exposure was also associated with belly fat and poorly functioning beta cells, the cells of the pancreas that produce insulin. From these results it was concluded getting less than five unprotected hours of sunlight per day could be helpful in preventing Type 2 diabetes.
The research on ultraviolet radiation and Type 2 diabetes is new and more work will be needed to validate the connection. On the other hand, the role of sunlight in skin cancer is well-known, so protection from too much exposure is wise on that basis alone.
The Centers for Disease Control and Prevention in Atlanta, USA, recommend using a sunscreen with a sun protection factor (SPF) of at least 15, especially during the peak sunlight hours of the day (in the contiguous United States, between 1000 and 1600 hours)…
- hats with wide brims made of fabric such as canvas protect much better than straw hats. The brim should cover the face, ears, and neck.
- clothing should cover both your arms and legs.
- wraparound sunglasses providing ultraviolet A (UVA) and ultraviolet B (UVB) protection are also helpful.
It should be noted indoor tanning machines have the same ultraviolet wavelengths as the sun.
Type 2 diabetics deficient in vitamin D need to spend a few minutes per day in the sun without protection but take care not to overdo it. Mushrooms are also a good source of vitamin D, and specially marked packages indicate which mushrooms have been exposed to ultraviolet light to increase their vitamin D content.