Benefits of sun exposure, by Marc Sorenson, EdD…
Interesting research regarding the critical necessity of sun exposure continues to mount.
There is no doubt that lack of sun exposure leads to disease, and a major factor in that scenario is a disrupted circadian rhythm. Researchers have stated that “Exposure to sunlight during the day, and darkness at night, optimally entrains biological rhythms to promote homeostasis and human health. Unfortunately, a major consequence of the modern lifestyle is increased exposure to sun-free environments during the day and artificial lighting at night.”[1] Night-shift work is one of the worst contributors to the disruption of our natural biological rhythms, also known as circadian rhythms, and it certainly defines the sun-free environment discussed. There is a strong association of night-shift work to many diseases, but one of the most prevalent of these is breast cancer.
So what is natural and good for the health? Researchers have shown that a disrupted circadian rhythm can be reprogrammed, or “entrained” by exposure to a natural summer, meaning a cycle of 14 hours, 40 minutes of summer light, to 9 hours, 20 minutes of darkness.[2] The authors state that this “light-dark cycle programs the human circadian clock to solar time, such that the internal biological night begins near sunset and ends near sunrise.”
Such a cycle would certainly seems natural for humans who were raised on ranches or farms where the day’s activities begins early in the morning sunlight and usually end near sunset. I know, because that pattern described my youth. For primitive peoples, that cycle was probably a necessity to gather the food necessary for survival. It is now ingrained in to our DNA, and disruption leads to disease.
So how are circadian rhythms reset to help our health? According to the aforementioned research (footnote 2), it can be accomplished by either a week of natural light exposure, or a weekend spent camping in nature. I am a camper, and I know that when the sun goes down, I am ready to sleep, and when the sun rises the next morning, I’m ready to start my day’s adventures.
The message here is that daytime should be spent outside in natural light. This will probably reduce the risk of many diseases, including breast cancer. It is also imperative that our skin receives its sun exposure to produce vitamin D and other healthful photoproducts. In addition being outside in the sun will increase our production of serotonin and enhance our moods.
Safely embrace the sun and save your life! Be sure not to burn.
[1] Ball L, Palesh, O, Kriegsfeld L. The Pathophysiologic Role of Disrupted Circadian and Neuroendocrine Rhythms in Breast Carcinogenesis. Endocr Rev. 2016 Oct;37(5):450-466.
[2] Stothard ER, McHill AW, Depner CM, Birks BR, Moehlman TM, Ritchie HK, Guzzetti JR, et al.