We’ve known for quite some time now, based on observational evidence, that exposure to sunlight is helpful for those who are sick with a variety of illnesses, particularly viral illnesses. Well, just this week a paper was published regarding an experiment done using near-infrared light to treat those who were hospitalized with COVID-19. The result was that those who were treated with near-infrared light did much better, with an average of 4 days less time in the hospital, compared to those who were not exposed to near-infrared light (Link).
Dr. Roger Seheult, a quadruple-boarded internal medicine doctor and an expert in COVID-19, goes into detail regarding this study and just why it is that exposure to sunlight is so helpful when it comes to viral and other illnesses (Link).
Based on the current evidence in hand, it seems as though sunlight, particularly the near-infrared portion of the spectrum, is able to penetrate the body with its warming rays (through clothing as well) up to 8 cm deep. And, the cells of the human body respond to this near-infrared light by producing the hormone melatonin. Melatonin is commonly known to be released at night by the pineal gland during sleep, and is thought to regulate the sleep/wake cycle. What is less commonly known is that melatonin is also a powerful antioxidant that reduces oxidative damage throughout the body. The vast majority of melatonin is produced, not by the pineal gland during sleep, but during exposure to near-infrared light during the day. Also, exposure to infrared light significantly reduces cell damage caused by ultraviolet B (UVB) light/radiation (Link), which reduces skin aging (Link).
This is right in line with the long-recommended Seventh-day Adventist health advice based on the writings of Ellen White:
“The feeble one should press out into the sunshine as earnestly and naturally as do the shaded plants and vines. The pale and sickly grain blade that has struggled up out of the cold of early spring, puts out the natural and healthy deep green after enjoying for a few days the health-and-life-giving rays of the sun. Go out into the light and warmth of the glorious sun, you pale and sickly ones, and share with vegetation its life-giving, health-dealing power.” Ellen White, The Health Reformer, May 1, 1871.