Sunlight and Health
Sunlight is the double-edged sword. Similar to underdeveloped photography paper, ultraviolet radiation can either be beneficial in fighting disease or harmful if overexposed.
There is an abundance of media attention on the adverse health effects of sunlight. UVA and UVB are the spectrum of sunlight which are hazardous for our health. UVA indirectly destroys DNA by forming free radical and reactive oxygen species. UVB causes sunburns but is also involved in premature aging, skin cancer, and destroys vitamin A within the skin.
In this article, I explore the relationship between vitamin D, circadian rhythm, and diseases.
The hormone Vitamin D is a critical signal molecule. A deficiency is most often caused but lack of sunlight exposure. Overall, Vitamin D as a hormone plays a crucial role in regulating many beneficial genes found in almost all tissues, highlighting its importance for maintaining good health.
Without getting into the nitty gritty of molecular biology. The body produces vitamin D, which is necessary for healthy bones and neuromuscular function, but Vitamin D deficiency has many associations with disease.
Vitamin D deficiency and disease
Multiple sclerosis and Diabetes Type 1 have more prevalence at higher latitudes. Stated differently, the further away from the equator and the less sunlight one receives, the higher the likelihood of developing these diseases. Researchers observed that children who received high doses of Vitamin D had an 80% lower risk of developing Diabetes Type 1, while those with a deficiency had a 4-fold increased risk.
Metabolic disease increases your risk of cardiovascular disease and diabetes type 2. There is an inverse correlation between insulin resistance and elevated blood glucose levels. When vitamin D levels are low, then insulin resistance and blood glucose levels are high. The reason for these remains elusive, but we should note its significance.
Full spectrum ultraviolet radiation emitted from the sun can lower your blood pressure. The experiments showed individuals experienced a significant drop in blood pressure after being exposed to the sun's full spectrum ultraviolet radiation for 3 months.
Vitamin D stimulates the production of cathelicidin, a polypeptide that effectively combats both bacterial and viral infections. The increase in infections, such as flu, RSV, bronchitis, and other viral diseases during winter, is one of the most significant coincidences related to reduced sunlight exposure.
In another study, researchers randomly assigned bipolar depression patients who were admitted to the hospital to receive sunlight exposure with rooms facing morning sunlight. These patients’ hospital stays were shorter than the patients who received evening sunlight.
What is optimal sun exposure?
Individuals are unique. Including skin color and physical differences, sunlight exposure should vary.
2,000 IU/day of vitamin D3 at a cost of less than $20 per year and, unless there are contraindications to sunlight exposure, spending a few minutes outdoors (3–15 minutes for whites and 15–30 minutes for blacks) when the sun is highest in the sky, with 40% of the skin area exposed
Circadian rhythm
Sunlight entering the eye early in the morning is an underrated health benefit.
Melatonin and serotonin are the molecules heavily involved in mood and sleep regulation. Darkness triggers melatonin production, and it plays a crucial role in causing downstream effects that lead to reduced inflammation, cancer, and immune dysfunction.
The body produces melatonin from serotonin. Serotonin, an essential neurotransmitter, influences sleep, mood, and concentration.
Early morning sunlight is one of the ultimate factors in improving sleep and regulating your circadian rhythm. We spend many hours of life indoors. During winter, I often start work before sunrise and finish after sunset. I noticed a significant disturbance in the quality of my sleep.
You will always see from my write-ups, I emphasize sleep as one of the ultimate regulators of health. Sunlight is one of the most important factors needed in sound sleep.
Summary
The balance of sunlight exposure needs to be addressed. Its importance has a significant impact on our health through beneficial biochemical reactions, but we should exercise caution. The role of sunlight can improve mental, mood, immune function, and bone health. When our circadian rhythm is running smoothly, it becomes crucial for regulating several systems. It underpins the importance of early morning sunlight and the associated cascade of positive effects on health. Sunlight is a cheap and underrated treatment for health. The whole idea of sunlight being harmful needs to be curtailed. We need to harness its beneficial effects while balancing the negative effects from overexposure.