We tend to regard sunlight as an essential ingredient for making our plants and crops grow and produce enough food and fiber for us to harvest but forget how truly necessary it is for human development.
We, too, are built to absorb the sun’s rays through our skin, triggering numerous positive processes within our bodies and promotion of overall longevity:
Builds and fortifies bones and teeth
Probably the most well-known benefit of exposing skin to sunlight is creation of the chemicals we need to produce vitamin D, and the best-known effect of vitamin D is its contribution to bone growth by letting the body absorb calcium and phosphorous. Higher levels of vitamin D3 in our bloodstream directly reduce our risk of bone fractures and osteoporosis.
Reduces blood pressure
Scientists report the sun’s rays also result in immediate releases of nitrogen oxides from our bodies’ stores of these chemicals, which in turn dilates our blood vessels, lowering blood pressure and aiding the circulatory system in ways that could reduce heart disease risk.
Improves mood and reduces pain
The sun’s rays trigger production of beta-endorphins, which have been linked to pain suppression and the “runner’s high” experienced after this and other forms of exercise. Sunlight also leads to increased serotonin production, improving our feelings of well-being and self-esteem, keeping us alert and regulating our sleep cycle, which we’ll talk more about below.
Aside from encouraging production of serotonin, sunlight is a powerful environmental cue regulating our circadian rhythms by launching our waking cycle through the production of cortisol, known as the “stress hormone,” but in lower does it activates us to wake up and starts the day. Waning sunlight, on the other hand, triggers production of melatonin to slow our brains down and prepare us for sleep. People having trouble sleeping are often advised to expose themselves to sunlight early in the day to help “reset” their sleep cycle.
Lowers risk of some diseases
According to a 2016 review of scientific studies, higher exposure to sunlight has been associated with reduced incidence of multiple sclerosis, non-Hodgkin’s lymphoma, diabetes and colon, breast and prostate cancer.
We’re also aware of the sun’s role in causing skin aging and skin cancer. This has produced a tug-of-war within the scientific community and our own minds on how much sun we should be getting, especially since wearing sunscreen blunts any positive effects of ultraviolet rays, along with the negative.
How much unscreened sunlight we should be absorbing depends on many factors such as the time of year, time of day, skin color, age, amount of skin exposed and body weight. Skin cancer risk rises with every sunburn, so many experts advise going inside or applying sunscreen after 15 to 20 minutes of midday exposure during the summer, a number that can go up to 90 minutes to 2 hours in the winter.