It’s summertime: the perfect time of year to get outside and soak up some rays. But getting exposed to the sun isn’t just about getting bronzed or cervezas by the pool. Planet Earth has been bathing in sunlight for more than 3 billion years. Given the importance of sunlight for life on this planet, it only makes sense that all lifeforms, including humans, have evolved to use the power of the sun to their advantage. Honestly, you may be surprised by the benefits of sunlight when it comes to your health.
Vitamin D production
Let’s address the most well known benefit of the sun for our health first: Vitamin D synthesis. At least 1,000 different genes governing virtually every tissue in the body are now thought to at least have some regulation by Vitamin D. This includes everything from immune system functioning to bone formation. Unlike most other essential vitamins which must be obtained from food or supplementation, the best way to obtain Vitamin D is through sunlight. An added bonus is that you cannot overdose on Vitamin D when you obtain it from the sun.
Exposure to sunlight helps to synchronize or even reset your circadian rhythms. This can be extremely helpful to those suffering from difficulty falling asleep at night or for travelers returning from a different time zone. When people are exposed to sunlight, their nocturnal melatonin production occurs sooner, allowing them to enter into sleep more easily at night. The melatonin rhythm phase advancement caused by exposure to bright morning light has been effective not only for insomnia but also for premenstrual syndrome and seasonal affective disorder.
Happy days from sunshine rays. You just read that sun exposure can be therapeutic for seasonal affective disorder, but what the hell is that? Seasonal affective disorder, sometimes known as the “winter blues”, is a constellation of symptoms of depression, fatigue, and/or lack of motivation that typically occurs in the fall and winter when our sunlight exposure is at its lowest. There is a link between this condition and lack of light exposure. Bright light therapy is one of the primary ways to treat this condition. Sunlight exposure can actually benefit many types of depression as well though! Serotonin and dopamine are the two chemicals in the brain that are largely responsible for positive outlook, attention, calm-attitude, motivation, wakefulness, and even learning. It is no coincidence that both of these chemicals are highly affected by exposure to daylight with increased amounts being produced by the body with increased daylight exposure.
Lowers Risk of Disease
Finally, sunlight exposure has been shown to decrease your risk of developing (or at least improving) symptoms in numerous diseases, both acute and chronic. On the acute side, sunlight and Vitamin D helps the body to produce cathelicidin, a molecule in the body that effectively combats both bacterial and viral infections. This may be one mechanism that explains why viral infections like influenza are so much more common in the late fall and winter. There also appears to be a substantial link between sunlight exposure and the risk/severity of several diseases. The following diseases have been shown to have increased risk and/or mortality as populations gets further north/south from the equator: Heart disease, High blood pressure, Multiple sclerosis, Parkinson’s disease, Type I diabetes, Type II diabetes, Thyroid disease, Lupus, Inflammatory bowel disease, and several forms of cancer including Hodgkins lymphoma, as well as breast, ovarian, colon, pancreatic, and prostate cancers. This is just the beginning as well! Scientists are learning more every year on the link between lack of sunlight exposure and disease.
Phew, we just took a dive into the science of the health benefits of sunlight. If you skipped a few parts and just want the CliffsNotes version, here you go... More sunlight equals better all around health.
We live in a culture where we are afraid of the sun, but the sun is something that we are fundamentally connected with and we will continue to be dependent upon . We don’t have to always slather on the sunscreen out of fear of the giant burning orb in the sky. Don’t just take my word for it though. If you are still concerned about the risk of too much sun exposure, here is what Reinhold Vieth, a professor at the University of Toronto, has to say about the issue. “As you head from north to south, you may find perhaps two or three extra deaths [per hundred thousand people] from skin cancer,” says Vieth. “At the same time, though, you’ll find thirty or forty fewer deaths for the other major cancers. So when you estimate the number of deaths likely attributable to UV light or vitamin D, it DOES NOT appear to be the best policy to advise people to simply keep out of the sun just to prevent skin cancer.”*
PRESCRIPTION: At least 15 to 35 minutes on most days when the sun is highest in the sky (10 a.m. to 2 p.m.), with 40% of the skin area exposed. Those with light complexions will aim to be at the lower end of the range at first, while darker complexions can be at the higher end initially.* The goal is to slowly increase sun exposure time, and to never burn. Getting sun-burnt is when problems may occur.**
*The time of sun exposure may need to be increased in the early spring, late fall or winter.
**The risks of UV radiation causing sunburn can further be reduced by increasing one’s intake of dietary antioxidants and incorporating healthy eating patterns.