As with a lot of health advice the media tends to be very polarized when it comes to sun exposure. While Ultraviolet (UV) exposure can cause sunburn which can lead to the development of skin cancer - proper safe, sun exposure is critical for optimal health and wellness.
In addition proper UV exposure is critical for Vitamin D production which is by far the best way to optimize the many benefits of Vitamin D (See these previous blog posts on how to get safe sun exposure and supplement vitamin D in the winter: http://workoutanytime.blogspot.com/2016/08/the-facts-on-safe-sun-exposure-and.html and http://workoutanytime.blogspot.com/2019/01/how-to-optimize-vitamin-d-levels-in.html ) Also, sunlight delivers more than UV light!
Sunlight exposure has many has many other proven benefits beyond Vitamin D production including:
Sunlight kills bad bacteria on the skin and is proven to improve psoriasis, acne, eczema and fungal infections of the skin.
UVA exposure from the sun causes skin to release stores of nitric oxide which is a potent signaling molecule with many benefits including vasodilation of blood vessels that can lower blood pressure and improve erectile function. Nitric Oxide is also critical for proper immune function.
UVA and UVB exposure cause endorphin release which is relaxing and produces a strong analgesic effect helping to reduce pain. Endorphins also act as a potent anti-depressant.
Sunlight exposure early in the day is critical for proper sleep/wake cycle – sunlight signals received through the yes signal the master timekeeper in the brain, the suprachiasmic nucleus, that it is daytime and this keep time in all the peripheral “clocks” in the body so they function properly. All cells express genes that keep cellular time and regular gene expression and activity. For example skin cells exposed to UV light they expressed higher levels of two “clock” genes that control cellular circadian activity.
Decreased sunlight exposure during daytime negatively affects circadian rhythms and night-time melatonin production so while night-time exposure to light (and blue light in particular) decreases melatonin secretion – daytime exposure (particularly early morning after first waking up) increases it later in the night!
The infrared rays of the sun penetrate the skin deeply producing many benefits including:
Helps reduce blood pressure
Helps prevent sunburns – so early morning sun exposure (when there is a high percentage of Infrared and reduced UV) can paradoxically help prevent sunburn later in the day.
Reduces pain and stiffness – this a very real benefit which is why you see animals like cats sit in the sun and stretch!
So enjoy safe sun exposure every day to reap these many benefits. The key is pre-burn exposure. Morning sun exposure (prior to 11am is very safe in most locations) and will greatly improve circadian rhythms and sleep while mid-day exposure is key for Vitamin D production. To learn how to get safe sun exposure read the two previous blog posts mentioned above.