What we know about the effects of UV light exposure on the human body
(from Juzeniene A and Moan J. Beneficial effects of UV radiation other than via vitamin D production. Dermato Endocrinology, 2012.)
Enhances mood and energy. tanners commonly report feeling more relaxed than non-tanners. One study demonstrated that β-endorphins increase after UV exposure, which would explain this association.
Treats skin diseases. These diseases include treatment of lupus vulgaris, psoriasis, vitiligo, atopic dermatitis and localized scleroderma.
Ultraviolet light reduces inflammation in the ski.(Psoriasis Association 2016).
Ultraviolet light directly reduces itch and has an anti-inflammatory effect (National Eczema Association 2016).
Relieves pain in fibromyalgia. UV exposure seems to have potential to reduce pain in patients with fibromyalgia compared to no exposure.
Skin barrier functions. Skin exposed to UVB and UVA is more resistant to primary irritants.
Protects from disease beyond vitamin D? In an animal model, researchers discovered that UV exposure is more protective and suppressive against multiple sclerosis than just vitamin D alone.
Better sleep. It is believed that the more light one is exposed to during the day, the sooner melatonin production occurs at night. Melatonin is involved in the sleep-wake schedule and when released, makes the body drowsier and cooler.
Prevention of Osteoporosis
(from Arthritis Foundation of Western Australia)
Vitamin D is essential for bone health, because it helps:
Increase the absorption of calcium and phosphorous from the stomach
Regulate the amount of calcium in the blood
Strengthen the skeleton.
To get enough sunlight to produce vitamin D, a person needs to expose their hands, face and arms (around 15% of body surface) to sunlight for about 6 - 8 minutes, 4 - 6 times per week for moderately fair people).
Older people need exposure to sunlight 5-6 times a week. Dark skinned people need longer exposure times of around 15 minutes.