The Science

About Ultraviolet (UV) Rays*

Ultraviolet (UV) light is electromagnetic radiation present in sunlight and other sources

3 different types of UV rays

UVA:

  • The longest wavelength

  • Reaches deep into the layers of skin causing aging, wrinkling, loose skin and sun spots

  • Sometimes can affect DNA, which increases risk of skin cancer

UVB:

  • Has largest effect on top layer of skin

  • Causes redness, burning, skin cancer

UVC:

  • The shortest wavelength

  • Absorbed by the atmospheric ozone and usually do not affect skin

* SunGrubbies

 

UVA UVB

 

UV Exposure - Benefits and Risks

UV exposure is not that bad. It helps to produce vitamin D that our bodies need and which is important for the immune system. The problem occurs when you you are exposed to too much sun.

BENEFITS

 Risks

  • Production of Vitamin D - Strengthen bones, muscles and the body’s immune system.

  • Mood Improvement - The creation of serotonin is promoted by vitamin D. Serotonin level changes affect mood and behavior.

  • Helps some skin conditions – With moderate phototherapy, successful treatment of eczema, dermatitis, rickets, atopic and localized scleroderma, jaundice, and psoriasis is possible.

  • Skin cancer – Research shows that as many as 90% of skin cancers are due to UV over exposure.

  • Sunburn - The long-term effects of sunburn include premature wrinkling and an increased risk of skin cancer, including melanoma (the most dangerous type of skin cancer.

  • Damaging the immune system – by having a suppressing effect on the immune system

  • Damaging the eyes – e.g. snow blindness (photokeratitis), cataracts and other diseases.

  • Aging the skin – wrinkles, brown "liver" spots, loss of elasticity by destroying collagen and connective tissue beneath the top layer of the skin.

The key to a safer time out in the sun is to avoid sunburn

  • Know strong the UV radiation is at any given moment

  • What that means for your skin type.

 

Sources

Healthline - The Benefits of Vitamin D

Vitamin D Deficiency. N Engl J Med 2001: 357: 266-281

Skin Cancer Foundation

US Surgeon General

World Health Organization