What are UV rays?

Temperature does not dictate the amount of UV emitted from the sun. This means that on a sunny winter's day you can still get sunburned.
UV radiation is part of the electromagnetic (light) spectrum that reaches the earth from the sun. There are 3 classifications of UV light: UVA, UVB, UVC.
The short rays of UVC are absorbed by the ozone layer and do not reach the earth, however UVA and UVB rays penetrate the atmosphere and play an important role in premature ageing, uneven skin and skin cancers.
UVA is the longest of the 3 rays at 320-400nm. These rays can penetrate through clouds, windows and into the dermis. Prolonged exposure shrinks collagen and elastin fibers and causes fine lines, wrinkles and loss of elasticity.
UVB rays range from 290-320nm. Their intensity varies depending on location, time of the day and time of the year. These rays penetrate the epidermis stimulate melanin and can result in freckles, mottled and uneven complexion as well as redness and sunburn.
In additional to accelerating the ageing process all UV exposure can suppress the skin's immune system and increase the risk for skin cancer. So it is imperative that your daily skincare regimen include a broad spectrum sunscreen to block damage from both UVA and UVB rays as well as potent antioxidants to protect against free radical damage.

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