The solar spectrum is made up of electromagnetic rays, of variable energy and wavelength. They penetrate the skin, causing not just positive, but also negative effects.
While UVB rays affect the epidermis, UVA rays penetrate more deeply into the dermis and infra-red rays penetrate down to the hypodermis, or subcutaneous tissue.
UVB Ray Plus Points: Essential for the synthesis of vitamin D, which is needed for growth, these are also the tanning rays.
UVB Ray Minus Points: Responsible for sunburn, they can cause cellular mutations and cancer.
UVA Ray Plus Points: Give an immediate, but temporary colour and glow.
UVA Ray Minus Points: Generate free radicals, which can cause alterations in the skin cells and support fibres, causing sun aging.
Infrared Ray Plus Points: Give a lovely warming feeling.
Infrared Ray Minus Points: Can dry the skin out.
Photo: Garnier Ambre Solaire