The pinkish melanin travels up through the epidermis and is absorbed by the outer skin cells . When UVB rays strike the melanin the skin oxidizes , or darkens .

This darkening , or “tanning” , is your skin’s way of protecting itself from too much UV light – in fact , a tan is a symptom of UV overdose ! The outer skin is continually sloughing “old-dead” cells, replacing them with “new – dead” cells daily; this is why a tan “fades” .

However the extra melanin in tanned skin only provides a Sun Protection Factor of about 2 to 4 , far below the desired minimum SPF of 15 .