The dye’ that gives our skin, eyes and hair their colour is melanin. This chemical is constantly produced by pigment cells called melanocytes. A person’s complexion is determined by the functioning of the melanocytes and the type of melanin they produce.
Each hair on our head is made up of two parts – a shaft, which is the coloured part, and a root, which keeps the hair anchored to the scalp. The root of every strand of hair is surrounded by tissues called hair follicles. These follicles contain the pigment cells, which give our hair and skin their colour (Related cells are also found in the eye, producing pigment for the iris.) Getting grey hair is a natural part of growing old. As we get older, the pigment cells in the hair follicles gradually die. When there are fewer pigment cells in a hair follicle, that strand of hair will no longer contain as much melanin to produce colour. Hence the hair turns grey. However, people can get grey hair at any age. This is determined by our genes.
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