'It is well known that gray hair results from a reduction of pigment, while white hair has no pigment, but why this happens remains somewhat of a mystery.

Parents often cite having teenagers as the cause of gray hair. This is a good hypothesis, but scientists continue to investigate why hair turns gray. In time, everyone’s hair turns gray. Your chance of going gray increases 10-20% every decade after 30 years.'

The age at which you'll get your first gray hair (assuming your hair doesn't simply fall out) is largely determined by genetics. Every hair follicle contains pigment cells called melanocytes. The melanocytes produce eumelanin, which is black or dark brown, and pheomelanin, which is reddish-yellow, and pass the melanin to the cells which produce keratin, the chief protein in hair. When the keratin-producing cells (keratinocytes) die, they retain the coloring from the melanin. When you first start to go gray, the melanocytes are still present, but they become less active.

Hair colour is produced by cells known as melanocytes, which migrate into the hair bulb as the hair follicles develop in utero. The melanocytes produce pigment that is incorporated into the growing hair fibres to produce hair in a bewildering array of natural shades.

Hair colour depends on the presence and ratios of two groups of melanins: eumelanins (brown and black pigments) and pheomelanins (red and yellow pigments). While variations in the ratio of these pigments can produce an large number of colours and tones, siblings often have strikingly similar hair colour.

Hair colour varies according to body site, with eyelashes being darkest because they contain high levels of eumalanin. Scalp hair is usually lighter than pubic hair, which often has a red tinge, due to the presence of more phaeomelanin pigments. A red tinge is also common in underarm and beard hair, even in people with essentially brown hair on their scalp.

Parents often cite having teenagers as the cause of gray hair. This is a good hypothesis, but scientists continue to investigate why hair turns gray. In time, everyone’s hair turns gray. Your chance of going gray increases 10-20% every decade after 30 years.

Initially, hair is white. It gets its natural color from a type of pigment called melanin. The formation of melanin begins before birth. The natural color of our hair depends upon the distribution, type and amount of melanin in the middle layer of the hair shaft or cortex.

Hair has only two types of pigments: dark (eumelanin) and light (phaeomelanin). They blend together to make up the wide range of hair colors.

Melanin is made up of specialized pigment cells called melanocytes. They position themselves at the openings on the skin’s surface through which hair grows (follicles). Each hair grows from a single follicle.