Firstly, there is no such thing as grey hair. The correct term should be white hair. It is the light reflection that gives the appearance of grey hair. The following outlines the two main white hair conditions:
Albinism – a recessive hereditary condition which presents as white hair & skin which in incapable of tanning. Caused by the total disfunction of tyrosinase (enzyme) preventing melanin production, thought to be be caused by a mutation within the genetic structure. Albinos therefore have no colour production capabilities and subsequently do not tan or produce hair colour.Although the skin tends to appear paler, it is otherwise normal. Albinism affects people from all nationalities, showing no affilation to sex. The eyes are also affected turning colourless and white.
There are two types of colour pigment within the hair and skin namely:
Eumelanin – responsible for dark colours such as brown and black
Pheomelanin – responsible for lighter colours such as red and yellow
Each of us tend to have a mixture of the above however, one type may be dominant.
Tyrosinase – is the major enzyme responsible for the formation of Melanin pigment viz: Tyrosine > DOPA >Dopaquinone > Eumelanin or Pheomelanin. In normal skin a suntan occurs when melalin (which absorbs the suns ultraviolet radiation) pigment (produced from melonocytes) increases in the skin due to increased exposure to the sun.
If you are suffering from any form of hair change, hair loss or scalp condition, please feel free to contact our help line. You will be able to speak with a trichologist who will be happy to advise you.
Canities ( referring to the whitening (greying) of hair) –presents as white hair caused by a pigment deficiency frequently seen during the 3rd and 4th decade. Shows no affiliation to sex. The hair itself is white. The grey appearance is an illusion caused by the presence of surrounding pigmented hairs. A single grey hair often glistens resembling shot silk & reflects the colour’s of its immediate surroundings. In many people canities precedes the development of snow-white hair in later life. This gradual reduction of pigment may well be accompanied by hair shaft thickening or thinning. Genetic influences is the most likely cause. Canities primarily effects the anterior parietals. This will progress over the vertices eventually effecting the occiput. Beard hair tends to be first to lose colour pigment. Axillary and pubic hair tends to becomes depigmented later in life. However, it is not always effected.