Causes & formation of grey hair

Research has discovered: people whose hair turns grey are suffering from oxidative stress in the hair follicle and the pigment-forming cells (melanocytes). This oxidative stress in the hair roots is acutely triggered by an accumulation of hydrogen peroxide. The reason for this accumulation is largely genetic. This means we have a genetic predisposition for this. In addition, external factors such as illnesses or smoking can increase the risk of oxidative stress. A certain formation of hydrogen peroxide is normal in the body cells as it is a metabolic by-product. In healthy, relaxed, younger bodies, certain enzymes (catalases) rapidly break hydrogen peroxide down again into water and oxygen, and it doesn’t cause any noticeable damage. In people whose hair turns grey their hydrogen peroxide concentration is higher than normal. Mostly there is a lack of those enzymes (catalases) that are responsible for the breakdown of hydrogen peroxide. Too much hydrogen peroxide impedes the functioning of the enzyme tyrosinase, which is vital for colour pigment formation. Hydrogen peroxide thus blocks the natural formation of melanin, (the hair’s colour pigment). The consequence: Step by step, the hair increasingly fades and turns grey or white. Find out more here on how and whether you can prevent the formation of grey hair.

The lack of reproduction of colour pigments (melanin) causes an increasing decline of their number in the hair’s fibrous layer (cortex) until the hair turns white or colourless. Aging and cell damage due to oxidative stress not only result in a loss in colour pigment, but often also to limitations in other metabolic processes. This can result in a loss of hair mass, lipids and proteins. The hair not only loses its colour brilliance, elasticity and stability. In addition, it experiences a change in its physical properties.

Human hair is formed in the hair follicle. Laypeople also call the hair follicle the hair roots. The cells that are responsible for hair growth are called the keratinocytes. They form keratin, a fibrous protein, the main substance that hair consists of. In the hair follicle, between the keratin-forming cells, there are also the cells that are responsible for our hair colour. These pigment-forming cells are called melanocytes. These melanocytes form two different pigments: Eumelanin, a black and brown pigment, and phaeomelanin, a red and golden pigment. The number and mixing ratio of these two pigments (melanins) define the individual natural hair colour, colour depth and colour reflex. The more black and brown pigment (eumelanin) the hair contains, the darker the hair. Both colour pigments are deposited in the hair mass, to be precise in the fibrous layer (cortex), of the hair. To form the melanins the body’s own amino acids are converted to coloured pigments in the melanocytes. The amino acid tyrosine and the enzyme tyrosinase play a key role in this conversion. If a building block is missing, the natural pigment formation is impaired.