Why Does Gray Hair Appear?

If gray hair appears, it is because physical and chemical processes have been triggered by which the hair loses its natural pigment. However, several investigations are currently underway and could lead to the reversal of this process in the years to come.

Graying is inevitable, at least for most humans. This is a completely natural biological process. This is why we usually don’t ask ourselves why gray hair appears and if it is just due to age or other factors.

The question has much more impact on aesthetics than on biology. For the same reason, many people are terrified when they see their gray or white hair stick out and try to hide it. Others, on the other hand, dye their hair gray before it appears.

It should be noted that the probability of graying increases by an additional 10-20% for each decade of life, starting at age 30. But there are young people who turn gray much earlier than that. What is behind all this? Let’s see this together.

The appearance of gray hair

Gray hair is white hair that generally appears gradually with age. However, it should be noted that before birth, at the beginning of life, everyone has white hair. During the formation process, the hair acquires other shades thanks to a substance called melanin.

There are two types of melanin: eumelanin, which gives color to dark hair; and pheomelanin, which gives color to fair hair. Sometimes the two are combined and give birth to other hair tones like chestnut, red, etc. Melanin is formed in cells called melanocytes, the function of which is to produce pigments to color hair.

When gray or white hair comes out, it means that the melanocytes are no longer producing pigment. It can happen at any age, but it’s very rare in people under 20. If this occurs before the age of 30, it is called “precocious caniosis”. If this occurs after the age of 30, it is called “physiological caniosis”.

Why does gray hair appear?

There is a lot of talk about why gray hair appears. However, science has only been able to identify two fully proven causes. Those are :

• Genetics : Although the genes responsible for this process have not been identified, genetics are known to play a decisive role. Among other things, it determines the age at which gray hair grows. More premature graying occurs in Caucasians and Asians
• Diseases : pathologies such as vitiligo cause loss of pigment that gives hair color. So-called “pernicious” anemia, lack of vitamin B 12, hypothyroidism and Werner’s syndrome have a similar effect.

It has been suggested that there are other factors that promote or accelerate the graying process. It is not entirely proven to be the case, but there are indications of their influence. Here they are :

• Stress : The alteration of metabolism and hormones caused by stress, could have some impact on the production of melanin. People who go through difficult situations repeatedly tend to get intoxicated more quickly
• Unbalanced diet : low intake of antioxidants and vitamins and minerals has been suggested to impact graying
• Toxins : Some people think that smoking and ingesting alcohol and other drugs make hair graying. However, there is no strong evidence that this is the case.

New data

A group of German scientists conducted research which concluded that the low production of melanin is due to the excessive presence of hydrogen peroxide in the hair cells. The way to avoid this is to eat foods high in catalase, like avocado, leek, onion, calf’s liver, etc.

On the other hand, Professor Desmond Tobin, of the University of Bradford (UK), concluded that in the follicle of the hair root there is a kind of “biological clock”. This determines when the melanocytes stop making the hair pigment. What is new is that there is evidence that this process can be reversed.

At the same time, a study carried out at the University of Cairo (Egypt), under the direction of Professor Irini Samuel, pointed out that, in the case of men, there is a link between the graying process and the risk of coronary heart disease. A high level of gray hair, at an early age, would be a sign of this risk.