“My hair turned white overnight”, can it turn black again?

Do you still remember the popular drama "Kuang Biao" some time ago? In the drama, the male protagonist An Xin suffered a strong mental blow due to the sacrifice of his comrade Li Xiang, and his black hair turned white a few years later. From ancient times to the present, there are many sayings about "white hair overnight". In ancient times, Wu Zixu's hair turned white overnight when he passed Zhaoguan. Today, there are cases in social news where parents' hair turned white overnight because their children were seriously ill. So is "white hair overnight" true or fictional?

Wu Zixu

Source｜TV series stills

1

Why does hair turn white?

To understand why people's hair turns white, we must first talk about why hair is black.

The color of hair is mainly determined by the presence of eumelanin and pheomelanin in the hair of the scalp. Eumelanin generally makes the hair appear black or brown, while pheomelanin causes the hair to turn red or yellow. Therefore, the combination of the two melanins in different proportions will result in different hair colors, and the mixing ratio is mainly determined by genetic genes.

So what is the principle of black hair turning white? There are many factors that affect hair whitening, the most important of which is "aging of pigment cells". As we age, pigment stem cells and melanocytes gradually decrease, which affects the hair's absorption of melanin , causing the hair to turn white.

Source: Internet

In addition to aging, the following factors can also accelerate melanocyte aging:

・Disease factors : vitiligo, premature aging syndrome, abnormal thyroid function, etc.

Vitiligo symptoms

Source: Medical Encyclopedia

・Lack of trace elements : iron, calcium, vitamin B12 and vitamin D

・Mental factors : excessive mental stress for a long period of time, extreme sadness, or excessive mental use for a period of time

・Genetic factors : The appearance of a large amount of gray hair before the age of 25 is collectively called "premature graying", which has the prominent characteristic of family inheritance.

・Bad lifestyle habits : smoking, alcoholism, obesity, staying up late, etc.

・Exposed to ultraviolet rays for a long time

2

What is the reason for “white hair overnight”?

In fact, for a long time, the saying of "turning hair white overnight" had no scientific basis, until a study by a Harvard University team gave this so-called "folk legend" a certain scientific basis.

In 2020, a research team from Harvard University published a research report titled "Hyperactivation of sympathetic nerves drives depletion of melanocyte stem cells" in Nature. The report, through a study on the relationship between melanocyte stem cell depletion in mice, proved for the first time that mental stress also has some relationship with gray hair .

How to make mice feel stressed is a difficult point in the experiment. So the researchers injected the mice with capsaicin analogs. We know that spiciness is a kind of pain, and pain can cause mental stress to a certain extent. Sure enough, within five days, the mice's hair turned white.

Experiments have shown that after injecting capsaicin analogs, the mice's hair turned white

Source | "Hyperactivation of sympathetic nerves drives depletion of melanocyte stem cells. Nature"

Researchers further discovered that extreme emotions such as stress can also stimulate the sympathetic nervous system, causing the sympathetic nerves to release a large amount of norepinephrine. Norepinephrine can cause melanin stem cells to proliferate abnormally and rapidly, then differentiate into special pigment cells and migrate, and finally permanently lose them. When all melanin regeneration stem cells are exhausted, pigment can no longer be generated, and the hair will turn completely white.

In addition, the symptoms of "white hair overnight" may also be related to pathological reasons, namely acute diffuse alopecia areata . Acute diffuse alopecia areata is closely related to immunity. Great mental stress will make the hormone level in the body extremely unstable, induce immune response, and cause the immune system to mistakenly attack the black hair follicles, causing them to enter the resting phase, causing the black hair to fall off faster , so that the white hair accounts for a larger proportion visually, showing "white hair overnight". So "white hair overnight" in this case does not mean that all black hair turns white, but that the black hair falls off, highlighting the existence of white hair.

Source: pixabay

Huang Shujiang, deputy chief physician of the Department of Dermatology at Guangdong Provincial People's Hospital, explained that "white hair overnight" is actually relatively rare and the probability is low. It is more likely to be caused by diseases such as vitiligo and diffuse alopecia areata. It is important to seek medical attention in time and seek help from a dermatologist.

3

Is it true that the more you pull out your white hair, the more it will appear?

There is a popular saying among the people that "the more you pull out your white hair, the more hair you pull out." Is there any scientific basis for this?

In fact, white hair can be pulled out in moderation, and there is currently no relevant scientific research showing that pulling out white hair will make the number of white hair increase, because pulling out white hair only ends its "life" prematurely and will not affect other hair.

However, it should be noted that you should try to use scissors to cut off white hair, because forceful removal will cause certain damage to the hair follicle where the white hair is located, and may cause folliculitis in severe cases, making it increasingly difficult for subsequent hair to grow, and in the end you will end up with a tragic ending of "white and bald".

Source: pexels

Many friends are also concerned about whether the hair can turn black again after turning white overnight. Researchers said that if the pigment stem cells are not completely lost, the adjacent normal pigment cells may be able to remedy the hair follicles lacking pigment cells, thus turning the gray hair black again.

Therefore, friends should pay more attention to their own mood, relax and relieve stress appropriately. After all, nothing is more important than good health.