I believe that there are not many people who like to have gray hair. In particular, many middle-aged people, and some young people who have gone bald prematurely, will always complain that gray hair has affected their personal image, which is very troubled, even if there are only a few gray hairs, it seems to look particularly eye-catching on the head.
Many people can't help but ask, after the hair turns white, can it be black again?
If you want to answer simply, the answer is - it can come back black, such as dyeing hair.
But you may not be satisfied with this "jitter" answer and want to know more about the treatment. So today we will carefully comb the black and white hair.
The principle of hair color change
The color of the hair is determined by the pigment in the hair, which is mainly melanin, or melanin for short. Black hair has more melanin, white hair has little or no melanin, and gray hair is somewhere in between.
Black hair (left) and white hair (right) (from references)
The production process of melanin is like a complex production line, which is affected by various links, such as race, genetics, individual differences, diseases, age, and so on.
So, why does hair turn from black to white? In a word, the root cause is the dysfunction and cell death of melanogenic melanocytes in the hair follicle pigment unit.
That is, a specific melanocyte malfunctions, or dies directly, which is like a chicken that is sick or dead, so there are no eggs.
Many other cells also play an important role in this process, especially melanocyte stem cells, which have the ability to "create something out of nothing", that is, differentiate and transform into new melanocytes. Due to factors such as aging, these stem cells become "lazy", their ability to transform decreases, and gray hair will become more numerous. In case of complete loss of stem cells, then gray hair will never be able to turn black.
In addition, the epithelial stem cells in the hair follicle will also be inserted, and its progeny cells provide a breeding ground for the stem cells that grow melanocytes, and if the progeny cells are depleted for some reason, the hair will also turn gray.
In addition to the effects of stem cells, there are quite complex mechanisms at the molecular level.
What makes hair gray?
After understanding the basic principles of hair color change, let's talk about why some people have gray hair when they are not very old. In fact, from the perspective of etiology, there are no more than two categories of causes:
Physiological causes: such as old age, family inheritance;
Pathological causes: e.g. skin and hair diseases, drug effects.
People with gray hair can be divided into "ordinary gray hair" and "premature gray hair" according to their age. Asians begin to have gray hair in their 30s, which is "common gray hair", and many people have half a head of gray hair at the age of 50. Ordinary gray hair is generally a normal sign of aging. "Premature gray hair" refers to gray hair at or before the age of 25, 10 years or more earlier than the average gray hair population.
For most people (including premature gray hair), the main cause of gray hair is physiological. Some scholars have analyzed the data of 467 people with "premature gray hair" (354 women, 113 men), ranging in age from 18 to 77 years old. It was found that:
Premature gray hair is closely related to family history, whether it is father, mother, grandparents or siblings, which suggests that genes are powerful;
If you are deficient in iron, you are also more likely to have gray hair;
If you are a man, oral biotin supplements are more likely to have gray hair.
In addition to this, studies have also found that there is no definite association between premature graying of hair and obesity, alcohol consumption, coffee consumption, stress, bad mood, or immune diseases.
It has to be said that this study has quite a few counter-intuitive results. For example, it is widely believed that emotional stress can cause gray hair, but so far, there is no definitive research to confirm a causal relationship between stress and gray hair.
In addition, some people may be superstitious that the use of health supplements and nutrients will improve the condition of hair, but blindly and unfounded use of such products may be counterproductive, because the above suggests that men are more likely to develop gray hair if they take biotin supplements orally.
So, how can you tell if you have sick gray hair?
If you are of the right age (around 30 years old or older), occasionally have a few strands of gray hair, and the texture, skin texture, and pigmentation on the face are slowly revealed, then there is basically no need to worry about other problems.
If the hair turns gray in a short period of time, or if it is accompanied by symptoms such as hair loss or graying of the scalp, or if there are skin and extra-skin manifestations, it may be due to a disease. At this time, it is recommended to seek medical attention offline to see if there are any other problems. The above manifestations may be manifestations of alopecia areata (commonly known as ghost shaving), telogen effluvium, vitiligo, medical diseases, drug reactions, etc.
How do you turn gray hair black?
So is there a way to make gray hair black? There are several practical ways to do this.
1
Hair coloring
Although hair coloring is not a medical treatment, it is indeed a way to darken and have an immediate effect. This suggestion is not a whimsical move, but a desperate move - although scientists have found some promising drugs, no blackening drugs have been approved as effective so far.
2
Pull out or cut off
Pulling out gray hair can theoretically remove gray hair, and in addition, there is no need to worry about pulling one to ten long. However, there is a risk of damaging hair follicles and increasing the chance of infection.
Rather than pulling the hair roughly, cutting the gray hair at the roots is preferable because it does not damage the hair follicles. The downside is that gray hair only keeps you out of sight and out of mind for a short time, and after a while it will grow back.
3
Prompt treatment of related diseases
Some gray hair is caused by diseases, such as alopecia areata and vitiligo, so the focus of treatment should be on the original disease, and after the disease is cured, there is hope that the gray hair will also improve.
bibliography
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[2] The depigmentation of white hair. https://www.nccreation.ch/en/cure-of-melanin-in-an-other-solution-for-your-white-hair/
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[4] Feng Z, Qin Y, Jiang G. Reversing gray hair: Inspiring the development of new therapies through research on hair pigmentation and repigmentation progress. Int J Biol Sci. 2023; 19(14): 4588.
[5] Thompson KG, Marchitto MC, Ly BCK, et al. Evaluation of physiological, psychological, and lifestyle factors associated with premature hair graying. Int J Trichology. 2019; 11(4): 153.
[6] Webmd. Facts About Gray Hair. https://www.webmd.com/beauty/ss/slideshow-beauty-gray-hair-facts. Nov 15, 2021.
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(Source: Popular Science China Author: Tang Jiaoqing, Attending Physician of Dermatology, MD)