Is it true that "white hair overnight" exists? Pay attention to these aspects

Author: Zhang Yu, researcher at Chinese Center for Disease Control and Prevention, master's supervisor

Reviewer: Fu Rui, Chief Physician, Beijing Century Altar Hospital, Capital Medical University

Can hair really turn white overnight? In movies, we often see scenes like this, where someone's hair turns white overnight due to a mental blow. It is said that movies are based on life, but can it really happen in real life? What factors can affect hair health?

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The phenomenon of white hair overnight is real, but it does not mean that your hair will turn white overnight. White hair is a normal physiological phenomenon. The color of hair is determined by the content of melanin particles in it. When there are no melanin particles in the hair, it will naturally turn white. But this does not mean that hair can turn from black to white all of a sudden, or reverse, because the existing melanin particles will not suddenly disappear or appear. Therefore, it is impossible to turn your hair white or black overnight, unless you dye your hair.

Why do we say that gray hair overnight is real? The melanin in the hair just mentioned is formed by melanocytes at the root of the hair. Affected by factors such as age, nutrition, nerves and hormone levels, these cells will stop or reduce the production of melanin, resulting in gray hair. Clinically, there are indeed cases where gray hair occurs due to psychological or other stimuli that reduce melanin synthesis, but most of them occur slowly. That is, the original black and white or black and gray hair becomes mainly white or gray hair. Due to the large color contrast, people have the feeling of gray hair overnight. More people have regional gray hair, especially near the temples.

How do emotions affect gray hair? There are many descriptions of emotions and gray hair in ancient poems. For example, the well-known "Song of the Wine" says, "Don't you see, the water of the Yellow River comes from the sky, rushes to the sea and never returns. The mirror in the hall sadly shows my gray hair, which was black in the morning and turned into snow in the evening." It is so magnificent. Su Shi, a writer in the Northern Song Dynasty, also wrote in "Man Jiang Hong·Waiting for Ziyou" that "I hate this life, always in separation, and my hair is gray." Coincidentally, the scenes in these poems seem to reveal the poet's emotion and lament, which shows that the matter of gray hair is not a happy thing for anyone.

In fact, negative emotions and stress such as anxiety, irritability, depression, anger, etc. will have an impact on hair health. One explanation is that it is related to endocrine disorders. Excessive or negative emotions will trigger the sympathetic nervous system and increase the release of norepinephrine. This hormone will cause melanocyte stem cells to overreact and cause premature exhaustion of melanocyte stem cells in hair follicles, thus affecting the production of melanin.

Besides emotional factors, what other factors can cause premature gray hair? Nowadays, many white-collar workers in the workplace have gray hair early on. Although they look more mature and stable, I guess everyone doesn’t like black and beautiful hair. In fact, in addition to genetic factors, it is also related to stress, staying up late and nutrient deficiency. Long-term poor rest will affect the blood circulation of the scalp and the nutrient supply of hair follicle cells. If the daily diet lacks high-quality protein, as well as trace nutrients such as iron, manganese, and copper, it may also cause changes in hair quality.

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If all these are ruled out, then you have to consider the problem of disease. For example, mottled disease characterized by congenital hypopigmentation, autosomal recessive phenylketonuria, Fanconi syndrome with proximal tubular dysfunction, autoimmune pernicious anemia, and vitiligo caused by acquired depigmentation can all cause hair to turn white. In addition, certain medications may also have an impact. Therefore, if gray hair appears, the most reliable way is to go to the hospital for a check-up.

Some people say that if you pull out a white hair, ten more will grow. Is this true? Actually, it won't. The process of pulling out white hair will not solve the problem of melanin. As long as the hair follicles are still there, the hair that grows out will still be white hair. Hair follicles are independent of each other, and each follicle will only produce one hair. Therefore, pulling out a white hair will not cause multiple white hairs to appear in the original follicle, nor will it cause the hair in other surrounding follicles to turn white. Of course, the process of pulling out white hair may cause damage to the hair follicles, and the direct consequence is that neither white hair nor black hair will grow.

In short, if you have premature gray hair, you should actively seek medical attention, find out the cause, and receive targeted treatment. Don't believe in some unreliable remedies on the Internet that may cause greater impact.