For a long time, there has been a certain misunderstanding and confusion about the relationship between gray hair and cancer risk.
Some middle-aged people are troubled by the appearance of gray hair, and there is a belief circulating in society that gray hair may be associated with a lower risk of cancer. The popularity of this view stems in part from a misreading of scientific research and inaccurate media coverage.
The relationship between gray hair and cancer
To be clear, the often cited research to support the association between gray hair and reduced cancer risk was not conducted by Harvard University. In fact, the study originated in 2009 with an experiment on mice conducted by researchers in Japan.
The experiment found that in the case of DNA damage, melanocytes in mice are transformed into mature melanocytes, resulting in changes in hair color.
This finding focuses on revealing the biological mechanism of gray hair, and does not directly explore the relationship between gray hair and cancer risk.
However, the interpretation of this study has been misinterpreted by media reports, particularly in the British Daily Mail. The report cites the interpretation of the study by the director of the Department of Dermatology at Harvard University, suggesting that the biological mechanism of gray hair turning gray may be related to reducing the risk of cancer.
This interpretation is actually a discussion of whether melanocytes continue to exist in stem cell form or the impact on the body of melanocytes, and does not directly compare the cancer risk of people with black hair with those with gray hair.
Therefore, there is currently insufficient scientific evidence to support a direct causal relationship between gray hair and reduced cancer risk.
Gray hair is more of a natural manifestation of aging, and is related to a variety of factors such as genetic factors, lifestyle, environmental factors, etc.
Various causes of gray hair
Gray hair is a common phenomenon and its causes are complex and varied, including genetics, diet, mental, age and environment.
Genetic factors play an important role in the formation of gray hair. There is often a clear family history of the so-called lack of whiteheads, and if one of the parents has gray hair early, the child is more likely to have the same condition.
This genetic predisposition means that in some families, gray hair may appear at an earlier age than in the general population.
Dietary factors also have a significant impact on hair color. Malnutrition, especially long-term deficiencies in nutrients such as protein, B vitamins (such as vitamins B1 and B2), zinc and copper, can affect the normal growth and pigmentation of hair, thereby accelerating the appearance of gray hair.
Proper supplementation with these nutrients can help maintain normal color and healthy hair.
Mental stress is also an important factor in hair color. Long-term exposure to anxiety, depression, nervousness, insomnia, and other adverse mental states can affect the normal physiological functions of the body, including the activity of melanocytes, which may lead to the early appearance of gray hair.
Therefore, maintaining a good state of mind, proper relaxation and rest has a positive effect on delaying the formation of gray hair.
Age is an irreversible natural factor that affects gray hair. As we age, hair follicles naturally age, and the activity of melanocytes gradually decreases, causing the hair to gradually lose its color and eventually turn into gray hair.
Although it is not possible to stop aging, with a healthy lifestyle and balanced nutrition, the aging process of hair can be slowed down to a certain extent.
The possibility of gray hair reversal
In a study conducted in the lab of Xu Yajie at Harvard University, Dr. Zhang Bing and his team revealed the exact mechanism by which stress causes hair to turn gray, published in the journal Nature on January 22, 2020.
研究标题为“Hyperactivation of sympathetic nerves drives depletion of melanocyte stem cells”，揭示了压力通过激活交感神经系统，对毛囊中的色素干细胞造成永久性损害的过程。
Within the hair follicle, pigment stem cells are the source of pigment cells, which are converted into pigment-producing cells during hair growth, giving hair its color.
The research team found that norepinephrine released by sympathetic nerves under stressful conditions leads to overactivation of pigment stem cells and rapid transformation into pigment-producing cells.
This process leads to the premature depletion of stem cell stocks, which affects the pigment-producing capacity of hair follicles.
Commenting on the findings, Dr. Xu said: "When we started working on this topic, we already foresaw that stress would cause some kind of damage to the body. However, we found that the extent of this impact was far greater than we expected. Within just a few days, all the pigment stem cells in the hair follicles disappear, and once these cells are gone, the hair follicles can no longer produce pigment. This damage is permanent. ”
This study not only provides a scientific basis for what is commonly referred to as "stress makes hair gray", but also reveals the specific physiological mechanisms behind this phenomenon.
By understanding how stress affects the body's specific physiological processes, we can place more emphasis on stress management and take appropriate measures to mitigate its negative effects on the body.
在美国哥伦比亚大学的一项研究中，科学家们探讨了压力与头发变白之间的关系，并在2021年6月22日的《eLife》期刊上发表了题为“Quantitative mapping of human hair greying and reversal in relation to life stress”的研究论文。
This study not only revealed the phenomenon of stress-induced hair graying, but also found that hair color has the potential to recover after stress is reduced.
The research team recruited 14 volunteers who kept their own "stress diaries" through which they reviewed their stress experiences and assessed their stress levels each week.
The researchers collected hair samples from these volunteers and cut them into small pieces for detailed analysis to determine the extent of the graying of the hair.
The hair samples were about 1/20 millimeter wide in each section, equivalent to an hour of hair growth, a meticulous division that allowed the researchers to accurately track changes in hair color and compare them to pressure changes on a time scale.
Using a high-resolution scanner, the researchers observed and measured subtle color changes in the hair. When they contrasted the change in hair color with the volunteers' stress diaries, they found a strong link between stress and graying of the hair.
The results of the study show that as an individual's stress levels decrease, the process of hair graying is not only alleviated, but in some cases even reversed.
It demonstrates a direct correlation between stress and graying of hair, and shows that certain physiological changes are reversible when life stresses are reduced.
With effective stress management, not only can an individual's psychological state be improved, but it may also have a positive impact on physical appearance, especially in the process of controlling and reversing hair graying.
Environmental factors have an impact on the formation of gray hair
Environmental factors play a role that cannot be ignored and can have a significant impact on the health and color of your hair.
Prolonged exposure to UV rays is one of the main environmental factors that accelerates hair graying. UV rays can damage the protein structure in the hair, especially melanin, which is a key factor in determining hair color.
With the loss of melanin, the hair will gradually lose its original color and become gray. In addition, air pollution is also an important environmental factor that contributes to gray hair.
Harmful substances in the air, such as sulfur dioxide, nitrogen oxides and tiny particulate matter, can penetrate the scalp and hair follicles, affecting the normal function of melanocytes, thereby accelerating the formation of gray hair.
The impact of chemicals should not be overlooked. Frequent use of hair dyes and other hair care products that contain strong chemical ingredients can cause damage to the scalp and hair follicles, affect the health of melanocytes, and accelerate the appearance of gray hair.
Acid rain in nature, because it contains harmful substances such as sulfuric acid and nitric acid, can also cause damage to the hair and affect the hair color.
In addition to the above-mentioned factors, other environmental factors in life, such as exposure to harmful bacteria and pollutants, may also have adverse effects on hair health, leading to the formation of gray hair.
Therefore, in order to slow down the formation of gray hair, it is crucial to take some protective measures. Try to avoid prolonged exposure to strong sunlight and protect your hair by wearing a hat or using UV-blocking hair products when you go outside.
Minimize the amount of time spent in environments with high levels of air pollution and use air purifiers to reduce indoor air pollution. In addition, choosing hair care products with natural ingredients and avoiding hair dyes that contain strong chemicals can reduce chemical damage to your hair.
Prevention strategies for gray hair
The appearance of gray hair is influenced by a variety of factors, including physiological factors, diseases, and mental states.
While gray hair in older adults is primarily a result of natural aging, in some cases, the formation of gray hair can be prevented or slowed down by adopting an active lifestyle and health management measures.
Gray hair due to aging is a common physiological phenomenon in the elderly. As we age, the activity of melanocytes in the hair follicles gradually decreases, causing the hair to gradually lose color and turn white.
While this process is natural and cannot be avoided entirely, it can be slowed down through healthy lifestyle habits.
For example, avoiding smoking is an important recommendation, as the harmful substances in tobacco not only cause damage to lung health, but may also accelerate the overall aging process, including the appearance of gray hair.
Certain diseases can also cause gray hair to appear prematurely. For example, diseases such as vitiligo, alopecia areata, and pernicious anemia can cause malnutrition in the body, which in turn can affect hair color.
Prompt and effective treatment of these diseases is essential not only for the disease itself, but also for preventing or reducing the formation of gray hair.
If gray hair is associated with a specific health problem, it is essential to seek the advice of a medical professional and treat it appropriately.
Mental factors also have an important influence on the formation of gray hair. Long-term stress, tension and anxiety can lead to physiological changes that affect the function of melanocytes and accelerate the process of hair graying.
To mitigate this effect, appropriate stress management methods such as listening to soft music, engaging in regular physical activity, practicing meditation or yoga are recommended, which can help reduce stress, promote mental relaxation, and indirectly slow down the appearance of gray hair.
In addition, a sensible diet also has a positive effect on the prevention of gray hair. Make sure you're getting enough protein, vitamins (especially B vitamins), minerals such as zinc and copper, all of which play an important role in maintaining healthy hair and color.
Avoiding nutritional imbalances or picky eating and maintaining a balanced diet can help maintain the natural color and overall health of your hair.
References are as follows:
【1】uantitative mapping of human hair greying and reversal in relation to life stress
【2】Hyperactivation of sympathetic nerves drives depletion of melanocyte stem cells