New Insights into Gray Hair: It's Not Just Aging
A recent study from New York University suggests that gray hair in middle-aged and older adults might not be solely due to aging and the depletion of pigment stem cells. Instead, these cells may be "stuck." This raises the possibility of reversing gray hair if these stem cells can be repositioned.
The 50-50-50 Rule and Variations in Graying
Research indicates a "50-50-50 rule": 50% of people have 50% gray hair by age 50. However, the onset of gray hair varies across different ethnicities.
-
Caucasians typically start graying around age 35.
-
Asians around age 40.
-
Africans around age 45.
Premature graying, occurring before age 20 in Caucasians, 25 in Asians, and 30 in Africans, is often linked to genetics.
Stress and Gray Hair: The Anecdotal Evidence
Historical anecdotes, like Marie Antoinette's hair turning white the night before her execution, and the story of Wu Zixu from the Spring and Autumn period in China, suggest that extreme stress can contribute to hair graying. Even modern figures like Barack Obama have shown significant hair color changes due to the pressures of their roles.
The Role of Stem Cells in Hair Color
Hair growth involves two key types of stem cells:
-
Follicle stem cells: responsible for creating hair.
-
Pigment stem cells: responsible for adding color to the hair.
When pigment stem cells become depleted or unable to produce melanin, new hair grows in white. This is analogous to a printer running out of ink.
The Impact of Stress: A Case Study
A study by researchers in Columbia showed a correlation between stress and hair color. In one instance, a 30-year-old Asian woman's hair turned from black to gray and then white due to family and marital stress. After she took a vacation, resolving her marital issues, her hair remarkably regained its black color.
Personal Experience: Stress and Hair Graying
The speaker shares a personal experience of rapid hair graying after immigrating to Canada and facing significant work-related stress. By learning to manage stress, she was able to improve the condition of her hair.
Nutritional Deficiencies and Gray Hair
-
Nutrient deficiencies: Lack of nutrients such as copper, iron, and zinc, which are catalysts for melanin production. A deficiency of these microelements will affect tyrosinase activity, then influence melanin production.
-
Protein: Hair is primarily made of protein, particularly tyrosine, a key ingredient for melanin synthesis. Insufficient protein intake can hinder melanin production.
-
B Vitamins: Especially B12, are crucial for melanin production. Foods rich in B vitamins, such as green vegetables and whole grains, should be consumed.
Hair Care Tips
The speaker suggest head massage of the five meridians.
Can Gray Hair Turn Black Again?
While rare, some instances of gray hair reversing to its natural color have been observed, often associated with specific medications.
-
The Journal of the American Medical Association reported cases of lung cancer patients whose hair turned from white to black after taking immunotherapy drugs.
-
An 85-year-old Parkinson's patient experienced hair darkening after taking levodopa.
However, these medications have serious side effects and are not prescribed for hair color changes. There is currently no effective and safe drug that can turn grey hair black.
Scientific Breakthroughs: Reversing Gray Hair in Mice
Recent scientific research has shown potential for reversing gray hair. A 2020 Harvard University study induced gray hair in mice through excessive exercise and disrupted sleep cycles. This was attributed to the over-activation of the sympathetic nervous system, releasing norepinephrine and depleting pigment stem cells.
However, researchers were able to reverse the graying by inhibiting norepinephrine secretion, suggesting that controlling norepinephrine levels could potentially reverse gray hair in humans.
New York University's Research: Pigment Stem Cells Trapped
Recent research from New York University challenges the notion that aging causes pigment stem cell depletion. Instead, the researchers discovered that pigment stem cells in middle-aged and older people are trapped in the hair follicles. As hair ages and sheds, these cells get stuck in an area called the bulge. Unable to return to their original position and produce melanin, the hair turns gray. If these trapped stem cells could be freed and allowed to move again and generate melanin, reversing gray hair may become possible. Research is on-going to further explore this subject.
Acceptance and Alternatives
If one dislikes gray hair, hair dye remains an option. Ultimately, maintaining a positive outlook, balanced nutrition, and healthy habits is the most important factor for overall hair health, regardless of its color.