After 30 years, each additional decade brings a 10 to 20% chance of seeing your hair gray. It’s a proven fact, systematically everyone sooner or later sees their hair turn gray. Hair color comes from a pigment, melanin. Each hair can contain dark melanin (eumelanin) and light melanin (pheomelanin), which mix together for the former the many color shades of human hair.
When we are young, special pigmented stem cells, the melanocytes, inject pigments into cells containing keratin. This keratin, which is a protein, constitutes the hair and gives it its color. As you age, melanin becomes scarce, which is why hair turns gray and then white (meaning there is no melanin left at all).
A gene responsible for gray hair
What causes the decrease in melanin and the graying of hair has long remained a mystery. An international team of researchers has discovered the first gene responsible for gray hair.
The study involved a genome-wide association analysis in more than 6,000 Latin Americans, to search for genes responsible for different characteristics of hair and facial hair, including graying hair and hair, baldness, beard thickness, mono eyebrows, eyebrow thickness, etc.
A gene that was first identified as being responsible for blond hair in Europeans was also found to be responsible for gray hair and was responsible for around 30% of the study participants’ graying hair. The remaining 70% is certainly due to factors such as age, environment, stress, etc.
For some people the process is rapid, while for others it takes place slowly, over decades. It is known, for example, that people with white skin begin to gray around the age of 35, while Asians generally begin to gray in their late thirties. African-Americans generally do not turn gray until they are 45 years old.
Why else does our hair turn gray?
Here are some other factors that cause hair to turn gray:
– Hydrogen peroxide: Hydrogen peroxide is a well-known product for bleaching hair, but few people know that hair cells also produce it. As you age, the amount produced increases, and researchers believe this eventually discolors hair pigments, turning hair gray and then white.
– Smoking: There is a significant relationship between smoking and graying hair. Smoking is also responsible for premature graying of hair, causing the first gray hairs to appear before the age of 30.
– Oxidative stress: Oxidative stress can be defined as a state in which your free radicals (from pollution, poor diet, stress, etc.) outnumber your antioxidants (obtained through a healthy diet) . Hair that turns gray can be the result of oxidative stress. Research has also shown that people with premature gray hair have higher levels of pro-oxidants and lower levels of antioxidants than those without.
– Vitamin B12 deficiency: This is also a factor in premature graying of hair, and there is at least one reported case of return of hair pigmentation after such a deficiency has been corrected.
Is premature graying of the hair a sign of health problems?
The cause of premature graying is largely genetic. If some of your family members had early gray hair, chances are you did too.
Obesity, too, is associated with premature graying, and it is suspected that it could be a telltale sign of other health problems. Premature graying of the hair would, for example, be an important risk marker for osteopenia, which is a bone condition. According to a study published in the Journal of Accelerated and Clinical Endocrinology, people with early graying but no other identifiable risk factors were 4.4 times more likely to have osteopenia than people without graying. premature.
Links have also been made between premature graying and thyroid disorders, anemia and vitiligo, and even with an increased risk of coronary artery disease in young smokers. Early graying of the hair can be considered by doctors as a first clue to identify a patient at risk for premature MAC, especially in smokers.
Does stress promote gray hair?
It’s commonly believed that stress causes gray hair to appear (many parents of teenagers, or former presidents whose hair often turns gray while in office, could attest to this.) had yet never found an explanation for this phenomenon, until a 2011 study published in the journal Nature, conducted by Nobel Prize winner Dr. Robert Lefkowitz. This study established that chronic stress and frequent activation of the stress response causes DNA damage that can not only promote aging, cancer, neuropsychiatric conditions, but it also affects genes controlling hair pigments. .
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