Evidence shows that age and stress are two factors that contribute to the development of gray hair.
A new study suggests that melanocyte stem cells (McSC) tend to get “stuck” with age, leading to graying hair. Researchers posit that McSC cells may be the key to preventive treatments.
You can empower some patients to lower their odds of going (and staying) gray by reducing stress and eating a diet high in vitamin B12, iron, and copper.
It’s rumored that on the evening prior to her execution in 1791, Marie Antoinette’s hair turned gray. Although the appearance of sudden gray hair is now known by researchers as canities subita—and thought to be an extreme form of alopecia areata—this legend touches on one of the more common causes of gray hair: stress, according to experts at Columbia University Irving Medical Center.
Another factor that contributes to gray hair, to which no human is impervious, is age.
New research sheds light on the stem cells that play a major role in the development of gray hair as the body ages—as well as how these cells could pave the way for future preventive treatments.
Why hair turns gray
Gray hair affects everyone who reaches a certain age.
According to an article published by Annals of Dermatology, there are three widely known theories that explain why hair goes gray:
Melanocytes, which produce melanin in the hair matrix by the hair follicle’s dermal papilla, either fail to function or become depleted.
Genotoxic stress leads to defective melanocyte stem cell (McSC) system self-maintenance in the hair bulge.
Active hair growth may lead to genotoxic or oxidative stress in the hair bulge.
To better understand the failure of the McSC system, researchers used live imaging and single-cell RNA sequencing on mice in a 2023 study published by Nature.
These processes revealed that McSCs are capable of translocation, traveling between hair follicle stem cell and transit-amplifying compartments in the hair.
Subject to local microenvironmental cues, McSCs then “reversibly enter distinct differentiation states,” the authors wrote. This function ultimately allows for McSCs to pick up on maturity-influencing protein signals that determine whether they’ll create protein pigments.
As the lifecycle of hair continues throughout a person’s life, however, researchers found that McSCs become stagnant in the stem cell compartment, known as the hair follicle bulge. Once stuck, they cannot evolve into their usual trans-amplifying state, which prevents them from returning to their origin in the germ compartment. This is the point at which McSCs stop producing pigment, and thus give way to the gray.
Study senior investigator Mayumi Ito, PhD, and professor in the Ronald O. Perelman Department of Dermatology and Department of Cell Biology at NYU Langone Health remarked on the clinical significance of the study in an article published by NYU Langone Health.
“It is the loss of chameleon-like function in melanocyte stem cells that may be responsible for graying and loss of hair color,” said Dr. Ito.
"These findings suggest that melanocyte stem cell motility and reversible differentiation are key to keeping hair healthy and colored."
— Mayumi Ito, PhD, professor with the departments of dermatology and cell biology, NYU Langone Health
Current and future preventive treatments
For those who aren’t particularly excited by the idea of going gray, the Nature study offers hope.
According to study lead investigator Qi Sun, PhD, a postdoctoral fellow at NYU Langone Health, the findings of this study may pave the way for potential preventive treatments.
“The newfound mechanisms raise the possibility that the same fixed positioning of melanocyte stem cells may exist in humans,” Dr. Sun told NYU Langone Health. “If so, it presents a potential pathway for reversing or preventing the graying of human hair by helping jammed cells to move again between developing hair follicle compartments.”
As researchers pursue these potential treatments, you may remind patients to keep stress at a minimum in order to better protect the pigment in their hair, according to the Columbia University experts.
Patients may reduce their stress levels by engaging in social activities, such as volunteering, reaching out to community or family, and getting outside to see some greenery.
Patients may also lower stress levels by practicing gratitude. They can do this by writing down a few things they’re grateful for each day.
Lastly, patients may go the extra mile to take care of their physical bodies by exercising, getting vaccinated, and eating healthy in order to stress less.
A healthy diet is especially important to ward off premature graying, as nutritional deficiencies have been linked to hair hypopigmentation.
In particular, a healthy diet should include sufficient amounts of vitamin B12, iron, and copper.
Overall, progress is being made toward preventive treatments for gray hair. And if you are young and relatively healthy, hair color can be restored in some individuals as stress diminishes, as noted by the Columbia University experts. You can advise your patients to de-stress through self-care, meditation, exercise, and the adoption of other healthy lifestyle activities.
What this means for you
Now that research has revealed the role that the McSC system plays in the development of gray hair, scientists may uncover potential preventive treatments that involve moving or restoring the motility of the McSCs. In the meantime, you may advise some patients who are starting to go gray to engage in stress-reducing activities. Experts say that as stress diminishes, it’s possible that hair color can even be restored in some patients.