The article discusses the factors contributing to the development of grey hair, particularly focusing on the role of melanocyte stem cells (McSCs) and how age and stress affect them. It also mentions potential preventive treatments and lifestyle strategies to manage greying hair.

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The appearance of sudden grey 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 grey hair: stress, according to experts at Columbia University Irving Medical Center.

Another factor that contributes to grey hair, to which no human is impervious, is age.

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Why hair turns grey

Grey 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 grey:

1. Melanocytes, which produce melanin in the hair matrix by the hair follicle’s dermal papilla, either fail to function or become depleted.
2. Genotoxic stress leads to defective melanocyte stem cell (McSC) system self-maintenance in the hair bulge.
3. 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 experimental models in a 2023 study published by Nature.

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 grey.

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 greying and loss of hair colour,” said Dr. Ito.

“These findings suggest that melanocyte stem cell motility and reversible differentiation are key to keeping hair healthy and coloured.”

- Mayumi Ito, PhD, professor with the departments of dermatology and cell biology, NYU Langone Health

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Current and future preventive treatments

For those who aren’t particularly excited by the idea of going grey, 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 greying 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 Columbia University experts.

Patients may also lower stress levels by practising 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.

In particular, a healthy diet should include sufficient amounts of vitamin B12, iron, and copper.

Overall, progress is being made toward preventive treatments for grey hair. And if you are young and relatively healthy, hair colour can be restored in some individuals as stress diminishes, as noted by Columbia University experts. You can advise your patients to de-stress through self-care, meditation, exercise, and the adoption of other healthy lifestyle activities.

Disclaimer: This story is contributed by Jules Murtha and is a part of our Global Content Initiative, where we feature selected stories from our Global network which we believe would be most useful and informative to our doctor members.