Can gray hairs repigment?

The essential point to remember.

The appearance of gray hair is primarily due to a decrease in melanin production by the melanocytes and their gradual decline, although stress and certain genetic and pathological factors may also be involved.
White hair resulting from aging or chronic disease cannot naturally regain its original pigmentation.
In rare stress-related cases, some hairs can naturally repigment, as recent studies have shown.
If you wish to regain colored hair, the most effective solution to date remains the use of hair coloring.

4 minutes to understand your skin. Our dermatological diagnostic guides you toward the ideal skincare for your specific needs. Simple, quick, personalized.

Why does hair turn white?

The emergence of white hair, a process called canities, results from a progressive decline in melanin production by melanocytes, the cells responsible for pigmentation. With age, their number and activity naturally decrease, which explains why hair typically begins to turn white around age 35, sometimes later depending on the individual. However, certain internal or external factors can accelerate this process and lead to a premature canities.

The stress is among the most studied causes: it can disrupt the balance of the hair follicle by altering melanocyte function, leading to pigment loss. Nutritional deficiencies can also play a role. A lack of vitamins B9, B12, or D, as well as minerals like selenium, iron, or copper, can impair hair health. Copper, for example, is essential for tyrosinase activity, a key enzyme in the conversion of tyrosine to melanin. Finally, the genetics and individual susceptibilities remain determining factors: some people inherit a predisposition to develop white hair early in life, while certain autoimmune diseases such as the vitiligo can also be involved in the premature onset of white hair.

Le processus d'apparition des cheveux blancs. — The process leading to the formation of white hair.
Source: PHILPOTT M. Watching hair turn grey. eLife (2021).

Can white hair naturally recolor itself?

Many individuals with silver hair would like to naturally restore their original pigmentation. But is that feasible? Yes and no.

In fact, it depends on the cause of canities. If your white hair is due to aging, and thus to decreased melanocyte activity, this is an irreversible phenomenon and your hair will not be able to naturally return to its original color. Likewise, if the cause is a chronic disease, canities cannot be reversed. However, if stress is responsible for your white hair, some scientific evidence suggests that it is possible that they may naturally regain their color.

Indeed, a recent study documented this natural repigmentation in 14 participants, with a mean age of 35 years. The researchers observed white hairs reverting to pigmented in multiple body areas, including the scalp, beard, and even pubic hair. Although this phenomenon is rare and limited to a few isolated hair follicles. It demonstrates that the reversibility of canities is not strictly theoretical. Some hairs exhibited complex transitions, switching from white to pigmented and back to white again within a single hair growth phase (anagen), underscoring the dynamic and transient nature of these pigmentary changes.

The mechanism underlying this repigmentation depends on melanocytes and their precursor cells. Researchers suggest that the recoloring could be triggered by the activation and differentiation of a subpopulation of immature melanocytes located in the outer root sheath of the hair follicle, or more likely by migrating transient melanoblasts. These cells would be capable of regenerating hair pigmentation by replacing depigmented melanocytes. Thus, repigmentation could occur over a brief period, sometimes in as little as a few days, and reach complete pigmentation in a median time of about three months.

The study also quantified the rate of pigmentary changes. White hair fading proceeds at a variable pace, from 0.2% to 14.4% pigment loss per day, while natural repigmentation can occur at a similar or slightly faster rate—on average up to 30% quicker. These observations demonstrate that recoloring is not a gradual reversal but a rapid, discrete, and intermittently reversible phenomenon that can unfold within the same timeframe as the initial whitening.

Finally, researchers have explored the role of psychological stress in this process. Previous studies have shown that chronic stress and exposure to certain biological signals can accelerate hair depigmentation by exhausting melanocyte stem cells. These findings are consistent with empirical observations in which periods of intense stress appear correlated with the emergence of white hair, while stress reduction may favor natural repigmentation.

Hair graying may not be inherently irreversible: part of its dynamics could be modulated by psychological or environmental factors, although such repigmentation remains rare and limited to certain follicles.

How can you restore your original hair color?

White hair is a physiological phenomenon that does not necessarily need to be concealed. However, some individuals prefer to maintain their original color, which is perfectly valid. If your hair has grayed or whitened, you can restore its natural hue through hair dyes. We recommend consulting a professional stylist for this procedure rather than attempting a home coloring, unless you are certain of your technique. In fact, it is common for stylists to see clients who have tried self-dyeing and achieved less than satisfactory results.

We can also mention certain topical products enriched with peptides and/or plant extracts that claim to repigment white hair. However, the results reported by individuals who have tried them are inconsistent. Some say they have indeed observed a repigmentation of their white hair, while others have seen no change.

Note : The scientific literature reports a few isolated cases of individuals receiving immunomodulatory treatments or monoclonal antibody therapies who observed repigmentation of their gray hair. However, these are very rare events and should in no way encourage the use of such medications by individuals without an underlying medical condition and without medical advice.