Gray Hairs Can Be Reversed, According To Science

Found a gray hair? You're probably wondering whether to embrace the silvery strands or start the long journey of covering them with dye.

But what if some gray hairs weren't as permanent as we once thought?

In 2021, researchers published a study in eLife documenting cases where some individual gray hairs naturally regained pigment.

Why does hair turn gray?

Hair gets its color from melanin, a pigment produced by specialized cells within the hair follicle.

Over time, these cells become less active and produce less pigment, causing new hairs to grow in shades of gray or white.

Age and genetics remain the biggest factors determining when this happens.

However, researchers have also explored whether factors such as stress and lifestyle may influence how quickly the process unfolds.

While stress isn’t considered the primary cause of gray hair, emerging research suggests it may affect biology within the hair follicle.

How did researchers discover gray hair could reverse?

Your hair is constantly growing, so each strand acts like a timeline. The tip or end is the oldest part of the hair, while the root is the newest.

Researchers analyzed individual hairs to see where color changed along each strand.

Some hairs showed a dark-to-gray transition, while others showed the opposite pattern: gray/white sections followed by darker growth closer to the root.

The researchers documented several examples of these naturally repigmented hairs, describing their work as: “the first quantitative account of the natural and transitory reversibility of hair greying in humans”.¹

The findings don't mean every gray hair can regain its color.

But they do suggest that some gray hairs may still have the ability to regain color, especially in the early stages of going gray.

Could stress influence hair color?

Possibly - but it's unlikely to be the whole story.

(Photo by iStock of a woman looking in the mirror at gray hairs)

Researchers compared changes in hair color with participants' reports of stressful periods in their lives.

In some cases, hairs that had turned gray appeared to regain their pigment during periods when people reported feeling less stressed.

This doesn't prove stress causes or reverses gray hair. Age and genetics are still the biggest drivers of graying.

Instead, the findings suggest stress may influence what's happening inside the hair follicle, making it one of several factors that could affect how quickly some hairs lose their color.

How does gray hair regain its color?

The gray hairs seemed to come from follicles that were under more biological stress.

That suggests hair color may depend not just on age, but also on what’s happening inside the follicle. Scientists are still working out exactly how these processes interact, but the findings suggest losing pigment may not always be completely irreversible.

So, can gray hair be reversed?

The short answer is: sometimes, in some individual hairs.

The study involved just 14 participants and documented isolated hairs regaining pigment rather than widespread reversal across the scalp.

(Photo by iStock of a woman showing her gray roots) 

The researchers focused mainly on young-to-middle-aged participants because earlier evidence suggests repigmentation events may be more likely in the early stages of graying.

Larger studies are needed before scientists can determine how common this phenomenon is or whether it could one day be influenced through targeted interventions.

For now, the research offers an important reminder that some aspects of aging may be more dynamic than previously thought.

Gray hair has long been viewed as one of the clearest signs of getting older, but this research suggests that, under certain biological conditions, even this familiar process may be more complex than we once believed.

Read More: LEDs vs Lasers for Hair Regrowth: What the Science Really Say

References

1. Rosenberg, A. M. et al. Quantitative mapping of human hair greying and reversal in relation to life stress. eLife 10, e67437 (2021).

2. Philpott, M. P. Watching hair turn grey. eLife 10, e70584 (2021).