New Study Finds Some Grey Hair Can Naturally Become Coloured Again

The results of a recent study confirm something I've known for a while: a gray hair can revert back to its natural colour as it grows.

To be clear, once a hair is grey it stays grey but, as it grows, the colour can come back in the new growth. As someone who started going grey at age 13, I've now got a full head of mostly grey/white/silver hair that I love and find very interesting. You see, I've found multiple long strands of hair that are grey for several centimeters from the tip, dark brown for a bit in the middle, then grey again to the root.  A new study finds that this is not unique to me.

The study "Quantitative mapping of human hair greying and reversal in relation to life stress" has been published in the journal eLife.  Researchers took hair samples from 14 people, 7 male and 7 female, who said they had some grey or bi-colored hair and hadn't coloured or bleached their hair.  They collected dark, white, and bi-color hairs from these healthy participants and analyzed the hair by digitizing and then measuring the changes in colour in single hairs.

Stress and Grey Hair

You may have heard that stress can turn hair grey or white, especially traumatic stress. Cartoon and movies sometimes have a character's head of hair turn white after a traumatic event. That's doesn't happen in real life. Once your hair has colour, it doesn't just lose colour. But, there have been documented cases where people suddenly 'go grey', that is, all their hair starts growing out without colour. This is known as "Marie Antoinette Syndrome" due to the stories of her hair going grey just before she was beheaded. You can read more on that HERE.

Recent science does suggest that stress can turn your hair grey or white. What this study found, though, is that, once the stress is gone, hair can continue growing in colour ("repigmentation"). This is the first time that this has been scientifically documented. The researchers in this small study looked at where participant's hair started to lose colour and then reversed. They asked those two participants to go back through their life and mark any points of stress. Researchers found "Aligning the hair pigmentation patterns with recent reports of stress in the hair donors’ lives showed striking associations. When the donor reported an increase in stress, a hair lost its pigment. When the donor reported a reduction in stress, the same hair regained its pigment."

Anti Aging?

What does this mean for you and your grey hair? The researchers put together a mathematical model and "[t]he model suggested that there might be a threshold for temporary greying; if hairs are about to go grey anyway, a stressful event might trigger that change earlier. And when the stressful event ends, if a hair is just above the threshold, then it could revert back to dark." So, reducing stress in your life might stop hair from turning grey prematurely and it might even reverse some of the grey you already have. Down the road, this study may inform better stress management tools and may even give scientists a better understanding about the process of aging and how it might be slowed.

Researchers also posit the following,

"In the future, monitoring hair pigmentation patterns could provide a way to trace the effectiveness of treatments aimed at reducing stress or slowing the aging process. Understanding how ‘old’ white hairs regain their ‘young’ pigmented state could also reveal new information about the malleability of human aging more generally." (emphasis added)