•Grey hair
Grey hair may be more than a sign of ageing. A new study suggests it could indicate that the body is defending itself against melanoma, the deadliest form of skin cancer.
As reported by Women’s Health yesterday, researchers found that when the pigment-making cells in hair follicles—melanocyte stem cells—are damaged, they exit the body instead of dividing.
If they kept dividing, they could contribute to tumour formation.
“While grey hair develops, the risk of melanoma simultaneously decreases,” said Yasuaki Mohri, lead study author and assistant professor at The University of Tokyo.
The study, published in October 2025 in Nature Cell Biology, examined melanocyte stem cells in rodents exposed to cancer-causing substances.
The cells either left the system, producing grey hair, or continued dividing, which could lead to tumours.
Mohri explained that this process “functions as a protective mechanism against melanoma,” removing potentially cancerous cells from the hair follicle.
Experts, however, cautioned that grey hair doesn’t guarantee safety from skin cancer.
Dermatologist and director of Eternal Dermatology + Aesthetics, Ife J. Rodney, said, “When these cells are gone, you get grey hair, but other factors still influence melanoma risk.”
Assistant clinical professor at Mount Sinai, Gary Goldenberg, added, “Having grey hair doesn’t mean you’re immune. Many patients with silver strands still develop melanoma.”
Risk factors include sunburn, chronic sun exposure, light skin, family history, and tanning bed use.
Doctors emphasised sun protection. Rodney said, “Strict sun protection is key,” and added that more human research is needed.
“Grey hair shouldn’t be used to predict your melanoma risk or change your behaviour. Sunscreen is still essential,” he said.
