Gray hair may be a sign of protection against cancer: what scientists have discovered.

According to ТСН: Gray hair may indicate that the body is effectively defending itself against cancer. This conclusion was made by researchers who studied the reaction of stem cells to DNA damage.

The results of the study were published in the journal Nature Cell Biology.

Choosing between graying and getting sick

The color of hair is determined by melanocytes — cells that produce pigment. These cells are constantly renewed thanks to stem cells located in hair follicles.

During aging or under the influence of harmful factors (such as ultraviolet light or radiation), the DNA of melanocytes gets damaged. Researchers at the University of Tokyo found that at this moment the body activates a protective mechanism.

Damaged stem cells stop dividing and 'turn off.' This process is known as cellular aging.

• Result: The reserve of pigment cells is depleted, which causes the hair to start turning gray.

• Goal: By stopping division, the cells prevent the transmission of damaged DNA and do not turn into cancer tumors.

Thus, graying is a certain price for protection. The body 'sacrifices' hair color to avoid uncontrolled reproduction of mutated cells.

Experiment on mice

Researchers tested this theory on mice by exposing them to radiation and chemical compounds.

1. Radiation: Stem cells reacted to DNA damage by stopping division. The fur of the animals grayed, but tumors did not appear.

2. Chemical carcinogens: Some substances 'deceived' this protection, allowing damaged cells to continue dividing. As a result, the fur color remained, but the animals later developed cancer.

A new perspective on aging

Professor Emi Nisimura, the lead author of the study, believes that this discovery fundamentally changes the perception of graying.

“This recontextualizes graying hair and melanoma (skin cancer) not as unrelated events, but as different consequences of stem cells' reaction to stress,”

— she explained.

So now graying can be seen as an effective 'anti-cancer safeguard.' The next step for scientists will be to research how this mechanism works in human hair follicles.

Recently, doctors reported the complete recovery of patients with multiple myeloma — a severe type of blood cancer. Revolutionary immune therapy ensured remission in most study participants, and some of them completely lost disease symptoms.