Stress May Create Gray Hair, but Calm May Reverse It

As melanin, a pigment present in the skin, eyes, and hair, diminishes, hair color fades and creates gray hair.

Before hairs emerge from the scalp, they develop beneath the skin in follicles that are stimulated by chemical and electrical signals from the body, including stress hormones. Once hairs develop, they stiffen and retain their molecular structure, which is reflected in their color.

Scientists can now identify minute color changes in single strands of human hair using high-resolution scanners.

The researchers assessed color loss in single strands of human hair from 14 participants who kept weekly stress diaries. The findings were startling: As the participants’ stress levels increased, their hair began to lose color. However, when the tension subsided, their hair returned to its natural hue, according to Martin Picard, Ph.D., an associate professor of behavioral medicine at Columbia University’s Vagelos College of Physicians and Surgeons in New York City.

The researchers developed a technique for capturing pictures of hairpieces that are so little that they reflect an hour’s growth. Ayelet Rosenberg, a research assistant in Picard’s laboratory and the study’s first author, devised the approach that enabled the researchers to quantify pigment loss.

Additionally, as hair color changed, the scientists saw changes in 300 proteins.

They built a mathematical model to anticipate what may happen to human hair over time and propose that there is a period in a person’s life when stress might temporarily cause color loss, which can be reversed when tensions subside.

These results contribute to a growing body of research demonstrating that aging is not a linear, irreversible biological process; it may be slowed down or even reversed momentarily.

With greater knowledge of the biological basis of pigment loss, gray hair may one day be reversible with a visit to the doctor’s office rather than the hair salon.