Stress: Can it really turn your hair gray?
We have all probably noticed it or heard someone mention that American presidents go into office looking reasonably young, complete with dark hair, and come out looking reasonably old, considering how little time had passed. American presidents almost turn gray before our eyes. If you are doubtful, go to Google images and type in Obama. What you will get is a very large assortment of images that chronicle his graying hair.The same is true for Bush.
Where does hair get its color to start with?
It may seem strange but hair gets its color from the same thing that gives your skin its color. Hair gets its color from melanocytes that produce the pigment melanin. Each hair follicle is really just an extension of the epidermis (top layer of skin) down into the deeper layers (dermis). Each hair actually grows inside a little tube of your skin and the melanocytes add pigment to the hair as it grows. While melanocytes are distributed widely throughout your skin, they have a much higher density in the lower parts of hair follicles. (Image of the skin and hair follicle.)
What goes wrong?
In a recent study published in the journal Nature Medicine, Dr Mayumi Ito, the study’s author, reported finding that under high stress conditions, melanocytes migrated away from the area where hair gets most of its color and for some reason the melanocytes don’t come back. Most of the color is added to the hair deep in the follicle in an area called the bulb. The bulb is normally rich in melanocytes so the normal hair is full of pigment. The growth cycle for a scalp hair is 2 – 5 years. The color is added slowly and distributes throughout the cortex (outside) of the hair. After 2-5 years the hair falls out, there is a brief rest period for the hair follicle, which is still alive and well, and then a new hair starts to grow.
Stem cell migration has been observed before. It happens when a hair follicle is damaged (e.g. when you pull (pluck)a hair out). Stem cells then migrate to the damaged area and assist in the repair process. When the repair is complete, the stem cells move back to the bulb and resume their normal functions. However, under the influence of cortisol, the stress hormone, the melanocytes migrate away and don’t come back. As a result, the hair now grows with fewer melanocytes surrounding it and less pigment contributes to its color. Thus the new hair comes out a little less dark than its predecessors. The greater the stress and the longer the duration of the stress, the grayer and grayer the hairs become. As more and more gray or even white hairs are mixed in amongst your normal colored hair, you hair appears to lighten and then turn gray.
Will reducing stress keep me from getting gray hair?
Gray hair has long been associated with age and aging. As you age the number of melanocytes in hair follicles, and your skin for that matter, goes down and their production of melanin diminishes. However, this will vary from person to person. Dr. Ito’s study suggests that stress may speed up the process. If this is the case, then reducing stress, which is a good idea no matter the reason, should reduce the rate of the graying process and push it into the later years where it belongs.