Fact Or Fiction - Stress Causes Gray Hair?

There is no fixed defined age for graying in human beings. The first silvery strands usually become visible around the age of 30 for men and age 35 for women. However, in some people graying can show up as early as high school and for some as late as in the age bracket of 50s. However, one thing is certain. Premature graying is on the rise.

The human head has about 100,000 of teardrop-shaped cavities called follicles, each capable of sprouting several hair in a lifetime. The pigment in the hair shaft is generated from cells at the base of the root of the hair. Keratinocytes build the hair from the bottom upwards, stacking atop one another. These eventually dye leaving behind mostly keratin, a colorless protein that gives hair its texture and strength. While the keratinocytes construct hair, the neighboring melanocytes manufacture a pigment called melanin. This pigment is delivered to the keratinocytes via melanosomes. There are two shades of hair melanin; eumelanin, which is dark brown or black in color and pheomelanin, yellow or red in color. These two combine in different proportions to create a vast array of human hair colors. At any given time, around 80 to 90 percent of the hair of an individual are in an active growth phase. This growth may last for two to seven years. At the end of this stage, the follicle shrivels, the keratinocytes and melanocytes undergo programmed cell death and the follicle enters a resting phase. This resting phase is marked by hair fall.

The scientists at Harvard proposed that a failure of melanocyte stem cells (MSC) to maintain the production of melanocytes could cause the graying of hair. As we get older, melanocytes start producing less pigment. Gradually, there arises a stage when there is no pigment at all in the hair. This gives the hair a transparent shade. Hair that has lost most of its melanin is gray, whereas hair that has lost all of this pigment is white.

The main cause of premature graying involves heredity factors. If the parents have grayed early, there is a possibility of the same characteristic being transferred to the child through the genes. Although scientists would not like to believe, stress may be playing a role in a more gradual graying process. People today are living an extremely mechanical life. There is constant stress to meet the deadlines at office and complete household chores. This rushed life style causes excessive stress and strain that disrupts the entire body system.

Although no clear correlation has been identified between stress and gray hair, research exemplifies that stress hormones may have an impact on the activity or existence of melanocytes. Stress hormones produced either systemically or locally by cells in the follicle could produce inflammation that drives the production of free radicals. These free radicals could influence melanin production or induce bleaching of melanin. There is further evidence that local expression of stress hormones mediate the signals instructing melanocytes to deliver melanin to keratinocytes. Therefore, a disruption in that signal results in melanin not delivering pigment to the hair.

Stress, long working hours, nutrient deficient diet and excessive caffeine are common features in the life of today's youth. These very factors could also be contributing towards the premature graying of hair. No wonder the modern generation is aging faster than the earlier generations!