It is normal for hair color to change, as people age. But white hair can appear at almost any time in life. Even teenagers and people in their 20s may notice strands of white hair.

The human body has millions of hair follicles or small sacs lining the skin. The follicles generate hair and color or pigment cells that contain melanin. Over time, hair follicles lose pigment cells, resulting in white hair color.

In this article, we look at some common causes of prematurely white hair, along with ways to slow the graying process down or prevent it, in some instances.

Fast facts about white hair:

 

  • Vitamin deficiencies can cause hair to turn white prematurely.
  • Smoking has long been linked to premature graying.
  • Preventing white hair depends on its cause

Causes of Grey Hair

There can be many causes besides age that result in a person’s hair turning white.

Vitamin deficiencies

Grey Hair

 

Genetics

Premature graying of a person’s hair is largely connected to genetics, according to a 2013 report in the Indian Journal of Dermatology, Venereology and Leprology.

Race and ethnicity play roles, as well. Premature graying in white people can start as early as 20 years old, while a person can be as young as 25 years old among Asians, and 30 years in African-Americans populations, according to the same 2013 study.

Oxidative stress

While graying is mostly genetic, oxidative stress in the body may play a part when the process happens prematurely.

Oxidative stress causes imbalances when antioxidants are not enough to counteract the damaging effects of free radicals. Free radicals are unstable molecules that damage cells, contributing to aging and disease.

Too much oxidative stress can promote the development of diseases, including the skin-pigment condition vitiligo. Vitiligo may also turn the hair white due to melanin cell death or the loss of cell function.

Certain medical conditions

Some medical conditions, including autoimmune diseases, may increase a person’s risk for graying early. In fact, research published in 2008 showed a connection between hair abnormalities and thyroid dysfunction.

White hair is also common in alopecia areata, an autoimmune skin condition that causes hair loss on the scalp, face and other parts of the body. When the hair grows back, it tends to be white due to melanin deficiency

Smoking

A study from 2013 reported in the Italian Dermatology Online Journal, shows that smokers are 2 1/2 times more likely to start graying before age 30 as non-smokers.

A 2015 study in the Journal of the American Academy of Dermatology also demonstrated that smoking is linked to premature white hair in young men

Chemical hair dyes and hair products

Chemical hair dyes and hair products, even shampoos, can contribute to premature hair graying. Many of these products contain harmful ingredients that decrease melanin.

Hydrogen peroxide, which is in many hair dyes, is one such harmful chemical. Excessive use of products that bleach hair will also eventually cause it to turn white.