According to WebMD, hair turns grey when color-producing cells stop producing pigment, says Jeffrey Benabio, MD, a dermatologist at Kaiser Permanente in San Diego. Naturally occurring hydrogen peroxide can also build up in the hair, bleaching the color.

Typically, white people start going grey in their mid-30s, Asians in their late 30s, and African-Americans in their mid-40s. Half of all people have a significant amount of grey hair by the time they turn 50.

A white person is considered to be prematurely grey if his or her hair turns grey by age 20; grey before 30 is early for African-Americans.

According to an article on medium comparing Asians and Africans: “74% of people between the ages of 45 and 65 have grey hair, with an average intensity of 27%. Within this age group, men have more grey hairs than women. The age at which hair begins to turn grey and the increase in grey hair with age appear to be clearly linked to ethnic and geographical origin. At a similar age, subjects of Asian or African descent, who have the darkest hair, have fewer grey hairs than those of Caucasian origin, who have lighter hair tones. While men have on average significantly more grey hairs than women of the same age, their hair begins to go grey at the temples, whereas women’s grey hairs are more spread out.”

However it has become increasingly common for Asians in their 30s to experience what is now commonly termed as premature white or grey hair.

It is normal for hair colour 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. An article from Medical News Today shares that the human body has millions of hair follicles or small sacs lining the skin. The follicles generate hair and colour or pigment cells that contain melanin. Over time, hair follicles lose pigment cells, resulting in white hair colour. There can be many causes besides age that result in a person’s hair turning white.  

• Any deficiencies of vitamin B-6, B-12, biotin, vitamin D, or vitamin E can contribute to premature greying.
• Premature greying of a person’s hair is largely connected to genetics, according to a 2013 report in the Indian Journal of Dermatology, Venereology and Leprology.

There is no known health hazards associated  with having white or grey hair. You could also be in the position where you have a perfectly healthy scalp but also tons of white hair. The texture of the white hair is, however, different from that of your normal hair. This is because Melanin supplies the hair with moisture, thus, without Melanin, the white hair seems to have less “bounce” and looks “dead”.

However, some people who have premature white hair find it bothersome from the appearance point of view. To these people it can be stressful and disturbing for some and could even affect their self-confidence, especially for younger men and women.