Grey hair can be a nightmare, especially for women. This is a universal and widespread problem that occurs when melanocytes around the hair follicle reduces the amount of melanin it produces (or stops completely). The hair is mainly made from a protein called keratin, and as the hair grows, the melanocytes around the hair follicle inject melanin into the cortex of the hair shaft, which results in its dark color. Keratin without melanin is a yellowish grey color, so when the melanocytes slow down, the hair begins to lose its color.
There are several causes for this decrease in melanin production. Some are natural—such as genetics, age, and natural chemical changes in the body. Other causes are due to extrinsic factors that may be treatable, such as diet and stress. Many chemical hair colors contain ammonia, which is an industrial bleaching agent and severely harms the hair in the long run. Always avoid chemical based shampoos and use herbal ones instead. Other extrinsic causes can be more difficult to avoid, like pollution.