is a question I was asked during Anatomy & Physiology lecture the other day. As new hairs form and grow, pigment producing cells called melanocytes inject them with color known as melanin, turning them blond, red, etc. Melanin production slows as we age. If it eventually comes to a complete halt, our hair turns gray. So your gray hair just lacks pigment. Researchers say the contrast of the noncolored hair against the rest gives it a clear, grayish cast. So where is this cast coming from on an entirely gray head?
Research indicates that most will get gray hair but it differs in how much. Research indicates that graying is not solely dependent on genes although genetics plays a role. About 32% of women are under 30 when they find their first gray strand. Gray hair is described as stiffer and drier which makes it difficult to mask. Interesting thoughts-
Resource: realsimple.com November 2011