From time to time again there has been sayings that age, too much hydrogen peroxide inside the body and stress can cause people hair to go gray but most of this is contradicting because some people that are younger than others have more gray hairs and some younger people that are more stressed out than older people don't have none to very little gray hairs than some older people that are less stressed out. It also has been said that Scientists don’t know exactly why some people go gray at an younger age. In my opinion no matter how you look at it there has to be one main cause that causes the chain reaction that causes the spreading out of gray hairs throughout the human body and in my opinion the main cause of this is an small insect and what insect it is Scientists are just going have to figure that one out.