Every wonder what's up with gray hair? It's absolutely beautiful but not everyone is thrilled with premature gray hair. Is it really caused by stress? Why do some people "go gray" sooner than others? There are genetic factors, but can nutrition also influence its onset? -- Gray hair may be partially caused by a buildup of hydrogen peroxide in the hair follicles. --GPX is a gene that codes for glutathione peroxidase production which normally safely converts hydrogen peroxide t