Teenagers get gray hair for the same reason as adults. Hair goes gray when color-producing cells stop producing pigment, according to Jeffery Benabio, MD, a dermatologist with Kaiser Permanente. Gray hair is considered premature in Caucasians under 20 years of age and African Americans under 30. There are a few health conditions that can cause premature graying, but these are not typically the cause, according to WebMD.
Health problems that can cause premature graying include vitamin B-12 deficiency, pituitary gland and thyroid gland issues, according to WebMD. Outside of these rare causes, doctors do not know what causes premature graying, though genetics seems to play a role. Typically, Caucasians begin to gray is their mid-30s, Asians in their late 30s, and African Americans in their mid-40s. Teenagers may be highly affected on a psychological basis by premature gray hair, according to Hairfinder. Schoolyard bullying and a feeling of being different may cause severe distress in teenagers with prematurely graying hair. Premature graying may be stopped or helped by avoiding smoking and taking a daily supplement combination of 15 mg zinc and 1 mg copper, which has been shown to delay the arrival of gray hair in young people. Reminex GH, a hair color restoration vitamin, can also provide assistance.