Top Reasons for White Hair Setu Nutrition Can You Reverse Gray Hair? Understanding the Role of Vitamins Can White Hair Turn Black Again Naturally Dr. Sandeep Bhasin Care Well Medical Centre 1 in 3 people under 30 have premature greying , Most of them are B12 deficient , Your hair didnt age your mitochondria did., #B12Deficiency Grey hair isnt age, its a signal., Your cells are According to research, an excessive buildup of hydrogen peroxide is a primary cause of grey hair. This buildup bleaches the hair from the inside out and damages the melanocyte melanin producing cells Why does hair turn gray? Harvard Health