What is the cause and remedy for premature hair graying ? At present my age is 21 but still my hair? have been turn gray/white.

Causes of Premature hair graying can be genetic,environmental ,or health-related .Vitamin deficiencies like vitamin b12 , folate, iron, copper and vitamin d can contribute to premature graying. Hormonal imbalances can also contribute. stress and smoking are also responsible. While there is no permanent cure for premature graying, several treatments may help manage or slow the process like hair dyes, vitamin b12 and folate supplements, biotin and collagen supplements. There are treatment options available so consult a dermatologist or a trichologist for an accurate diagnosis and treatment