Do you fit into any. Of these categories? Graying of hair is related to genetic predisposition. Age of initial graying is largely a matter of genetics. However stressors: nutritional deficiencies, chemotherapy, traumatic head injuries, low vitamin b levels, zinc deficiency, severe illness, surgery ; marked emotional stress may impact earlier depigmentation in people who are already predisposed to gray hair. Aging is.
You can't. Becoming white or grey haired is largely genetic. If your parents were gray at a young age, you will also likely be gray at a young age. Accept your genetic predisposition or artificially color it.