Premature graying

I am male 24 years old. my weight is 83 kg  and height is 181 cm.
my hair allmost 50% gray now. i am a vegitarian.

i want to know any vitamin defficiancy will cause or not  for premature graying..how can i solve this problem...

if i am going to use B12 vitamin ..it will make any changes?

[Paxiled]

Have no idea, did other members of your family go gray young?  Some just do.  Some go bald young.  Are you feeling any fatigue?  Some people aren't meant to be vegetarians, some are.  You might not be one of them.  B12 is one of the nutrients that is hard to get for vegetarians; the other is L-Methionine, and amino acid.  It won't hurt you to try supplementing with it, or add fish to your diet and see if it makes a difference.  If you buy a supplement, make sure it's the methylcobalamin form.