Vitamin B12 Deficiency and Hair Loss

Dear Dr Rassman, I am a 22 year old male a few months ago I noticed I was receding around the temple. To be sure I went to see my GP and he agreed there was some thinning particularly around the sides. To be safe he sent me for a couple of blood tests and found out that I have a vitamin B12 deficiency. I started a program of vitamin replacement therapy about a month ago. As I understand things vitamin B12 deficiency can sometimes cause hair loss, but it could also be a coincidental in my case. My question is generally how long does it take before I would notice any regrowth as a result of my treatment? I am asking mostly because I am considering using Regaine if hair regrowth does not occur.

I would want to perform a mapping of your scalp hair to determine if you have male patterned balding. The question is reasonable, but treating the B12 problem is the right thing to do. If you don’t have male pattern baldness, then maybe the B12 will reverse your hair loss in a year or so.