Hair problems.. could this be caused by my diet?

I'm 17, and I've been vegetarian for about a year and a half, and vegan for a little over a year. Recently I've been having a lot of breakage in my hair; I have lots of split ends, and in bright light it looks like it's splitting almost all the way up my hair. I don't use a blow dryer, and I very rarely use a curling iron or straightener. I never seemed to have this problem until just a few months ago. Do you think it could possibly be caused by my diet? I eat a good amount of protein, probably at least fifty grams a day.