First and foremost, most of us would KILL to look like James Dean, so if you can pull that off, I think you're fine. That said, the main thing that caught my attention in your post was malnutrition. From my personal research, I found that at the very least, malnutrition can leave you with flat, thin hair. I don't know that any studies have been done on this (what doctor would starve people to see if they lose hair) but stressing your body and depriving it of nutrients is bound to hurt you. Please take time to ensure that you're getting proper food, including your fruits and vegetables - vitamin B complex helps with healing and strong hair - and that will have you on the right track