I am not a nutritionist or a hair dresser, and these are only recommendations. YMMV
Eating well and taking a vitamin supplement may help. Especially make sure you’re getting a good amount of folic acid in your diet. Folic acid (aka Folate) seems to stimulate hair and nail growth. Since your nails grow quickly, I am inclined to think that maybe you may be doing alright there.
Another thing that might help is using a shampoo brush to gently massage yourscalp for a few minutes a day (ie when you are shampooing). This will stimulate the scalp and promote better circulation to get your follicles producing healthier hair.
Do you blow-dry your hair? If you do, then stop. The heat and whipping around caused by a blowdryer can cause the hair to be brittle, increasing breakage. If you absolutely must use a blow dryer, use it on the lowest setting you can for the shortest period of time you can. Personally, my “hairdryer” is a big, thick terrycloth bathrobe that I wear when I get out of the shower. It takes longer for my hair to dry, but it stays healthy longer, too.
That brings up another point: Towel-drying. Don’t vigorously dry your hair with a towl,but gently pat and wring it dry. This is less stressful to the hair strands.
[sub]Bet you never though you would be taking beauty tips from a heterosexual man, huh?[/sub]