also, really tight hair styles aren't good either - better to keep the hair back with clips than to pull it hard:
[quote]Wearing tight braids, ponytails or buns causes baldness.
TRUE: Traction alopecia is a very real hair loss condition that is quite common amongst older African American women. It results from wearing tight ponytails, cornrows or buns over an extended period of time. Over time, hair breakage or loss as the result of tight, stressed styles, can become permanent. Avoid this potential problem by opting for looser styles that minimize scalp tension.[/quote]
from:
http://health.learninginfo.org/hair-care/myths.htm
there's some interesting hair myths on there, some that are true, some that are false. some interesting ones: brushing your hair 100 times a day isn't good (so Brady Bunch Marsha and Jan hair brushing was wrong!) and smoking can cause grey hair and hair loss.