Why do people with cancer shave there head?
Chemotherapy, used to treat cancer, causes the hair to fall out. Some people may shave their head if their hair didn't all come out, because they'd rather be completely bald than just have some spots that have hair.
People shave their hair off for different reasons. Men do it as they get older because they are going bald and it's just easier to hide it that way. People do it for cancer charities to make wigs out of their hair. People (Birtney Spears) do it when they are not sure how else to express their feelings.