why does you hair fall out when you have cancer because my grandad did but his hair didn’t fall out?

Question: why does you hair fall out when you have cancer because my grandad did but his hair didn't fall out?
- Keywords:
  cancer,
  chemotherapy,
  hair,
  illness
Asked by ilovescience2991 to Cathal, Daphne, Darren, Jon, Katherine on 16 Mar 2012.
- Katherine Haxton answered on 16 Mar 2012:
  
  Some drugs used to treat cancer – chemotherapy – affect the cells that hair grows from which causes hair to fall out. So it depends on the type of cancer, and what drugs are used to treat it. When a person gets drugs to treat cancer, they get to every cell in their body, not just the cancer ones. That’s what causes the side effects like hair falling out, or feeling sick, or having sore hands or feet.

Question: why does you hair fall out when you have cancer because my grandad did but his hair didn't fall out?