Radiation affects all your cells that are in the radiation field, normal ones as well as cancer cells. That means you may have side effects. What they are and how strong they are depends on these things:
Whether you are also getting chemotherapy
What part of your body is treated
Improvements in radiation treatment may reduce side effects. For instance, intensity modulated radiation therapy (IMRT) precisely targets the area to be radiated, which may help preserve nearby healthy tissue.
These are common side effects of radiation:
Loss of appetite
Loss of saliva
Dryness in the mouth that may occur after radiation can become a permanent problem. A dental exam and extraction of any teeth in poor condition is needed before radiation. Whether all of the teeth or just some of them will need to be extracted depends on the extent of radiation fields and the dentist. Dentures can be fitted after surgery or radiation.