Doctors recommend a balanced diet consisting of whole grains, lean meats and seafood, and fresh vegetables and fruits for those undergoing chemotherapy treatments, according to WebMD. Eating small meals on a regular schedule prevents hunger. Rice, apples and bananas combat diarrhea, while beans and lentils prevent constipation.
A well-rounded diet helps ward off infection, rebuild tissue and limit the amount of side effects a patient feels from chemotherapy treatments, explains the American Cancer Society. Adequate protein from poultry and fish encourages hair growth, skin repair and muscle integrity. An increased water intake protects kidney and bladder functions as well. Foods rich in nutrients, such as avocados, nuts, cooked cereals and soups, pack the necessary calories to maintain a healthy weight during cancer treatments, according to WebMD.