Hard training makes simple food work harder. After a run, lift, ride, swim, or long practice, the body needs protein to repair muscle, carbohydrates to refill energy stores, fluids to rehydrate, and minerals to replace what sweat takes away.

Cancer treatment can change nearly everything about eating. Appetite may drop. Mouth sores can make chewing hard. Smells may feel too strong. Foods that once tasted comforting may turn metallic, bitter, or too rich.