Gina, there are ways of boosting the calories without actually eating more in terms of volume. For example, add skim milk powder to whole milk to make fortified milk and then use the fortified milk to make smoothiies. Try to eat a lot ( I told people I was fattening up my husband) prior to treatment and eat all your favorite foods to your heart's desire. I tried very hard to keep my husband at 2000 calories a day and still, he lost weight in the course of the treatment. I totally agree with Christine that you need as much energy as you can find to fight the cancer and to help the body repair itself. Hydration is vital, it can make the difference between a feel-good day and a crappy day.