Sometimes, especially during or soon after treatment, you may not feel like eating. You may be uncomfortable or tired. You may find that foods do not taste as good as they used to. In addition, the side effects of treatment (such as poor appetite, nausea, vomiting, or mouth sores) can make it hard to eat well. Your doctor, a registered dietitian, or another health care provider can suggest ways to deal with these problems. Also, the NCI booklet Eating Hints for Cancer Patients has many useful ideas and recipes. Page 46 tells how to get NCI booklets. Many people find they feel better when they stay active. Walking, yoga, swimming, and other.