Many people with cancer have a hard time maintaining good nutrition since the cancer itself and the therapies that fight it can make it hard to eat enough food. ( See Coping with Treatment .) There are several major common problems.
• Loss of appetite This is the most serious problem. Pain, nausea, vomiting, diarrhea, constipation or a sore or
dry mouth can easily make you lose interest in food. You may also tend to eat less because of fear, anxiety or
depression about having cancer.
• Malabsorption For a number of reasons, nutrients may not be absorbed normally into the bloodstream from
the intestines. Cancer of the pancreas can cause a decrease in the digestive juices that regulate absorption.
Abnormal connections between surgically created loops in the intestine may divert food past the parts of the
intestine where nutrients are usually absorbed. The intestines may become less able to absorb nutrients if your
normal food intake is reduced for a lengthy time.
• Physical problems Tumors in the mouth and neck area, as well as radiation therapy directed to those areas, can
make it hard to swallow or cause pain in the mouth or throat. Radiation directed to the abdomen or the removal
of part of the stomach or intestinal tract can cause diarrhea, cramps or decreased absorption.
• Changes in smell and taste Chemotherapy or radiation to the neck and mouth can distort the perception of
smell and taste, and the loss of taste tends to be greater if the tumor is more advanced. Some foods can start to
taste bitter or rancid, especially meat, which might taste bitter and metallic. It is common to develop strong
aversions to foods such as meat, eggs, fried foods or tomatoes. All these changes make your appetite worse,
making it even more difficult for you to avoid weight loss.