Cancer and nutrition

Eating healthfully is a common problem for people who have cancer. More than 25 percent of cancer patients lose their appetites at some point, and the problem affects nearly everyone in the advanced stages of cancer. Even when plenty of calories are consumed, about 50 percent of cancer patients develop a condition known as cachexia. This condition is characterized by weakness and loss of appetite, body weight, fat and muscle (often due to problems absorbing nutrients from food).


Causes/associated factors
Cancer and its treatment affect the body in many ways. Common treatment options such as surgery, chemotherapy, radiation therapy, medications and immunotherapy may have many side effects, in addition to the effects of the cancer itself.
For example, cancerous tumors contribute to altered metabolism. In turn, this can lead to protein breakdown, glucose intolerance and decomposition of fat. During the advanced stages of cancer, it's difficult to reverse such changes through consuming additional calories.


Signs/symptoms
Sometimes, nutrition problems have no symptoms. In other cases, you may notice weight loss, appetite loss, an inability to eat or feeling full after eating a small amount of food. You may also notice changes in your sense of taste or smell. Physical changes may include pain, diarrhea, constipation, sore and dry lips and tongue, and difficulty swallowing. Sometimes, tumors (abnormal tissue growths) obstruct the gastrointestinal tract.
Other symptoms of inadequate nutrition include:

skin conditions or bruising
hair thinning and shedding
eye problems, including vision changes
mouth sores
bleeding gums
goiter (a swelling in the front part of the neck caused by enlargement of the thyroid gland)
abdominal distention or enlarged liver
limb swelling
bone, joint or muscle discomfort
neurological changes, such as loss of reflexes or altered mental activity
anemia (a condition marked by a decreased number of red blood cells or hemoglobin, a protein in red blood cells that contains iron)

Diagnosis
To diagnose nutrition problems, the doctor will examine your medical and diet history, ask about your food intake and do a physical exam. Your weight and height will be measured. Other measurements may also be taken, such as skinfold thickness to help estimate body fat. Daily or weekly weigh-ins may be needed.
Blood samples may be taken to measure your blood count, as well as the levels of certain proteins in your blood, including albumin (a protein that helps maintain blood volume and blood pressure) and transferrin (a protein that carries iron). Urine samples may be used to measure your nitrogen balance (a calculation of the amount of protein your body absorbs and excretes). The results of your lab tests may influence your treatment options.


Treatment
Treatment depends on the stage of cancer and severity of nutritional deficiency. Sometimes, simple lifestyle changes are adequate. Consider these tips to combat appetite loss:
Eat small meals every two to three hours or when you have the most energy. Eat with friends to boost your spirits.

Eat foods high in calories and protein, and take nutritional supplements as recommended by your doctor. To increase caloric intake, top foods with butter, honey or brown sugar.

Avoid strong-smelling foods if they're bothersome.

Avoid drinking with meals, except to treat dry mouth.

Stimulate your appetite with light exercise.

Eat lightly on the morning of chemotherapy.
Consider these tips to help with changes in taste:

If regular flatware gives a metallic taste to the food, use plastic utensils.

Marinate meat with sweet or savory sauces or use extra flavorings, depending on personal preference. Try serving meat chilled instead of hot.

If red meat isn't appealing, try poultry, fish, beans or eggs. Milk shakes, pudding and cheese are also high in protein.

Rinse your mouth before eating.
Consider these tips to combat dry mouth:

Eat soft or moist foods. You can also process foods in the blender.

Moisten foods with sauces, gravies or oils.

Avoid extremely hot, cold, sticky or rough foods.

Avoid salty foods.

Try tart foods and drinks (lemonade, for example) to help increase your saliva production. Chewing sugar-free gum or sucking on hard sour candy, frozen grapes or frozen juice bars may also be effective.

Take small bites, and chew thoroughly.

Practice good oral hygiene. Use a soft toothbrush and diluted mouthwashes.

Try an artificial saliva or saliva-stimulating product.
Your doctor may prescribe medication to improve your appetite or combat nausea. In severe cases, intravenous nutritional support or tube feedings directly into the gastrointestinal tract may be needed.


Complications
Malnutrition can have a negative impact on the effectiveness of cancer treatment. The distress caused by poor eating may affect the entire family, especially if your nutritional difficulties are prolonged. Helping loved ones understand the underlying causes of poor nutrition and how to help can be beneficial for everyone. Because eating is often a social event, losing your appetite may lead to isolation. To avoid feeling forgotten and alone, attend as many group meals as possible.

Prevention
Proper medical care and early intervention are vital in preventing nutritional complications. A team of health care professionals including a registered dietitian and nurse can assess, plan and guide your treatment plan to help prevent or minimize complications. If you haven't consulted a dietitian, ask your doctor for a referral.