Using diet to alleviate the side effect of cancer treatment

Nowadays, there is no study indicating that food reduction can kill cancer cells or reduce their spread. Hence, please do not listen to rumour. For cancer patients, they should continue to feed and avoid weight loss. If weight loss is too high, it can affect quality of life, reduce the treatment effect and survival rate. Patient with cachexia will lose appetite, lose muscle and weight because of altered metabolism. It is common cause of death of cancer patients and lead to 5 to 25% of mortality.1-4 Hence, weight is vital to survival rate. If one loses 5% of weight in 1 month or 10% in 6 months, one is malnutrition. He or she should consult dietitians immediately for nutritional assessment and treatment. The early the intervention, the more effective the treatment will be.

During the treatment period, one can consider to take 2g of EPA daily. According to clinical study, EPA may inhibit weight loss, improve appetite. For more details, please consult your registered dietitian.

Anorexia is common problem in cancer patients. Eating in calm and comfortable environment with regular exercise can help improve appetite. Smaller volume but higher frequency diet, eating small portion of high protein content and high energy food in every 1-2 hours in replacing 3 big meals, can help this kind of patients.

The appetite is usually better in the morning. One can eat high calorie, high protein during the breakfast, such as toast with banana and peanut butter, omelet with cheese and ham, sandwich with tuna or macaroni with minced meat. Besides, the recipe can be modified, e.g. adding salad dressing in sandwich, adding cheese in the spaghetti, adding butter in mashed potato and milk, adding more sugar and milk in cold and hot drink. All of them can add extra calorie and protein. If there is difficulty in swallowing solid food, one can choose nutritional supplement, fruit juice, milk shake and dessert (such as sesame candy and almond soup). They are soft in texture and are easy to swallow.

To alleviate her problem, you can try smaller volume but higher frequency diet. If she does not like red meat, you can try poultry, fish, egg and other soya product for replacement.

If she feels bitter, you can add sweet sauce, seafood sauce or peanut butter or drink fruit juice and honey to cover up the bitter taste. If she finds food tasteless, you can add more salt, garlic, sugar, cheese, ham, celery, onion, pickled vegetable or herbs to strengthen the taste. Besides, meat can be served with pineapple or peach.

If she tastes metal, you can use plastic utensils to reduce bitter taste. Do not use canned drink or metal cup. Food with sour taste can help reduce the metal taste e.g. fruit juice. Lastly, rinse the mouth before eating can also improve the situation.

Drink enough liquid can improve the dryness situation. You can bring water along the way and keep the oral cavity wet. Patient can also eat wet food, e.g. soyabean curd, soft rice, cereal, and mashed potato. Add extra sauce e.g. soup, meat sauce and margarine. Eating very sweet or sour food can stimulate more saliva (This method is not suitable for patient with pain in oral cavity). Use straw to drink liquid food. Avoid eating very salty food because it can cause dryness. Putting ice inside the mouth, chewing hard candy or chewing gum can also stimulate saliva. If necessary, rinsing the mouth more often can keep your oral cavity healthy.

You can cut the food into pieces and cook until it becomes soft. You can eat soft food which is easy to chew and swallow which includes soft fruit (banana, mashed fruit, cooked pear or apple etc), mashed potato, noodle, milk shake, cereal, soyabean curd etc. Besides, you can blend the vegetable and food to make it smooth. Or you can add meat soup or sauce into the food.

Beside normal meal, you can drink high energy, high protein nutritional supplement and choose cold or warm food. Moreover, please avoid food which is too hot, spicy such as alcohol, orange, lemon and grapefruit, spicy or salty food, coarse or dry food (potato chip, biscuit, toast, dry cereal). Remember to clean your teeth (including false tooth) after every meal and before sleep. Keep your mouth clean and prevent infection.

Patient can eat less with more frequent meal and avoid food which has too strong taste, too sweet and too oily. He can try dry food (such as toast, biscuit, fried ginger rice). Cold or warm food is more easily acceptable. Eat slowly with chewing can help digestion. If appetite is bad because of vomiting, he can try nutritional drink to supplement the regular meal. If he feels vomiting in the morning when he wakes up, he can eat a little soda biscuit on the bed. On the other hand, speak less before eating can help and avoid too much air entering into the stomach. At the same time, he should stay away from smoke, fragrance and mist. If the situation is serious, patient can ask the doctor to prescribe anti-vomiting medicine.

Persistent diarrhea can cause dehydration or the body deficient of important minerals such as sodium and potassium. Patient should eat less with more meals and try to drink fluid such as water or rice water during diarrhea to alleviate the situation. It let the intestine rest and replenish the water loss. When the diarrhea situation is improved, patients can slowly increase the portion of food with low residue and solid food, such as congee, white bread, white rice, mean meat, fish or cooked egg.

Sports drink can replenish the loss of sodium and potassium because of diarrhea. At the same time, drink sufficient warm fluid. Avoid drinking coffee, alcohol, milk, fruit juice and carbonated drink, or eating food which is fried, oily, too sweet, too strong taste. Avoid chewing sugar free chewing gum or candy, high fibre food (e.g. full cereal food, bean or nuts). Should choose vegetable with low residue (e.g. young leaves, squash or melon without skin or seed). Reduce the portion of vegetable. If the situation is serious, please consult the doctor to prescribe anti-diarrhea medicine.

If you have less than three times per week, feces are in particle shape and are hard, you need to push hard and feel jammed, these are symptoms of constipation. This is common in cancer patients. They can drink 8-10 liquid (e.g. water, tea, soup, milk or grapefruit juice), eat more high fibre food e.g. whole wheat bread, cereal bread, red rice, coarse rice, cereal, vegetable, fruit, bean. Regular jogging and exercise can help intestine movement. If necessary, you can consult your doctor to prescribe medicine.

Patients should eat more slowly and avoid eating food which creates gas such as bean, onion, corn, cabbage, milk, carbonated drink. Slow walking can help ease the problem. Avoid eating chewing gum. Do not speak during eating to avoid inhaling too much air. If situation is persistent or worsen, please consult your doctor.

Breast cancer patient may gain weight during chemotherapy because of eating too much high calorie food or not doing exercise during the therapy. Hormone therapy such as female hormone is also possible reason to gain weight. If you weight is increased, it would be better for you to consult registered dietitian for weight reduction plan after the chemotherapy is finished.

This is the symptom of Dumping Syndrome. The volume of stomach after the surgery is reduced. It makes the food entering the small intestine too soon and stimulates body to stimulate large amount of insulin which cause very low blood sugar level. It makes people feel dizziness, sweating and faint. This usually happens in half hour to 2 hours after meal. It is suggested to eat less with more meal, to eat complex carbohydrate e.g. rice, bread and macaroni to delay the time of food entering the small intestine so that the blood sugar level can be maintained in relatively stable level. Since candy, sweet soup, carbonated drink, fruit juice contains lots of sugar which can be easily absorbed, they should be avoided. At the same time, avoid drinking fluid when having meal.

Radiotherapy, chemotherapy or cancer can reduce the white blood cells level which can increase the chance of infection. To reduce the chance of infection, one has to avoid uncooked egg, fish, rotten or damaged fruit and vegetable, damaged packaged food, expired food, salad bar or buffet.

Meat, poultry and fish needs to be fully cooked. Food should be defrosted in microwave oven, in refrigerator, or in running water. Do not defrost in room temperature. Food should be cooked immediately after defrost. Hot food and cold food should be kept in right temperature. Unfinished food should be frozen within 2 hours and should not be stored in more than 3 days and should not reheat more than once. To reduce unfinished food, it would be good practice to buy small quantity packaged food or cook in smaller quantity. Knifes and chopping boards for raw and cooked food should be separated to minimize cross infection. In personal habit, one should use liquid soap to wash hands to prevent germ from spreading.

Late stage cancer patients have palliative care which includes nutrition therapy and/or medicine therapy to alleviate the pan and maintain quality of life and to keep balanced nutrition. The need of late stage cancer patients may vary. For late stage cancer patients, most food is accepted because patients always have problem with body function because of loss of appetite. Hence, one should encourage the patients to eat what they like. If they have problems with eating, they should consult registered dietitian for professional advice and consider to have nutritional supplement with proper exercise to increase appetite.

Cancer and Malnutrition

Cancer patient usually have problem of malnutrition and weight loss5

Depends on type and severity of cancer, around 31% to 87% of cancer patients will have weight loss situation6

Reasons why cancer can affect the nutrition intake of patients:

  • Reduced food intake: Cancer can change patient taste, reduce appetite and even anorexia
  • Body Abnormality: Cancer may affect body metabolism
  • Side effect of cancer treatment: Vomiting, constipation, diarrhea, mucositis, oral inflammation, dysphagia
  • Emotional problem: Depression, distress, worry

Malnutrition is important!

Cancer patients should pay attention to malnutrition or weight loss. If the situation is not handled properly, it can have serious problem:6,7

  • Affect the efficacy of treatment
  • Increase the side effect of treatment
  • Reduce immunity
  • Reduce patient mobility
  • Reduce quality of life
  • Affect survival rate
  • Reduce wound healing ability

There are special nutritional supplements for cancer patients in the market. They can provide high energy, high protein and EPA which can reduce side effect and improve malnutrition situation (for more details, please refer to production information – cancer)

The above information "Using diet to alleviate the side effect of cancer treatment" is provided by Ms. Sally Poon

Ms. Sally Poon

Registered Dietitian (UK)
Registered Dietitian (Australia)
Bsc Nutrition (King’s College London)
Master of Nutrition & Dietetics (University of Sydney)
HKU Space Sports Nutrition

Ms. Poon is private practice registered dietitian. She provides versatile medical nutrition therapy, including cancer, weight management, diabetes, high blood pressure, high blood lipid, renal disease, fatty liver, metabolic arthritis, sports nutrition, geriatrics nutrition and feminine health. According to each person medical history, medicine, body characteristics and diet, personalized nutritional therapy can be provided. Ms. Poon is also always being invited as speaker for cancer nutrition talk and cooking workshop.

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  2. Inagaki J, Rodriguez V, Bodey GP. Proceedings: causes of death in cancer patients. Cancer 1974;33(2):568–73.
  3. Ambrus JL, Ambrus CM, Mink IB, Pickren JW. Causes of death in cancer patients. J Med 1975;6(1):61–4.
  4. Warren S. The immediate causes of death in cancer. Am J Med Sci 1932;184:610–5
  5. Supportan® Powder Enteral Nutrition Formula Adapted to the Special Needs of Cancer Patients (Revised on 17th March 2014).
  6. Arends J. Bodoky G. Bozzetti F, et al. ESPEN Guidelines on Enteral Nutrition: Non-surgical oncology. Clin Nutr. 2006;25:245-259.
  7. Agilsés JM. Cancer-associated malnutrition. Eur J Oncol Nurs. 2005;9 Suppl 2:S39-50.