Dietary tips to help ease side effects

Dietitian, Berna Harmse, shares effective dietary tips to help ease side effects caused from cancer treatment.

There are many ways of improving your nutritional status as a cancer patient. If you have any difficulty in following these guidelines, it might be helpful to see a dietitian to give you information that is perfectly suited to your personal needs.

All methods of treating cancer (chemotherapy, radiation and immunotherapy) are powerful. Each person reacts differently, but only about one third of patients receiving active cancer treatment suffer side effects and these side effects usually go away after treatment. 

Remember that with everything in life, moderation is the key. Don’t overdo anything, especially if you are considering diet supplementation in pill or potion form. Always contact your healthcare provider before embarking on something new, even exercise.

Nausea and vomiting

  • Eat small, frequent meals. 
  • Food is best tolerated at cool or room temperature.
  • Eat dry salty crackers, pretzels, biscuits or cookies.
  • Simple foods, such as rice, scrambled eggs, toast, noodles, bananas, mashed potatoes, custards may be better tolerated. 
  • Drink enough liquids; opt for clear, cold non-acidic liquids.
  • Eat light, low-fat foods.
  • Allow plenty of fresh air in the house.
  • Disperse cooking odours.


  • Milk products;
  • Cream soups;
  • Fatty/fried foods;
  • Sweet desserts;
  • Avoid lying down immediately after eating.

Sore mouth and throat

  • Eat soft, moist food at cool or room temperature (mashed potatoes, macaroni or casseroles).
  • Drink through a straw.


  • Spicy, salty or acidic foods;
  • Carbonated beverages;
  • Juice, especially citrus;
  • Bananas;
  • Crisp or raw foods;
  • Hard/tough meats;
  • Textured or granular foods;
  • Coarse bread products;
  • Extremely hot or cold foods.

Dry mouth

  • Eat foods with a high moisture content (serve with gravies or sauces).
  • Have liquids with food.
  • Drink extra liquids between meals.
  • Chewing of sugarless gum or sucking of mints may help.
  • Concentrate on good oral hygiene.


  • Thick liquids;
  • Thick hot cereals;
  • Dry foods, bread products, tough meats, crackers;
  • Excessively hot foods;
  • Alcohol.

Early satiety

  • High-calorie diet with calorically dense foods.
  • Meat, fish, poultry, eggs, whole milk, cheese, cream soups, ice cream, whole-milk yoghurt, creamed vegetables, rich desserts.
  • Small, frequent feedings.
  • Use of calorically dense supplements.


  • Low-fat or non-fat milk products;
  • Broth-based soups;
  • Green salads;
  • Steamed, plain vegetables;
  • Low calorie beverages.


  • Eat smaller more frequent meals. 
  • Fluid replacement is essential to prevent dehydration. Drink water or rehydration drinks after every loose stool.  

Home recipe for oral rehydration therapy:

1 litre of cooled cooked water 

8 teaspoons of sugar

1/2 teaspoon of table salt 

  • A low fat and low dairy diet may be indicated (damaged to the surface of the gut may cause intolerance to lactose; drinking milk or eating milk products can cause cramps, abdominal distress and diarrhoea in some people). 
  • Moderate the intake of fibre. Concentrate on soluble fibre (fruit, oats, and legumes). 
  • Limit the intake of fructose (fruit sugar) by avoiding pear juice as well  as grapes, honey, dates, nuts, figs and soft drinks. 
  • Eat bananas, potatoes, fish, meat and drink apricot juice, tomato juice to replenish sodium and potassium. 
  • Eat foods that have been brought to room temperature.


  • Avoid gas-forming foods and drinks (peas, lentils, cabbage, cauliflower, broccoli, onion, nuts, cucumber, beans and bran, garlic, beer). 
  • Avoid alcohol and caffeine, since both may have a dehydrating effect.


  • Regular diet with fibre added (whole grains, dried fruit such as prunes, even prune juice, bran, etc.). Fibre-enriched supplements/ bulking agents may be beneficial.
  • Extra fluids and exercise can be beneficial.


  • Gas-forming foods and beverages.
Berna Harmse is a private practicing dietitian. She holds a MSc in Dietetics, and has a special interest in oncology nutrition. She is also an external lecturer at Stellenbosch University Division of Human Nutrition.

MEET THE EXPERT – Berna Harmse

Berna Harmse is a private practicing dietitian. She holds a MSc in Dietetics, and has a special interest in oncology nutrition. She is also an external lecturer at Stellenbosch University Division of Human Nutrition.

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