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Managing side effects

Stomach and oesophageal cancers and their treatment can cause side effects. Some of these side effects are permanent and may change what you can eat, and how you digest foods and absorb essential nutrients. This section explains common side effects and how to manage them.

How treatment will affect eating

During and after treatment, you need to eat and drink enough to get the nutrition you need, maintain your weight and avoid dehydration. If you are eating less than usual, it is often recommended that you have high energy and high protein foods and relax healthy eating guidelines. You may need a feeding tube during or after treatment if you are unable to eat and drink enough to meet your nutritional needs. Ask your doctor for a referral to a dietitian with experience in cancer care, who can give you more information.

After treatment, some foods may be uncomfortable to eat and may cause digestive problems. You will need to try different foods and change your eating habits, such as eating smaller meals more often throughout the day.

You may find it hard to accept the differences in how and what you can eat. It’s natural to feel self-conscious or worry about eating in public or with friends. It may help to let your family and friends know how you feel, or to speak with a counsellor or someone who has been through a similar experience. They may be able to give you advice on how to adjust. It may take time and support to adapt to your new way of eating.

Download our booklet ‘Nutrition and Cancer’

After surgery, your stomach will be smaller (or completely removed) and you will feel full more quickly after a meal. You may not feel like eating or you may have lost your sense of taste. It is important to maintain your weight to avoid malnutrition. Even a small drop in your weight (e.g. 3–4 kg), particularly over a short period of time, can make your recovery slower.

Chemotherapy and radiation therapy can cause nausea, irritation to the oesophagus or a sore mouth. These side effects may make eating uncomfortable.

How to prevent unplanned weight loss

  • Have a snack or small meal every 2–3 hours if you have lost your appetite and don’t feel hungry.
  • Keep a variety of snacks handy (e.g. in your bag or car).
  • Eat when you feel hungry or crave certain foods. Eat slowly and stop and rest when you are full.
  • Avoid filling up on liquids at mealtimes, unless it’s a hearty soup, so you have room for nourishing food.
  • Try to drink fluids that add energy (kilojoules), such as milk, milkshakes, smoothies or nutritional supplement drinks recommended by your dietitian.
  • Prevent dehydration by drinking fluids between meals (30–60 minutes before or after meals).
  • Try eating different foods to see if your taste and tolerance for some foods have changed.
  • Ask your dietitian how you can increase your energy and protein intake.
  • Don’t eat for a few hours before bed. It may make you uncomfortable, bring on reflux and disturb your sleep.

You may have difficulty swallowing (dysphagia) before, during or after treatment. This may be because of where the tumour is or because of swelling in the oesophagus after surgery. Signs that swallowing is difficult include taking longer to chew and swallow, coughing or choking while eating or drinking, or food sticking in your mouth or throat like a ball. These symptoms should ease after 10–12 weeks.

Some people find that food and fluid goes into the windpipe instead of the food pipe. This is called aspiration and it can block the airways and make breathing difficult.

How to eat when it is hard to swallow

  • Change the consistency of what you eat by chopping, mincing or pureeing.
  • Make food softer (e.g. mash food or use a slow cooker) to keep it moist.
  • Between meals, snack on soft foods, such as avocado, yoghurt, ice-cream, diced tinned fruit and drink milkshakes.
  • Chew carefully and slowly, sitting still and upright. Try to avoid talking while eating.
  • Avoid dry foods – add extra gravy or sauce to your meals.
  • Wash food down with small sips of fluid.
  • Talk to your doctor or dietitian if you are losing weight. They can help you find foods that give you enough nutrition and help you maintain your weight.
  • See a speech pathologist for suggestions on the types of foods to include and ways to eat and drink safely.
  • Add nutritional supplement drinks to your diet to help maintain your strength. Examples include Sustagen, Resource and Ensure.

Stomach acid going back into the oesophagus (reflux) is common after surgery for oesophageal cancer. This can cause heartburn, chest discomfort, or your stomach contents to flow up your oesophagus, particularly when lying flat or bending over. Taking medicines to reduce stomach acid generally helps.

After surgery or radiation therapy for oesophageal cancer, scar tissue may cause choking or swallowing problems while eating or drinking. See your doctor if this continues. After an oesophagectomy, the stomach can take longer to empty. You may feel full more quickly or be more likely to vomit or bring up food after eating.

How to reduce reflux and choking

  • Limit spicy foods, fatty foods, fizzy drinks, alcohol and citrus fruits to prevent reflux.
  • Take small sips of liquid to reduce coughing or choking.
  • Chew foods well, eat slowly, and don’t talk while eating.
  • To help food digest, sit up straight when eating and for at least 30 minutes after.
  • Have your main meal earlier in the day and eat a small snack in the evening.
  • After an oesophagectomy, stay upright for 2–4 hours after eating. Eat your evening meal more than four hours before going to bed.
  • Avoid positions where your head is below your stomach (e.g. when bending over too far), particularly after eating.
  • Keep your chest higher than your stomach when sleeping by lifting the head of your bed with blocks about the thickness of a house brick. The whole bed should be tilted slightly.
  • Ask your doctor how much physical activity you can do, as this can sometimes cause reflux.

If surgery has changed the structure of your stomach, partially digested food can go into the small bowel too quickly. This can especially be a problem with fluids containing high amounts of simple sugar, such as soft drinks, juices and cordial. You may have cramps, nausea, racing  heart, sweating, bloating, diarrhoea or dizziness. This combination of symptoms is called dumping syndrome. Symptoms usually begin 15–30 minutes after eating.

Sometimes symptoms occur 1–2 hours after a meal. These are called late symptoms, which tend to cause weakness, light-headedness and sweating, and are usually worse after eating foods high in sugar.

How to manage dumping syndrome

  • Have small meals throughout the day. Chew your food well.
  • Eat slowly so your body can sense when it is full.
  • Surgery may affect how you tolerate certain foods. Keep a record of foods that cause problems and talk to a dietitian for suggestions on what to eat to reduce the symptoms.
  • Avoid eating highly processed foods and eat fresh, unprocessed foods.
  • Avoid foods and drinks high in sugar (e.g. cordial, soft drinks, cakes and biscuits). Eating large amounts of these foods can lead to diarrhoea and pain.
  • Eat meals high in protein (e.g. lean meats and poultry, fish, eggs, milk, yoghurt, nuts, seeds and legumes/beans).
  • Eat starchy foods (e.g. pasta, rice or potato).
  • Drink liquids between meals rather than at mealtimes.
  • Symptoms usually improve over time. If they don’t, ask your doctor for advice about medicines that may help.

Surgery to remove the stomach will mean you will be unable to absorb some vitamins and minerals from food. This may lead to low levels of:

  • calcium – over time, your bones may become weak and brittle, and break more easily (osteoporosis), which may cause pain
  • vitamin B12 – low B12 levels can cause a condition called pernicious anaemia. The most common symptom is tiredness. Other symptoms include pale skin, breathlessness, headaches, a racing heart and appetite loss. You will need regular vitamin B12 injections after a total gastrectomy, and may need vitamin B12 injections if your levels are low (without having had total gastrectomy)
  • iron – low iron levels can cause iron deficiency anaemia. You may need iron supplements, which are usually given as an intravenous (IV) infusion because iron taken by mouth can’t be absorbed easily

Tips for managing anaemia

  • Talk to your doctor if you have symptoms of anaemia or osteoporosis.
  • Find out what type of anaemia you have and how to treat it.
  • Rest when you need to and try not to do too much.
  • Eat foods rich in iron, such as meat, eggs and softened dark green leafy vegetables.
  • Eat foods high in vitamin C (e.g. red or orange fruits and vegetables) to help your body absorb iron from iron-rich foods, especially plant-based sources.
  • Avoid drinking tea and coffee with meals, as these can prevent your body absorbing iron.
  • If you smoke, talk to your GP about quitting or call the Quitline on 13 7848 for support and information. Smoking tobacco can make symptoms worse.

Featured resources

Oesophagogastric cancer - Your guide to best cancer care

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Understanding Stomach and Oesophageal Cancers

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This information is reviewed by

This information was last reviewed October 2021 by the following expert content reviewers: Dr Spiro Raftopoulos, Gastroenterologist, Sir Charles Gairdner Hospital, WA; Peter Blyth, Consumer; Jeff Bull, Upper Gastrointestinal Cancer Nurse Consultant, Cancer Services, Southern Adelaide Local Health Network, SA; Mick Daws, Consumer; Dr Steven Leibman, Upper Gastrointestinal Surgeon, Royal North Shore Hospital, NSW; Prof Michael Michael, Medical Oncologist, Lower and Upper Gastrointestinal Oncology Service, and Co-Chair Neuroendocrine Unit, Peter MacCallum Cancer Centre, VIC; Dr Andrew Oar, Radiation Oncologist, Icon Cancer Centre, Royal Brisbane Hospital, QLD; Rose Rocca, Senior Clinical Dietitian: Upper Gastrointestinal, Nutrition and Speech Pathology Department, Peter MacCallum Cancer Centre, VIC; Letchemi Valautha, Consumer; Lesley Woods, 13 11 20 Consultant, Cancer Council WA.