Stomach cancer and weight loss

For many people, the side effects of cancer and treatment make it difficult to eat enough to stay at a healthy weight. Weight loss is a very common symptom for people with cancer, particularly in people with:

  • stomach cancer
  • pancreatic cancer
  • oesophageal cancer (cancer of the food pipe)

Weight loss is often associated with loss of appetite. This is not the only reason for losing weight. You might be eating normally, but your body may not be absorbing all the nutrients in the food you eat so you will still lose weight.

This can be very upsetting and worrying. Speak to your clinical nurse specialist or dietician about any eating problems. They will get you any help that you need.

Having stomach cancer will affect eating and drinking habits, whatever the stage of cancer or the treatment. People who have had all (or part of) the stomach removed will need to adjust the amount they eat at one time.  Over one day, you should eat the same amount of food you normally would. But split it into smaller, frequent meals (about two hourly).


Keeping a food diary

Many people find that certain foods upset their digestion. Which foods do this varies from person to person. Trial and error is really the only way to find out if a particular food upsets you.

Keep a food diary for a couple of weeks. Write down in one column what you eat and the time and date.

In a second column, write down any diarrhoea, sickness or other digestion problems you have. You can then look back and find out which foods upset your system.

Increasing calorie intake

To put on weight you need more calories. Eating a high calorie diet can be difficult. Fat is the best way to get concentrated calories.

After surgery to the stomach, you may find it difficult to tolerate high fat foods. You could try ready made liquid meals for extra calories, as well as your usual diet.

You can get these on prescription from the GP. You can buy commercial brands, such as Build Up or Complan at your local chemist.

Vitamin and mineral supplements

After stomach surgery, your doctors may advise you to take extra calcium, vitamin D and iron. These nutrients are normally absorbed in the stomach.

Having all or part of the stomach removed may mean you can't absorb enough from a normal diet. You may need to have injections of Vitamin B12.

Seeing a dietician

There will be a dietician working in the team looking after you. Your doctor or nurse will refer you to them.

A dietician will be able to offer support and advice to you and any family members. You should see your dietician regularly. If you have concerns you can ask for an appointment at the hospital where you had treatment.

Problems with eating and nutrition can cause a lot of distress and anxiety. Many people having these problems will need a great deal of emotional support so don't feel you are being a nuisance. This is a very important part of your recovery.

Last reviewed: 
17 Jan 2020
  • Guidelines for the management of oesophageal and gastric cancer
    British Society of Gastroenterology (BSG), 2011

  • Postgastrectomy complications
    UpToDate, Accessed 2014

  • Principles and practice of oncology (9th edition)
    De Vita and others
    Lippincott, Williams and Wilkins, 2011

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