Cancer and weight gain

Thursday 24 May 2018

Summer is coming, and we’re sneaking out of hibernation. For some of you, the last few months or years may have been spent in cancer treatment, or trying to resume some sense of normality after a long spell of treatment.  Alternatively, you may be on the ‘watch and wait’ scenario, where treatment is not yet required, but you are being monitored by your medical team.

Most of us think of cancer treatment as debilitating, and as such, weight loss may be expected. For many this does happen, but for others weight gain becomes the issue. It could be due to medications such as steroids and hormone therapy, for example. In women, treatment induced menopause can add to weight gain. Sometimes, the cause may be the inability to undertake much exercise whilst on chemo or radiotherapy.  

You may recognise an element of ‘comfort eating’, an emotional response to the stresses of trying to deal with a major life changing event. In other cases, friends and family, determined to ‘build you up’ bring lots of delicious goodies which would seem churlish to refuse. They may be thinking you’ve been through so much, and need tempters and rewards.

To be honest, a small increase in weight during cancer treatment is usually not a problem.  The worry is more about significant weight gain, and its impact on your future health.

Cancer.Net website notes that  ‘Weight gain is an especially important health issue for women with breast cancer because more than half experience weight gain during treatment. Reports have shown that weight gain during treatment is linked to a poorer prognosis (chance of recovery). Being overweight before treatment begins also increases the risk of serious health conditions, such as high blood pressure, diabetes, and cardiovascular disease’

It’s also something that we can actively do something about and regain some control, helping our bodies to deal with what life throws at it by losing the pounds gained over time.  

There is useful advice on this, in a variety of places on the internet (see resource list at end of my blog).

Tips to lose weight

First of all, it is difficult to lose weight whilst you're on cancer treatment - and if you're having regular, active treatment, like chemotherapy or radiotherapy - it's possibly not the time to try. Even if you've finished treatment, If you're thinking of going on a diet, do check with your GP or health care team.

  • Let people know you're trying to lose weight. Family and friends can encourage you, rather than try to feed you up too much. 
  • It's better to lose one or two pounds a week, rather than go a crash diet - weight loss is more often maintained when it falls off gently,
  • Sort through your cupboards, and throw/give away the temptations in there - biscuits, crisps, treats, etc. Low fat options of foods are helpful, but do check their hidden sugar content - the flavours can sometimes be enhanced by sugar, which doesn't really help when you're trying to lose weight.
  • Incorporate exercise into your life. Walking, cycling, gardening, can all help, for example. As a cancer survivor, aiming for about about 150 minutes exercise per week, as well as strength building  exercises two or three times a week, is an ideal. Do the exercise in short bursts, rather than overdoing things. Check with your GP/healthcare team that it is OK to do so.
  • Drink plenty of fluids, avoiding high calorie drinks and alcohol.
  • Smaller portions help - and perhaps using a smaller plate can help create the illusion of volume. 
  • Eating a balanced diet with plenty of fruit and vegetables helps with your general health as well as weight loss.

(I'm aware that not everyone reading this will be worried about putting on weight. You may be a carer or someone with cancer who is more concerned about weight loss, appetite and taste changes, and what to do to improve the situation).

There can be a great deal of baffling and confusing information about weight issues and nutrition, and you may be experiencing some new emotions due to your body's physical changes.

You might be interested to read further advice concerning weight changes on our website, or alternatively pop into one of our Maggie’s Centres for more information.

Thank you for reading.

Warm wishes,


Updated 2021


Weight Gain -  Cancer.Net

Weight Changes - American Cancer Society

Losing weight after breast cancer treatment  - Breast Cancer Now

The 2 day diet   - Michelle Harvie and Tony Howell (2013)

How to stay motivated    - NHS Choices

How to keep a healthy weight  - Cancer Research UK

Eating to lose weight after cancer treatment   -

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