Weight gain and cancer

Many people had a healthy lifestyle before their cancer diagnosis and treatment. But sometimes it can be a challenge to maintain this. People don’t usually expect to gain weight during cancer treatment.

But some treatments, side effects or even lifestyle changes can cause you to put on weight:

  • Treatments – some chemotherapy drugs, steroids and hormonal therapies can cause weight gain.
  • Tiredness due to the cancer or treatment – this can make you less physically active than usual, which may cause you to gain weight.
  • Depression – for some people, natural feelings of sadness or worry about the cancer can develop into depression. Eating more and gaining weight may be symptoms of this.
  • Stopping smoking – this is the healthiest decision anyone who smokes can make. But it can cause weight gain at first. You’ll be much healthier after quitting though, and you can gradually lose the extra weight.
  • Comfort eating – some people turn to food for comfort when life is stressful, which can lead to weight gain.
  • People close to us may offer food as a way of showing that they care and want to be helpful. And it can be difficult to refuse such a kind offer.

Don’t be too hard on yourself if you find you’ve put on weight. Sometimes, knowing why it’s happened can help you think of ways to manage it.

After treatment, most people need time to recover. But as you gradually get better, you may find that you’re ready to make some changes.

If you think you’ve gained weight because you’re depressed, talk to your GP or nurse. There are effective treatments for depression, such as counselling and antidepressants.

If you’re having hormonal therapy as part of your treatment, it’s very important not to stop taking this, even if you think it’s causing weight gain. Talk to your cancer doctor or nurse if you’re concerned about this. Eating healthily and being more physically active will help you manage your weight.

Talk to your doctor and nurse

Before trying to lose weight, it’s important to speak to your GP, cancer doctor or nurse. They can talk to you about the right approach for you, based on the cancer you have and its treatment.

They’ll also take into account your weight before diagnosis and any other medical conditions you may have.

Your doctor or nurse will measure your body mass index (BMI) and blood pressure, and may take a blood test.

They might also suggest you see other health professionals for advice, such as a dietitian, physiotherapist or specialist nurse. They can also give you information about where you can get help and support locally.

Back to Managing weight gain

Managing your diet

Knowing about the different food types can help you manage your diet, reduce your calorie intake and lose weight.

Tips for losing weight

Changing your eating habits, reducing portion sizes, and taking care when eating out can all help you manage your weight

Healthy eating ideas

We have put together some ideas for a week’s worth of healthy meals and snacks