Weight changes  

Many people experience changes to their weight following a cancer diagnosis. This may involve either weight gain or weight loss. 

Weight loss can happen because of the cancer itself, or as a result of treatment side effects. These may include changes in taste, reduced appetite, nausea, diarrhoea or constipation.  

You can find more information on maintaining your weight during cancer treatment on our Nutrition and Healthy Eating pages.  

Healthy eating is not always possible or appropriate for everyone during cancer treatment. Some cancers and their treatments can make eating and drinking more difficult, and you may need to change the types of food you eat.  

Some people may continue to lose weight even when they are eating well and might need extra support. This information will provide some advice and guidance on when you might need additional help. If you have lost weight recently, have noticed a drop in your appetite or are struggling to eat and drink, please ask your team to refer you to the dietitian.   

Some cancer treatments can also lead to weight gain, and this is a very common experience. Changes such as moving less because of fatigue, eating for comfort during a stressful time, or going through menopause‑type symptoms can all contribute to gaining weight.  

If you are finding weight gain difficult or worrying, please speak with your oncology team. They can offer guidance and, if needed, refer you to a dietitian who specialises in supporting people during and after cancer treatment. 

You may also find it helpful to look at our Nutrition and Healthy Eating pages, where you’ll find practical tips, recipes, and guidance on eating well during recovery 

Changes in weight can also affect how you feel about your body. Many people notice changes in how they look or how comfortable they feel in their own skin during and after treatment. If you would like more support with this, please see the Body Image pages for information, reassurance and guidance.