Signs of cancer: Unexplained weight change
Unexplained changes in weight are one of the most common signs of cancer in young people. Use this page to find out more about what to do if you notice this.
- This can be weight gain or weight loss, when you haven’t changed your lifestyle
- You know your body better than anyone else, so if you notice changes that are worrying you, you should get them checked out
- A change in your weight doesn’t mean you definitely have cancer, but if you notice anything unusual, make an appointment with your GP
- Below you’ll find more information about how you can best explain your symptoms to your GP
When should I go to the GP?
If you’ve experienced an unexplained change to your weight, you should go to see your GP. This could be either weight gain or weight loss, when you haven’t been trying to gain or lose weight and you haven’t changed your lifestyle.
Lifestyle changes might include changing your diet (eating more or less, or changing the types of food you eat) or if you’ve started exercising lots more or less.
If you haven’t made any changes and are still experiencing a change to your weight, then you should speak to your GP as this could be a sign of cancer. It doesn’t mean you definitely have cancer, but if you notice anything unusual you should make an appointment with your GP.
What should I tell the GP about my symptoms?
It’s important you tell your GP as much as you can about any changes to your weight that you’ve experienced. It might be hard to remember exactly what you noticed and when, but we’ve put together a list of questions you can answer to make sure you give your GP as much info as possible.
Not all GP appointments will be in person, you might speak to your GP on the phone or via video call first. Even if you’re not speaking to your GP in person it’s still really important to give as much information as possible.
You can copy and paste this list below into the notes app on your phone or a Word document, or you can write down your notes in a notebook and take it to the appointment with you:
- Have you lost weight or gained weight?
- How much weight have you lost/gained? (If you’re not sure of the exact amount that’s fine, but try and explain how you’ve noticed the change in your weight on your body.)
- When did you first notice this?
- Have you had any recent lifestyle changes? (Changed your diet or started exercising more or less?)
- How is this weight change making you feel?
- Are there any other changes to your body that you’ve noticed?
What could it be?
Unexplained weight change could be a sign of lots of different types of cancer. Using the pages below you can find out more about the other symptoms associated with each of these types of cancer.
Again, it’s important to remember that having any of these symptoms doesn’t mean you definitely have cancer, but if you notice anything unusual you should book an appointment to see your GP.
Most common signs of cancer in young people
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The Patient Information Forum is the UK membership organisation and network for people working in health information and support. The PIF TICK is the UK-wide Quality Mark for Health Information.