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Symptom guide

Unintentional weight loss

Find out what can cause unintentional weight loss and when to get medical help.

About this information

This NHS content is written for people in England. Services, contact routes and treatment arrangements may differ in other countries.

Causes of unintentional weight loss

Unintentional weight loss can have many different causes.

It might be caused by a stressful event like a divorce, losing a job, or the death of a loved one. It can also be caused by a health condition or a combination of things.

Some causes of unintentional weight loss include:

Sometimes weight loss and loss of appetite can be caused by cancer. It's important to get it checked if you're losing weight without trying.

See a GP if:

  • you keep losing weight without changing your diet or exercise routine

It's important to see a GP as soon as possible if you have weight loss and other symptoms. The earlier the cause is found, the sooner it can be treated.

Treatment for unintentional weight loss

Treatment for unintentional weight loss depends on what's causing it.

A GP will ask about your health and may arrange some tests or scans.

Depending on the possible cause, they may:

  • advise you about things you can do to help, such as ways to reduce stress
  • recommend treatment for any condition that's causing you to lose weight
  • refer you to a specialist

Unintentional weight loss

Causes

Unintentional weight loss

Medical treatments

Many things can cause unintentional weight loss. Common causes are stress and digestion problems. Sometimes it can be something serious like cancer.

Treatment for unintentional weight loss depends on the cause. A GP might be able to treat you or refer you to a specialist if needed.

Content supplied by the NHS website

Content supplied by the NHS website, refreshed 19 August 2026. View the original NHS article ↗

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