Losing weight when you are not trying to is a common symptom in people with cancer.
Weight loss and cancer
Weight loss is common in people with cancer. It might be one of the reasons why you first go to the doctor.
There are several causes of weight loss and your doctor can treat many of these.
Losing weight is often associated with a loss of appetite. But this is not the only cause. For people with cancer, other causes are:
- a swollen tummy (abdomen)
- feeling and being sick (nausea and vomiting)
- difficulty swallowing
- feeling full because of a swollen (enlarged) liver
- a blocked bowel
- high levels of calcium in the blood
- not being able to absorb nutrients from food (malabsorption)
Some people may lose weight despite eating normally. This is called cachexia. With cachexia, your body may not be absorbing all the fat, protein and carbohydrate from the food you eat. And you may be burning up calories faster than normal.
People with cachexia lose muscle and often fat too. Scientists think that cancer releases chemicals into the blood. The chemicals contribute to the loss of fat and muscle.
Continuous weight loss can be worrying and a constant reminder of your illness. It can affect your quality of life and how you feel about yourself.
Weight loss can depend on cancer type
Weight loss can depend on the type of cancer you have.
About 60 out of 100 people with lung cancer (60%) have a loss of appetite and significant weight loss at the time of their diagnosis. In people with upper gastrointestinal cancer, this number is 80 out of 100 people (80%). Upper gastrointestinal cancers include:
- food pipe (oesophagus) cancer
- stomach cancer
- small bowel cancer
- pancreatic cancer
- liver cancer (including primary and secondary liver cancers, bile duct and gallbladder cancer)
When to worry about your weight
Your doctor will want to find out the cause if you lose, without dieting, more than 5% of your normal weight over 6 to 12 months.
Losing 5% of your normal weight may not seem like a lot. But if you continue to lose weight at this rate, it could become a severe problem.
Monitor your weight
- weigh yourself once a week at the same time, wearing the same clothes
- keep an eye on how tight or loose your clothes, watch or rings are if you don't have scales
Let your doctor or nurse know if you are worried about changes in your weight.