Weight changes during treatment for cancer are common. There are a number of causes for weight loss including:
- Eating less due to nausea or poor appetite
- Diarrhea
- Vomiting
- Dehydration
(You can learn more about each of these in their related sections.)
Causes for gaining weight include:
- Less activity
- Eating more
- Retaining water (See the section called "Swelling.")
- Certain medicines
Weight changes of more than 5 pounds in a week should be reported to your doctor. A decrease in weight over time may affect the patient's ability to function, and make them weak and unable to perform daily activities. Quick weight loss is often a sign of dehydration. An increase in weight over time may suggest a serious health condition, such as diabetes or high blood pressure. You may be able to tell if you gain or lose 5 pounds in a week by the way you feel or the way your clothes fit, or you can weigh yourself on a scale once a week or so.
What to look for
- Weight loss of 5 pounds or more in a week or less
- Dry skin
- Fatigue, weakness
- Feeling very thirsty
- Dizziness
- Clothes or rings are too big
- Weight gain of 5 pounds or more in a week or less
- Swollen ankles
- Shortness of breath
- Feeling puffy or bloated
- Tight shoes, clothes, or rings
OR
What the patient can do
If you have lost weight:
- Drink extra high-protein and high-calorie fluids between meals.
- Be sure to drink enough water or other liquids that have no caffeine.
- Eat high-protein foods. You may also try liquid food supplements.
- Ask your doctor or nurse to arrange a meeting with a dietitian.
If you have gained weight:
- Talk with your doctor or nurse about limiting fluid if your ankles are swollen.
- Limit your salt intake.
- Limit high-calorie foods.
- Ask your doctor or nurse to arrange a meeting with a dietitian.
What caregivers can do
- Weigh the patient at the same time every day and write it down along with the date. In the morning, before breakfast, is a good time.
- Talk to the doctor if the patient’s weight loss or weight gain concerns you.
- Watch the patient for other symptoms.
Call the doctor if the patient:
- Loses or gains more than 5 pounds in a week
- Has shortness of breath
- Feels dizzy or becomes confused
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