Unwanted weight gain

Some children do not lose weight during treatment. They may even gain weight. This is often true for those taking certain medicines or some types of chemotherapy. You may find that your child craves unusual foods and may be hungry at unusual times, or even all the time.

If you notice your child is gaining weight, tell your doctor so you can find out what may be causing it. Sometimes, he may gain weight because certain cancer-fighting drugs cause his body to retain fluid. If this is the case, the doctor may ask you to talk with a registered dietitian for help limiting the amount of salt he eats. (Salt causes the body to hold extra water.) The doctor may also want to give your child a diuretic or “water pill.” This is a medicine that causes the body to get rid of excess fluid and it will make them have to go to the bathroom a lot.

Increased appetite, eating more, and decreased physical activity can also cause weight gain. If this is the case and you want to help your child stop gaining too much weight, here are some tips that can help:

  • Try daily walks with your child if he is able to and if it’s OK with his doctor.
  • Limit the size of food portions.
  • Include plant-based foods like vegetables, whole grains, fruits, beans, and peas in your child’s diet.
  • Choose lean meats (lean beef or pork trimmed of fat, chicken without skin) and low-fat dairy products (skim or 1% milk, light yogurt, reduced fat cheese).
  • Cut back on added butter, mayonnaise, sweets, and other extras.
  • Choose low-fat and low-calorie cooking methods (like broiling and steaming).
  • Limit high-calorie snacks between meals.
  • Talk with a registered dietitian for other ideas.

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Last Revised: June 30, 2014

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