Weight gain

Some people find they don’t lose weight during treatment. They may even gain weight. This is particularly true for people with breast, prostate, or ovarian cancer who are taking certain medicines or getting hormone therapy or chemotherapy.

If you notice you’re gaining weight, tell your cancer care team so you can find out what may be causing this change. Sometimes you gain weight because certain cancer-fighting drugs cause your body to hold on to extra fluid. If this is the case, your doctor may ask you to talk with a registered dietitian for help with limiting the amount of salt you eat. This is important because salt might cause your body to hold extra water.

Many women with breast cancer gain weight during treatment. Because of this, many of the recommendations for breast cancer patients include a reduced-calorie diet much like those suggested for patients after cancer treatment has been completed. If you have any questions, talk to your cancer care team about the best diet for you.

Weight gain may also be the result of increased food intake and decreased physical activity. Some people find it helps their nausea to have something in their stomachs, so they eat more. Other people eat more when they’re stressed or worried.

If you want to stop gaining weight, here are some tips that can help:

What to do

  • Ask your cancer care team for a referral to a registered dietitian to help you get your nutrition needs met without gaining weight.
  • Try to walk daily if you can and if it’s OK with your doctor. Talk with your cancer care team about referral to a physical therapist to help you safely increase activity levels.
  • Limit food portion sizes, especially with high-calorie foods.
  • Choose fish, poultry, or beans and peas instead of red meat. If you eat red meat, choose only lean cuts and eat smaller portions.
  • Choose whole-grain breads, pasta, and cereals (such as barley and oats) instead of breads, cereals, and pasta made from refined grains, and brown rice instead of white rice.
  • Limit your intake of refined carbohydrate foods, including pastries, candy, sugar-sweetened breakfast cereals, and other high-sugar foods.
  • Read food labels to become more aware of portion sizes and calories. Be aware that “low-fat” or “non-fat” doesn’t always mean “low-calorie.”
  • Choose vegetables, whole fruit, and other low-calorie foods instead of calorie-dense foods such as french fries, potato and other chips, ice cream, donuts, and other sweets.
  • Choose low-fat dairy products (skim or 1% milk, light yogurt, reduced fat cheese). Cut back on added butter, mayonnaise, and other fats.
  • Choose low-fat and low-calorie cooking methods (such as broiling and steaming).
  • Limit high-calorie snacks between meals.
  • Limit or avoid intake of sugar-sweetened beverages such as soft drinks, sports drinks, and fruit-flavored drinks.
  • When you eat away from home, be especially mindful to choose food low in calories, fat, and added sugar, and avoid large portion sizes.
  • Include activities that will help relieve your stress. .

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 Medical Review: July 15, 2015 Last Revised: July 15, 2015

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