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Tips for Treatment-Induced Weight Changes

CancerWise - April 2007

During cancer treatment, patients often unintentionally gain or lose weight, but being aware and taking proactive steps may help prevent or reduce the problem, dietitians say.

Weight loss – how to slow it down

Loss of appetite and subsequent weight loss are common side effects of cancer treatment, says Dena Reagan, a registered dietitian in M. D. Anderson’s Department of Clinical Nutrition. Chemotherapy, for example, can cause nausea, and radiation can change the way food tastes.

“If a patient has a rapid weight loss of more than two pounds per week that means he or she is not meeting protein needs and is losing more lean body mass, or muscle, than fat,” Reagan says. 

Dietitians recommend patients who have lost weight quickly add 250 to 500 calories, including protein sources, per day to help meet nutritional needs and slow weight loss.

“These calories can be in the form of between-meal snacks or liquids, such as milk and fruit juices,” Reagan says.

Weight gain – preventing and reducing it

Treatment-related weight gain can be caused by:

  • Some chemotherapies that reduce metabolic rates 
  • Steroids, which can increase appetite
  • Antidepressants, which can increase appetite 
  • Inactivity, which can be caused by fatigue

Patients at normal weight can help prevent weight gain by:

  • Increasing physical activity by 10 minutes a day
  • Eliminating:
    • Mindless snacking
    • Overeating at meals
    • Liquid sources of calories (juices, sodas)

Patients who are overweight or obese might talk to their doctors about gradual weight reduction during treatment, Reagan says.

The basic principle of losing weight is eat less, do more:

Reduce calories – A reduction of 250 calories a day equals weight loss of one half pound per week.

Exercise – Even 10 minutes a day can make a difference. Start by using stairs, parking farther away than usual, then add 10 to 15 minute walks three times a week. Patients can increase the duration of the walk or add a second walk later in the day. Exercise burns calories and increases heart and lung capacity and also fights fatigue.

Patients experiencing weight changes should ask their doctors about a referral to a dietitian who specializes in cancer. Weight management classes also may be available at individual cancer centers or hospitals.

– From staff reports


© 2015 The University of Texas MD Anderson Cancer Center