Weight Gain

Most people lose weight during cancer treatment. But some people put on weight. Either way, it is very important to maintain good nutrition during treatment. Eating well and drinking plenty of fluids can help you cope with the side effects of treatment and will help your body heal after treatment.

People sometimes gain weight during treatment for cancer. Gaining a little weight is OK, but gaining a lot can affect your health.

Weight Gain Overview

Weight gain may happen as a side effect of treatment. For example, the use of steroid medications to treat cancer may cause an increase in your fatty tissue. Hormone therapies also may increase fat, as well as decrease muscle and lower your metabolism (burn fewer calories).

Chemotherapy sometimes causes the body to build up fluid (called edema). It also may cause fatigue, which could lower your metabolism and make you feel too tired to stay physically active. Chemotherapy also may lead to increased hunger for high-fat foods or intense cravings for food.

It may be possible to control weight gain by relieving these or other side effects of treatment.

Eat Well During Treatment

It can be hard to choose healthy foods during cancer treatment, but the following tips can make it easier. The American Cancer Society has information and tips on eating well. You also may need to drink extra fluid to protect your bladder and kidneys during your treatment.

Get Nutrition Counseling

  • Working with a professional licensed nutritionist or registered dietician can help you control weight gain during treatment and offer good advice specific to you.
  • Ask your doctor to refer you to a nutritionist or dietician. 

Focus on Healthy Eating

  • Try eating more plant-based foods, like beans and peas, instead of meat.
  • Eat lots of fruits and vegetables including citrus fruits and dark-green and deep-yellow vegetables.
  • Don’t eat too many high-fat foods, especially those from animal sources.
  • Try not to eat too many salty, smoked, or pickled foods.

Choose Healthy Snacks

Healthy snacks such as fruit, nuts, or granola can help you maintain a healthy weight during your cancer treatment. Get some quick-and-easy snack ideas.

Stock Your Kitchen with Healthy Foods

  • Keeping your kitchen full of healthy foods can be a difficult task if you don’t know what to buy.
  • Use this shopping list from the American Cancer Society to help make grocery shopping easy. The list includes items like:
    • Beans, rice, pasta, and other grains.
    • Vegetables and fruits.
    • Meats like chicken breast, ground turkey breast, and lean cuts of meat.
    • Fish, including red snapper, salmon, cod, flounder, and sole.

Get Support

For more detailed information on support options, visit Get Support.

Talk to Your Health Care Team

Your health care team needs to know how you’re doing. Be sure to tell them about any changes you notice.

Talk to Family and Friends

Your loved ones want to support you. They can help with activities like housework, running errands, and getting to appointments. Be as specific as possible about the kind of help you need.

Find Peer Support

Talk About Your Concerns

Peer groups offer a welcoming environment to share your feelings and experiences with people who are going through the same things. Use the American Cancer Society’s Resource Search to find a peer group in your area or call the American Cancer Society at 1-800-227-2345 for personalized assistance.

Visit the Cancer Survivors Network Online

The Cancer Survivors Network is an online community with more than 40 discussion boards where cancer survivors share their cancer-related experiences, support one another, and exchange practical tips.

NCI Cancer Information Service


Speak to a National Cancer Institute health information specialist by calling 1-800-4-Cancer.


The National Cancer Institute offers live, online assistance through its LiveHelp service.

ACS National Cancer Information Center

Get Tips

Get information and tips from a cancer information specialist at the American Cancer Society by calling 1-800-227-2345. Lines are open 24 hours a day, 7 days a week.


The American Cancer Society offers live, online assistance 24 hours a day, 7 days a week. Select the Live Chat option from any page on cancer.org.

Learn More About Weight Gain

The American Cancer Society has additional resources to help you, including nutrition and physical activity during and after cancer treatment and weight gain.