Fatigue is feeling very tired all the time. It doesn’t get better when you rest. It’s a common problem for people with cancer and those getting cancer treatment. If you’re feeling tired or lack energy, talk to your cancer care team.

Fatigue can have many causes, including cancer treatments, not eating enough, lack of sleep, depression, low blood counts, and some medicines. When the cause of the fatigue is medical, your doctor may be able to treat the cause to help you feel better. Along with treatment, there are many nutrition steps you can take and other things you can try to help you cope with fatigue.

What to do

  • Talk to your cancer care team about your fatigue. If there’s a medical cause, there may be treatment for it. They can help you figure out self-care measures that may help with the fatigue, too.
  • Try to prioritize your activities. Do the most important ones when you have the most energy.
  • Take short walks or get regular exercise, if you can. More and more research tells us that being moderately active can help decrease cancer-related fatigue.
  • Drink plenty of fluids. Dehydration can make fatigue worse. Be sure to get at least 8 cups of fluid each day. If you are losing weight, be sure to include some fluids that have calories, like juices or milk.
  • Make sure you get enough rest. Take 3 or 4 short naps or rest breaks during the day instead of 1 long rest. Plan your day to include rest breaks, and make rest time special with a good book in a comfortable chair or a favorite movie with a friend. Try to balance rest and activity so that it doesn’t interfere with nighttime sleep.
  • Try easier or shorter versions of your usual activities. Don’t push yourself to do more than you can manage.
  • Ask for a referral to a dietitian who can work with you to choose the best diet for you.
  • Try eating some protein, fat, and fiber with each meal and snack to help keep blood sugar levels more stable. This will give you a more sustained feeling of energy from the food you eat. For instance, instead of eating 2 pieces of fruit, try eating 1 piece plus a small handful of walnuts, almonds, peanuts, or other nuts. Or try fruit with cottage cheese.
  • Be sure to meet your basic calorie needs. (See “Tips to get more calories and protein” in the “ Once treatment starts” section.)
  • Do not take large amounts of vitamins or minerals without first talking with your cancer care team. Some dietary supplements can interfere with your cancer treatment, and large doses of some supplements can have harmful effects.
  • Stress can make fatigue worse. Ask your cancer care team about stress management.

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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