Timely insight on cancer topics from the experts of the American Cancer Society

"Well, I could stand to lose some weight." As a cancer dietitian, I have heard this more times than I can count in the past 10 years. But most people are surprised when I explain to them that losing weight during their treatment may not be the best time. While getting to a healthy weight over the long run can be a healthy thing to do, it can actually be harmful before and during cancer treatment.

For some people with cancer, keeping weight stable can feel like an uphill battle since there are many factors that can contribute to weight loss even before patients are diagnosed. For instance, the cancer itself may produce chemicals called "cytokines" that can give you less of an appetite or cause nausea. Or the location of a tumor may place pressure on the digestive tract, making you fill up on food easily or have a hard time swallowing. After receiving a diagnosis, anxiety about the diagnosis and upcoming treatment can take away appetite. Then once treatment begins, side effects such as nausea, diarrhea, taste changes, and sore throat can change what and how much people are eating.

Weight loss can affect recovery

But weight loss before and during treatment can reduce the extra energy and nutrients your body stores and impact recovery in many ways. Surgical incisions need protein to create the new tissues needed to heal them. Chemotherapy kills off rapidly dividing cells, such as the lining of the digestive tract and hair, that need adequate energy (in the form of calories) and protein to be replaced. Poor nutrition and weight loss during this time make it harder for this healing and recovery to happen by forcing your body to dip into lean muscle mass (in addition to fat stores) to get the building blocks it needs to make new tissue.

When your body is forced to take extra protein and energy from your lean body mass, the impact is greater than just healing more slowly. It also affects things like stamina and energy, so standing at the stove to cook a meal or getting up to use the restroom in the middle of the night takes more effort than usual.

And of course, your medical team is concerned about the overall impact this may have on your treatment regimen. If you've lost weight and don't have the extra energy and nutrients you need to create new cells to help your immune system fight infection, your chemotherapy, which is very carefully timed to destroy cancer cells when they're at their most vulnerable, might be delayed.. And a lot of weight loss can cause breaks in your radiation treatment as well: if weight loss is happening because of pain with eating or diarrhea from treatment, your healthcare team may become concerned about your quality of life and order a pause in your treatment.

When to worry

So how much weight loss is too much? At what point do we start to worry? Most practices will tell you to lose no more than 1-2 pounds per week, but that number means far more to a 105-pound woman with 6 months of treatment ahead of her than it does to a 250-pound man with 5 weeks of treatment. Some treatment centers may have their own standards, especially for diagnoses like head and neck cancers, pancreatic cancer, or gastrointestinal cancers, when patients are more likely to lose weight rapidly.

Losing 1%-2% of your body weight in a week or 5% in a month may be enough to worry your health care team. That would be the equivalent of a 150-pound person losing 1.5 to 3 pounds in a week, and 7.5 pounds in a month. Some facilities look for weight loss over a longer time period, generally a 10% loss over 3 months. Overall, your healthcare team is watching for trends. Keep in mind that weight differences after chemotherapy are common, often up to 5 pounds, but it is not a concern as long as you get close to your starting weight before the next treatment.

Ideas for weight gain

So what can you do to keep your weight stable during treatment? First, it's important to understand that getting good nutrition isn't just for helping you stick to your treatment regimen. You also need strength to maintain independence and keep some control in your own life. Often cancer patients feel like they have few choices when it comes to their treatment program, but taking control over what you eat can give you some of that power back and make you feel like an active participant in your care.

I encourage patients to start by adding approximately 250 calories a day. If liquids are easier to tolerate than solids, this could be as simple as adding a glass of milk to meals. If a heavy treatment schedule gets in the way of mealtimes, it could mean eating a pack of peanut butter crackers or a serving of trail mix in the car on the way to a doctor's appointment. If nothing tastes good, your throat hurts, or you have mouth sores, it could even mean having a scoop of premium ice cream as a bedtime snack.

After a week or 2, we reevaluate how the strategy works. If you continue losing weight, we may need to try a more aggressive approach. Eating every 2 hours, adding more frequent snacks, or boosting the calories in the foods you already enjoy may help. We can discuss what may and may not be working to manage your side effects. It may even be time to talk with your health care team about an appetite stimulant.

Ask your cancer center if they have a dietitian you can meet with to develop a plan for your specific needs. If you are not currently in treatment or if your healthcare provider does not have a dietitian, contact our American Cancer Society National Cancer Information Center to see if there are any free programs in your area.

To learn more about the importance of good nutrition during treatment and get some delicious recipes that are intended to help cancer patients keep and gain weight, see our information on Nutrition for People with Cancer.

I was wondering if purchasing some decent weight gain might help for cancer patients. There are weight gainers on the market which contain around 2,500 calories in one serving and are packed full of vital nutrients such as protein and vitamins. I beleive this would be beneficial in an individual with cancer as it provides them with many antioxidants to keep the body healthy. This and the fact that it is liquid is why i would recommend it

My friend is going to chemo and has lost about 15 pounds in three months. She will still get chemo till the beginning of May. Nothing tastes good and she has sores in her mouth. She has colon Rectal cancer and her Dr. removed it all. I am worry with the loss of weight and mussel....She can't drink cold as it bothers her. Her Dr. is saying possibilty of a feeding tube, but she ( my friend) doesn't want another surgery. I want to help but don't know what to do. Can you help me?

Hi, DaleAnne, I'm so sorry to hear about your friend. That is a very difficult situation. I'd recommend you call our National Cancer Information Center, anytime of the day or night, at 1-800-227-2345. Also, be sure to check out this link, which may help too. Best wishes to your friend!www.cancer.org/.../index

I had my last chemo over 4 years ago.I lost 40 pounds during treatment,no one was very concerned.When I regained my appetite,I ate,but was still too weak to do much.I have gained fat and lost muscle.I am desperate for someone to tell me what to do to regain my strength.It seems once chemo is over,you are on your own and especially a few years out of treatment.I try to exercise but end up irritating an old back injury.I live in a very rural area with few options.