Cancer Treatment Chemotherapy Understanding Weight Loss Caused by Chemotherapy Despite what you've heard, weight loss is not a given By Lisa Fayed Lisa Fayed Lisa Fayed is a freelance medical writer, cancer educator and patient advocate. Learn about our editorial process Updated on January 11, 2022 Medically reviewed Verywell Health articles are reviewed by board-certified physicians and healthcare professionals. These medical reviewers confirm the content is thorough and accurate, reflecting the latest evidence-based research. Content is reviewed before publication and upon substantial updates. Learn more. by Cristian Zanartu, MD Medically reviewed by Cristian Zanartu, MD Twitter Cristian Zanartu, MD, is a licensed board-certified internist who has worked for over five years in pain and palliative medicine. Learn about our Medical Expert Board Print Weight loss may seem like the silver lining of chemotherapy, but the truth is that not everyone on treatment loses weight. It's one of the false impressions we've gotten from TV and film: where the character with cancer almost always ends up looking emaciated and frail. That is not to say that weight loss doesn't occur; it is simply not a given. Wavebreakmedia / Getty Images In the end, everyone responds differently to chemotherapy, and there are many factors that play a role in how treatment will affect your weight. Sure, there are some who will lose weight, but there are those who gain, as well. Understanding your nutritional needs and the possible side effects of treatment are the first steps to ensuring you maintain your ideal weight during the course of chemotherapy. Factors Contributing to Weight Loss When people lose weight during cancer treatment, it is most often due to an inability to maintain good nutrition. Chemotherapy can sometimes cause nausea and a general loss of appetite, while vomiting and diarrhea can greatly impact your ability to retain nutrients from the foods you eat. At times, foods can taste and smell very different – even foul – as a result of cancer treatment. For this reason, alone, many specialists recommend avoiding your favorite foods as any changes in taste or smell will be more profoundly perceived, creating an aversion to them even after treatment is complete. Mouth sores can also be a side effect of chemotherapy. Having them on your gums, throat, tongue, or inner cheek can make eating certain foods extremely difficult, exacerbating the pain you may already be feeling. Spicy, salty, or sour foods are especially problematic. Maintaining Weight During Chemotherapy One of the mains health goals you should strive for during chemotherapy is to keep your weight stable. If you are overweight, now is not the time to start losing. You can, however, focus having a more healthy diet, which you can carry over post-treatment to reach your ideal weight. If your healthcare provider feels you are up to it, work together to create an exercise plan to meet your fitness needs. Walking, yoga, and other forms of exercise are not only ideal ways to keep fit, but they can also help relieve stress, elevate your mood, and even reduce fatigue. Working with a dietitian experienced in cancer therapy can be extremely beneficial. A professional trained in the nutritional needs of a person with cancer will be more able to formulate, monitor, and adjust your diet as you move through treatment. Most cancer centers have a nutritionist on staff or can refer to a certified professional in your area. A Word From Verywell It almost goes without saying that good nutrition is essential during chemotherapy. If your caloric intake is too low, it can lead to weight loss while lowering your ability to cope physically and mentally with your treatment. Poor nutrition can also lead to a drop in your blood cell counts, resulting in anemia, neutropenia, or thrombocytopenia. This will not only make you feel tired and fatigued, but it can also lead to the discontinuation of therapy until such time as your levels are restored. In addition to good nutrition, exercise of any sort can be beneficial if approached wisely and under the supervision of a medical professional. Even a little outdoor activity (such as gardening) can prevent the loss of lean muscle mass key to maintaining strength and mobility. Overexertion, on the other hand, is not advised as it can not only wear you out but cause inflammation that can worsen any side effects you may be experiencing. Good planning, a balanced diet, and a moderate approach to fitness are three things you need to ensure you meet your health goals during the course of chemotherapy. Was this page helpful? Thanks for your feedback! Limiting processed foods and red meats can help ward off cancer risk. These recipes focus on antioxidant-rich foods to better protect you and your loved ones. Sign up and get your guide! Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit 3 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Sánchez-lara K, Ugalde-morales E, Motola-kuba D, Green D. Gastrointestinal symptoms and weight loss in cancer patients receiving chemotherapy. Br J Nutr. 2013;109(5):894-7. doi:10.1017/s0007114512002073 National Cancer Institute. Eating Hints: Before, during, and after Cancer Treatment Chaveli-lópez B, Bagán-sebastián JV. Treatment of oral mucositis due to chemotherapy. J Clin Exp Dent. 2016;8(2):e201-9. doi:10.4317/jced.52917