Chemotherapy is a common medical treatment for cancer, using strong drugs to destroy cancer cells. While effective, these treatments can cause side effects. A common concern for patients is how chemotherapy affects body weight. Individuals often experience either weight loss or weight gain, which can be distressing and affect overall well-being during treatment.
Factors Contributing to Weight Loss
Chemotherapy can lead to unintentional weight loss. Nausea and vomiting are frequent side effects that reduce a person’s desire and ability to eat, lowering caloric intake. Changes in appetite, including a general loss of hunger or feeling full quickly after eating small amounts, also contribute to decreased food consumption.
Taste and smell alterations are common, making once-enjoyable foods unappealing or causing a metallic taste in the mouth, discouraging eating. Mucositis, which causes painful sores and inflammation in the mouth and throat, can make chewing and swallowing difficult. Fatigue can diminish the energy needed to prepare meals or even to eat. Some chemotherapy drugs can also impair nutrient absorption, leading to malabsorption.
Factors Contributing to Weight Gain
Many individuals experience weight gain during chemotherapy. Steroid medications, frequently administered alongside chemotherapy to manage side effects, can increase appetite, promote fluid retention, and alter fat distribution. This fluid retention, or edema, can cause swelling, particularly in the limbs or face, contributing to an apparent increase in weight.
Reduced physical activity due to fatigue often leads to decreased calorie expenditure. Some people may also engage in emotional eating as a coping mechanism for stress or discomfort. Certain treatments can influence metabolism, potentially slowing it down and making it easier to gain weight, particularly with changes favoring fat gain over lean muscle mass.
Managing Weight Fluctuations
Managing weight fluctuations during chemotherapy involves tailored strategies for both weight loss and weight gain. For those experiencing weight loss, focusing on nutritional support is paramount. This includes consuming small, frequent meals throughout the day, opting for high-calorie and nutrient-dense foods, and utilizing liquid nutritional supplements if solid food intake is challenging. Strategies to manage nausea and vomiting, such as anti-nausea medications, can also help improve food intake.
To address weight gain, making healthy eating choices and practicing portion control are beneficial. Staying adequately hydrated with water and unsweetened beverages can help manage fluid retention. Incorporating light physical activity, if approved by the healthcare team, can assist with calorie expenditure and overall well-being. For steroid-induced weight gain, discussing dosage adjustments or alternative medications with the oncology team might be an option. Open and consistent communication with the oncology team and a registered dietitian is always advised to develop a personalized plan.
Individualized Response and Monitoring
The way an individual’s body responds to chemotherapy, including weight changes, varies greatly. Factors such as the specific type of cancer, the particular chemotherapy drugs administered, the dosage, the patient’s overall health status, and even genetic predispositions all play a role in determining these outcomes. For example, studies have shown that weight gain during chemotherapy is more commonly reported in women with breast cancer, with average gains ranging from 1.4 to 5.0 kg.
Consistent weight monitoring by both the patient and their healthcare team is therefore very important. Patients should report any sudden or significant weight changes, whether a loss of more than 3 pounds in a week or a gain of 5 pounds or more in a week, to their doctor or nurse without delay. Receiving personalized guidance from medical professionals, including dietitians, ensures that any weight concerns are addressed appropriately, supporting overall health throughout the treatment journey.