Metabolic Changes After A Breast Cancer Diagnosis


Many women gain weight or increase in body fat percentage after a breast cancer diagnosis. These metabolic changes increase the risk of recurrence and other complications like diabetes and heart disease. Understanding why this happens can help you make lifestyle changes to support your health. Continue reading to learn about various factors that can contribute to weight gain during and after breast cancer treatment, and what you can do to address them.

How does breast cancer treatment cause weight gain?

Breast cancer treatments themselves may contribute to weight gain and changes in body composition. Women who receive chemotherapy have an increased risk of weight gain and metabolic dysfunction. Studies on weight gain from hormone-blocking medications like tamoxifen and aromatase inhibitors are mixed. However, a recent study found that women who have more side effects from these medications are at an increased risk of weight gain. Joint pain from aromatase inhibitors can make exercise more difficult. Many cancer treatments are believed to negatively impact the gut microbiome which can also increase weight gain.

How treatment side effects can impact your weight

Side effects during treatment can impact weight gain and metabolic changes, and therefore need to be addressed more fully. Fatigue makes participating in physical activities more challenging. Sleep-disrupting hot flashes and insomnia are common in breast cancer survivors. Poor sleep can impact hormones like leptin and ghrelin, which impact food cravings and hunger cues. Sleep issues and chronic stress from a cancer diagnosis can also increase cortisol levels. Cortisol can increase insulin, decrease metabolism, and increase the storage of visceral fat in the belly.

What can you do about these changes?

Breast cancer survivors need to understand the risk of these metabolic changes for their health. They also need support to adopt a proactive approach and maintain their overall well-being. Here are a few practical tips to help you manage weight gain and a healthier lifestyle throughout survivorship.