Assessing Tyg Index and Dietary Intake During Chemotherapy in Breast Cancer Patients

Breast cancer is the most common cancer in Indonesian women. Chemotherapy has side effects that affect the patients’ dietary intake. The triglyceride glucose index (Tyg Index) is a marker for assessing insulin resistance in breast cancer. Insulin resistance is related to insulin receptors’ activation. This study aims to assess TyG index and dietary intake during chemotherapy in breast cancer patients. This observational, prospective cohort study conducted with 37 adult women with breast cancer at Hasanuddin University Hospital and Wahidin Sudirohusodo Hospital Makassar from September 2024 to March 2025. Dietary intake was assessed thrice: a day before chemotherapy, 5th and 18th day of chemotherapy. Data on macronutrient were used for assessing dietary intake. The intake of energy (kcal), protein (gram), carbohydrate (gram), and lipid (gram) was increased after chemotherapy (1182.4 ± 252.2 to 1332.8 ± 291.3; 54.1 ± 16,2 to 59.7; 184.9 ± 43.1 to 188.2 ± 47.7; 23.3 ± 8.4 to 25.1 ± 9.7). All of macronutrients decreased in 5th days of chemotherapy but increased in 18th days of chemotherapy. Our study found that TyG index had a weak negative relationship with the dietary intake. Increased dietary intake during chemotherapy of breast cancer patient associated with lower TyG index after chemoterapy. This study showed that better dietary intake contributes to a significant decline in insulin resistance among individuals diagnosed with breast cancer.