Abstract Background: Dysgeusia is a frequent side effect in breast cancer patients undergoing adjuvant chemotherapy. The effect of dysgeusia on changes in diet and patient weight has been poorly investigated. We evaluated prospectively dysgeusia in a consecutive series of early breast cancer patients (EBCP) with the aim to explore its impact on food selection and weight changes. Patients and methods: From May 2014 to April 2017, 130 consecutive EBCP were enrolled at the Oncology and Breast Units at Spedali Civili in Brescia. Dysgeusia was categorized as present or absent, changes in types and frequencies of food consumptions during chemotherapy were assessed by a specific questionnaire and photography atlas. Evaluations were performed at baseline, after 3 cycles, at the end of chemotherapy plan and during follow-up. Results: all 130 pts were evaluable. Median age was 53 years (range 26-76), median weight 64 Kg (range 45-115), median BMI 23,86 Kg/m2 (range 17,01-35,49), 73 pts (56%) performed physical activity, 57 pts (44%) were abstemious, 22 pts (17%) received neoadjuvant and 108 pts (83%) adjuvant chemotherapy, 25 pts (19%) were treated with antracycline based schemes, 83 (64%) with antracycline and taxane plus or minus trastuzumab, and 22 pts (17%) other regimens. Seventy-three per cent of pts developed dysgeusia during chemotherapy (p=< 0.001), and in 19% this side effect persisted three months after chemotherapy. Dysgeusia was associated with the length of chemotherapy treatment and taxane use. A statistically significant increase of taste alteration was reported for all metallic, sweet, bitter, salted and acid taste (p<0.001). Dysgeusia was more frequent in pts reporting meteorism and fatigue and in pts without oral mucositis (p=0.002). Dysgeusia correlated with a lower intake of bread, cheese, fat salami, butter and wine and a high intake of biscuits and cakes. However, no correlation was observed with weight and BMI changes. Conclusion: Dysgeusia was frequent in EBCP undergoing adjuvant chemotherapy. It directly correlated with fatigue and meteorism and inversely correlated with mucositis. This adverse event had no impact on weight and BMI but significantly influenced food intake with a preference of glucose containing instead of fat containing foods. Acknowledgments: a thank you to Beretta foundation for the costant support to Breast Unit and Oncology Department. Citation Format: Pedersini R, Zanini A, Romelli M, Coccoli V, Guerra M, Bosio S, Schivardi G, Rodella F, Vassalli L, Amoroso V, Claps M, Simoncini EL, Berruti A. Dysgeusia, weight and eating habits changes in breast cancer patients undergoing chemotherapy: A prospective cohort study [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-11-16.