Flavor identification inversely correlates with Body Mass Index (BMI)

Background and aims Dietary choices are influenced by several factors, including physiological, social or genetic factors. Among these, flavor is the most important determinant modulating food preferences. Aim of the present study was to assess flavor identification abilities in patients with obesity (Ob) in comparison with matched normal weight (NW) and over-weight (OW) subjects using a specific and validated chemosensory test. Methods and results The flavor test was administered to 140 Ob patients recruited in the obesity outpatient Unit at the Federico II University hospital and to the same number of NW and OW subjects matched by sex, age and smoking habit. Flavor score (FS) inversely correlated with BMI. Median [Q1; Q3] FS was significantly higher in NW (14.5 [12; 16]) than in Ob (13 [11; 15], p<0.001) and not significantly different from OW (15 [12; 16]) individuals. FS was also higher in OW than in Ob subjects (p<0.005). When separated according to age quartiles, the BMI-related differences in FS were still significant in younger quartiles, while they were abolished in the older. Conclusions BMI is a critical factor modulating flavor identification, particularly in young subjects. Further investigations are needed to explore the precise mechanism and the causal relationship between body weight and olfactory dysfunctions.