Decreased retronasal olfaction and taste perception in obesity are related to saliva biochemical and microbiota composition

• Published in: Food research international Vol. 167; p. 112660
• Main Authors: López-Dávalos, Paula Calvo, Requena, Teresa, Pozo-Bayón, M. Ángeles, Muñoz-González, Carolina
• Format: Journal Article
• Language: English
• Published: Canada Elsevier Ltd 01.05.2023
• Subjects: Adult; Aroma; Bacteria; Body mass index; Flavor perception; Food Preferences; Humans; Interindividual differences; Liking; Microbiota; Obesity - metabolism; Oral-brain axis; Personalized diets; Saliva - chemistry; Salivary microbiota; Smell; Taste Perception; Flavor perception; Body mass index; Salivary microbiota; Aroma; Oral-brain axis; Interindividual differences; Personalized diets; Liking
• ISSN: 0963-9969; 1873-7145
• DOI: 10.1016/j.foodres.2023.112660

[Display omitted] •People with obesity (OB) showed decreased retronasal and taste perception.•OB presented an impaired liking for specific flavor attributes.•Differences in salivary biochemical parameters between BMI groups were observed.•A relation between salivary bacterial community and obesity was found.•Specific salivary parameters associated with BMI were linked to flavor intensity. Understanding the individual factors that modulate flavor perception is a central issue for the development of personalized diets strategies to fight obesity. This study aimed to investigate differences in flavor perception between adults with normal weight and those with obesity, as well as some potential biological factors related to these differences. To do that, liking and flavor perception intensity were measured against retronasal olfactory (pineapple, butter, tropical and chocolate) and taste attributes (sweetness, umami and bitter) in 77 individuals grouped as normalweight or obese, according to their body mass index (BMI). Unstimulated saliva was collected from all participants and characterized in terms of salivary flow, total protein content, total antioxidant capacity, total esterase activity and bacterial composition through 16S rDNA amplicon sequencing. The results showed that participants displayed differences in flavor perception according to their BMI group. Thus, the group with obesity showed significant lower liking and intensity scores for low calorie related food aroma (pineapple and tropical), lower taste intensity scores for sweet and umami, and a higher acceptability for umami than the group with normal weight. Significant differences between BMI groups were observed for salivary biochemical variables and specific bacterial taxa, some of which were significantly correlated to flavor intensity. This work suggests for the first time the existence of an oral-brain axis that might contribute to the development or perpetuation of obesity, which opens new and interesting avenues of research.