In young adult males, bitterness perception is associated with excess body mass and metabolic dysregulation

Bitterness perception requires activation of the taste-receptor cells (TRCs) in the lingual papillae. The TAS2R38 specialist receptor (T2R family) is activated by thiol-urea chemicals, where 3 haplotype combinations are highly related to bitterness perception. Tasters (PAV/PAV) and non-tasters (AVI/AVI) represent the homozygous phenotypes, while the heterozygous combinations form the moderate tasters, who comprise approximately half of the population.

We determined the bitterness perception phenotype of 153 young adults, as they reacted to a phenylthiocarbamide (PTC) impregnated paper strip placed on their tongues. We measured their weight, height, waist and hip circumferences, total body fat and lean body mass. Mean and standard deviation is shown to express quantitative variables, Kruskal-Wallis test and Dunn's multiple comparison test was used, with 95% confidence intervals.

PTC tasters comprised 27% of the study group, with non-tasters making up 18%. When analyzed by sex, 32% of women were PTC tasters vs 18% of men. Notably, for men, PTC tasters exhibited higher mean values across several body composition measures than non-tasters, including a BMI of 28kg/m² vs 24kg/m², a waist circumference of 94cm vs 79cm, a waist-to-height ratio of 0.54 vs 0.49, and a body fat percentage of 28% vs 15%. In contrast, women showed no significant differences in these measures based on their bitterness perception.

The distribution of perception groups and preponderance of female PTC tasters corresponds to previously reported data. Taster men had a body composition distant from healthy parameters and above the non-tasters values, yet not significant differences were found for female participants.