Fat Perception in Humans (09-0873)

1. Determine the effect of lipolysis inhibition in oral cavity on orosensory detection of fat in humans. Hypothesis: Orally applied Orlistat will increase detection thresholds of TAGs but not FFA in humans. To test this hypothesis we will measure triolein (a TAG) and oleic acid (a FFA) taste detection thresholds with a three-alternative forced-choice (3-AFC) ascending concentration method under two conditions (Orlistat day vs. Control day). To control for olfactory input, subjects will be assessed wearing noseclips. 2. Determine the effect of CD36 variants on fat taste perception in humans. Hypothesis: SNPs that associate with reduced CD36 expression will be associated with higher FFA and TAG detection thresholds To test this hypothesis we will measure triolein and oleic acid taste detection thresholds in subjects who carry of the common CD36 e-SNP rs1761667 (i.e. a SNP that significantly reduces CD36 level and has a minor allele frequency of 38-48%). We expect subjects who are at least heterozygous for the expression reducing allele to have higher triolein and oleic acid taste detection thresholds compared to non-carrier subjects.