Impact of bitter taste on gastric motility

Background Unexplained nausea and vomiting is often associated with delayed gastric emptying in patients with functional dyspepsia. We hypothesized that the experience of an unpleasant, nauseating taste could lead to a delay in gastric emptying. Methods Sixteen healthy women consumed a bland liquid test meal on three separate study days. On two of the study days subjects sham fed either a bitter tasting, modified Slim-Fast bar or one with a pleasant strawberry flavour. The time for 50% gastric emptying (GE(50)) was non-invasively assessed by electrical impedance tomography and antral motility by electrogastrography (EGG). Results Gastric emptying was significantly delayed by sham feeding the bitter compared with the pleasant bar, GE(50) 24.7 +/- 3.9 versus 17.2 +/- 1.8 min, P < 0.05. EGG power rose significantly during both the pleasant (basal 1.46 +/- 0.07 to 2.33 +/- 0.14 log(10) mu V-2/min, P=0.000) and the bitter sham feed (basal 1.64 +/- 0.09 to 2.35 +/- 0.11 log(10) mu V-2/min, P=0.000). Conclusion An unpleasant bitter taste delays gastric emptying but does not significantly impair antral motility.