Federal Grant Award Summary

The National Institute on Deafness and Other Communication Disorders (NIDCD) awarded a $603,750 Project Grant to the University of California, Davis for the period April 1, 2026 through March 31, 2029 under the Research Related to Deafness and Communication Disorders program (CFDA 93.173). This research initiative investigates the mechanisms by which non-sugar sweeteners reduce bitter taste perception, addressing a critical public health issue where bitter-tasting medications, bioactive compounds in nutritious foods, and psychoactive substances in beverages lead to poor medication compliance, avoidance of healthy foods, and excessive sugar consumption. The project delivers two primary research products: (1) human sensory panel studies using the established split-tongue paradigm with 60 healthy adult participants to determine both peripheral and central mechanisms of bitter suppression by seven common sweeteners paired with two distinct bitter compounds, and (2) cellular receptor-based assays testing these sweeteners against eight human bitter taste receptors activated by the bitter compounds.

The research aims to fill a significant gap in understanding dual-mechanism bitter suppression—which may provide additive effects through both central cognitive suppression in the brain and peripheral suppression on the tongue—and to identify which sweeteners most effectively suppress bitterness. The findings will enable more informed prediction of which non-sugar sweeteners are most potent for reducing bitter taste and improve formulation strategies for medications and health-promoting beverages, ultimately supporting better patient compliance and dietary adherence.