Grant: Discovery Grants Program - Individual

Food & beverage flavor & liking strongly influences what we eat & drink & consequently a range of nutritional & health outcomes. Therefore, individual differences in how we perceive taste & smell ('chemosensory' perception) influence habitual dietary intake & risk of chronic diet-related disease. For example, individuals who sense dietary sugar & fat less intensely may require them in higher concentrations to reach optimal liking & thus habitually consume greater amounts, increasing their risk of energy over-consumption, obesity & related disease states. Genetic variation is a very important source of differences between people in perception of chemosensory stimuli. Two important measures of this are 6-n-propylthiouracil taster status (PTS) & thermal taste status (TTS). The latter is a recently described phenomenon where 20-50% of people experience a phantom taste when small areas of their tongue are rapidly cooled or heated. Interestingly, these individuals (thermal tasters - TT) experience a range of tastes much more intensely than thermal non-tasters, in part because they may possess different variants of TRPM5, a cation channel important in thermal taste & transduction of sweetness, bitterness & umami. Very little is known about the TT phenotype & its underlying genetic basis, thus our main objectives are to (i) fully describe the association between TTS & perception of oral stimuli & odors, including foods/beverages, (ii) determine how TTS associates with liking (a proxy for consumption) of foods/beverages, (iii) determine the relative importance of TTS & PTS in chemosensory perception & food/beverage behavior & (iv) initiate investigation of the genetic variations associated with TT through application of modern genotyping techniques. Through greater understanding of differences in chemosensation, we will gain fuller knowledge of food-related disease aetiology, with application to designing appropriate health care interventions/services. Canadian food/beverage producers will also benefit with respect to optimizing the flavor of their products & subsequent gain in market share & exploitation of market segmentation based on genetic differences in consumer chemosensation.