Ability to 'smell' with mouth diminishes with age
Another study provides proof that the ability to “smell” with one's mouth diminishes for many as they age. The results have implications for senior living community dining amenities for residents.
Tyler Flaherty, a master's degree student, and Juyun Lim, Ph.D., an associate professor of food and technology at Oregon State University, recently studied how people experience odors via their mouths, and whether age or gender has an influence on it. This so-called retronasal smell comes into play when molecules are released during the chewing of food and then drift through the mouth to the back of the nose, where the odor is detected.
Their results were published in the journal Chemosensory Perception.
Participants in the study — 102 nonsmoking, healthy people aged 18 to 72 years — rated how intensely they picked up on two tastes (sweet and salty) and four odors (strawberry, vanilla, chicken and soy sauce). They also were exposed to these smells in combinations meant to complement one another, such as sweet and vanilla, or salty and chicken.
Age diminished study participants' power to smell more than it did their ability to taste. Many of the older adults found it difficult to pick out specific odors. They fared better, however, when individual smells where presented to them in combination with other tastes — for instance strawberry with sugar. No real differences existed in how participants in the various age groups rated individual tastes, but younger ones were slightly better at detecting vanilla and soy sauce odors.
“Generally, large individual differences in odor responsiveness become even greater when aging is considered as a factor,” Flaherty said.
The findings are in line with previous research findings that people's ability to smell declines as they age, they authors said. Prolonged use of medication, physical and mental changes associated with older age, and the use of dentures may be factors, they said.