Poor Taste Perception May be to Blame for Bad Eating Habits

Age and gender also had a major influence on taste perception. In the study, girls could identify taste qualities significantly better than boys, and advancing age was shown to affect taste sensitivity, with older children scoring higher than younger participants. There were no major differences in total score by ethnicity.

The researchers speculated that differences in taste sensitivity are multifactorial, and that genetic, hormonal and learning effects have an impact. Further, they say, polymorphisms of the genes coding for taste are believed to cause inter-individual differences in taste sensitivity.

There are ways clinicians can assess levels of taste sensitivity. “For example, some researchers would use liquids that are pipetted onto the tongue in various concentrations,” said Thomas Hummel, MD, a professor in the Smell and Taste Clinic at the University of Dresden Medical School in Dresden, Germany and one of the study co-authors. “We used filter paper strips that had been impregnated with the various tastants in four different concentrations each,” said Dr. Hummel. “Following placement on the tongue, participants indicated what taste quality they perceived. These answers produced a score that reflected taste sensitivity.”

The German researchers also established pediatric norms for umami—the fifth human taste, which is best represented by monosodium glutamate. “Those norms have not been previously available,” said Donald Leopold, MD, a professor of otolaryngology at the University of Vermont College of Medicine in Burlington. “They figured out a way. It’s a difficult stimulus to create.” Using the taste strips, the researchers found that obese children were less able than their non-obese counterparts to identify salt, umami and bitter tastes.

Other Factors

Whereas previous studies had evaluated participants’ reactions only to bitter taste, this research assessed all five taste modalities, said Jayant Pinto, MD, an associate professor of otolaryngology at the University of Chicago Pritzker School of Medicine. In addition, it is valuable that the researchers measured not only sensitivity, but also intensity, of response. “This does contribute to the field by sort of suggesting—not only for bitter tastes, but also for other tastes—that lower sensitivity to these tastes may be associated with obesity,” Dr. Pinto said.

What most people perceive as a problem with their taste buds often stems from a problem with their sense of smell, said Allen Seiden, MD, a professor of otolaryngology at University of Cincinnati and a rhinologist with a special interest in taste and smell disorders. “When people lose their smell, they notice that food doesn’t taste right. What they mean is, they’re not getting any flavor, but they interpret that as taste.”