Why that second piece of pie doesn’t taste as sweet

Scientists have known for a decade one of the ways our taste buds detect sweetness. But when lab mice who had that sugar receptor knocked out could still taste sugar, Robert Margolskee at the Monell Chemical Senses Center in Philadelphia asked why.

“It got us to thinking, ‘Well, gee, what’s going on?’” Monell said. “Is there another sugar sensor? And could that sweet detection mechanism be the same as what the pancreas uses to measure high blood glucose?”

Sure enough, Monell and his team found the sugar sensor that tells the pancreas to release insulin when blood-sugar levels are high is also present in taste cells on our tongues.

Margolskee hypothesizes these sensors may get signals from the rest of the body that tell them when there is a lot of sugar in the bloodstream. That, in turn, may decrease the activity of sweet receptors–making things taste less sweet.

“And that could decrease the sweet drive from the taste cells to make it less appealing or less of a driving force for ingesting that second or third or fourth piece of pie,” said Margolskee.

Margolskee said understanding more about how taste works is an important step in figuring out how to limit consumption of unhealthy foods.