When Andrew Dillin, a cell biologist at the University of California Berkeley, set out to study the effect of the sense of smell on weight in mice, he assumed that he’d find that mice without a sense of smell would enjoy food less, eat less, and therefore weigh less. Scientists have known that smell shapes the way we tastes things—usually for the better—so without it, mice eating even a scrumptious, high-fat diet would enjoy it less.
He was right—kind of. The results of work he and his team published on July 5 in the journal Cell Metabolism show that adult mice without a sense of smell did weigh about 16% less than those with their sniffers intact. But the reason came out of left field: It was because somehow, without a sense of smell the rodents burned more energy from fat.