BOB HIRSHON (host):
A mouth-watering hormone…I’m Bob Hirshon and this is Science Update.
Our ability to smell is heightened when we’re hungry. This makes evolutionary sense, because a good sense of smell helped our ancestors sniff out calories and avoid famine. Now researchers think a hormone called ghrelin, which is already known to increase appetite, makes us use our noses more. University of Cincinatti endocrinologist Jenny Tong and her colleagues gave the hormone to rats, causing them to sniff more frequently than usual. They then gave ghrelin to people and had them smell five different odors.
JENNY TONG (University of Cincinnati):
And when they received ghrelin, they sniffed harder as compared to the time when they received just saline, salt solution.
In the future, she says ghrelin could help older people retain their sense of smell. And blocking the hormone could combat obesity, by making high calorie foods less appealing. I’m Bob Hirshon, for AAAS, the science society.