Fatty foods prompt the body to produce a molecule called NAPE — short for N-Acylphosphatidylethanolamine.
The blood stream then carries the NAPE molecule to the brain — where it tells the brain to shut down the appetite. It's a compound that is made from triglycerides, the kind of fat you find in meat.
"We showed that this doesn't increase with carbohydrate feeding, does not increase with protein feeding, just fat feeding," said Gerald Shulman, who conducted the research with his colleagues at Yale University's School of Medicine.
The Yale team showed that doses of synthetic NAPE given to mice and rats led the animals to avoid eating.
Randy Seeley, the associate director of the Obesity Research Center at the University of Cincinnati College of Medicine, says the discovery could be an important tool in helping people struggling obesity. But it could be years before the benefits of the NAPE molecule are fully verified, he said.
Seely says it's important to keep in mind that for the most part, humans are very good about maintaining the proper weight.
"You consume 900,000 calories in a year," Seeley said. "If you were just going to gain one pound, you'd only have to overeat by 4,000 calories." Over the course of a year, that figure equals about 11 calories a day.