However, this information is not properly transmitted to the brain, which causes us to look for unwanted food to feel good.
In the study, experts forced 30 people to sleep only for four hours. The next morning, participants were served breakfast, lunch and dinner, as well as a buffet with unlimited snacks such as potato chips and cakes.
The researchers measured how much they ate to see how their choices differed depending on how tired they were. Sleep deprived volunteers chose high-calorie dishes, on average 6%.
However, they generally did not eat more calories. The effects were long-lasting because participants continued to eat high-calorie meals the next day, despite compensating for sleep hours.
During the study, scientists monitored pear bark, the first area of the brain that receives information from the nose. The information is sent to the isolated bark, which lies deep in the brain, where it receives signals about the smell and taste, and the amount of food in the stomach.
Scientists write that these factors influence how much food we will eventually eat. "When you're sleep deprived, these areas of the brain may not get enough information and compensate for this by choosing high-calorie foods," they said.
The study is the last of many to study the basic mechanisms of bad sleep and its relationship to unhealthy food choices.
Previous studies have revealed a number of changes in the body that make people sleep deprived to eat foods high in fat, salt and sugar.