A new study found that children who sleep less tend to eat more.

The research team found children who were 16-months-old and got less than 10 hours of sleep per night consumed about 150kcal more per day than those who slept for more than 13 hours, a University College London (UCL) news release reported.

The researchers looked at1,303 U.K. families  who participated in the Gemini birth cohort study, which monitored the sleeping patterns when the children were 16 months old and their diet when they were 21 months old.

The numbers jumped from 982kcal to 1087kcal between the two groups. The study is the first to link sleep to energy intake directly in children under the age of three.

The changes were observed before any weight gain would be prevalent, which suggests that "energy intake is a key pathway through which sleep contributes to weight gain in early childhood," the news release reported.

Researchers are not sure of the exact cause of this increased appetite; they suggest shorter sleep times could somehow affect hormones that work to regulate appetite.

"We know that shorter sleep in early life increases the risk of obesity, so we wanted to understand whether shorter sleeping children consume more calories" Doctor Abi Fisher of the Health Behaviour Research Centre at UCL, said in the news release. "Previous studies in adults and older children have shown that sleep loss causes people to eat more, but in early life parents make most of the decisions about when and how much their children eat, so young children cannot be assumed to show the same patterns.

"The key message here is that shorter sleeping children may prone to consume too many calories," Doctor Fisher said. "Although more research is needed to understand why this might be, it is something parents should be made aware of."