New studies are shedding light on why people eat unhealthier food and more of it when they don’t get enough sleep, reports The Wall Street Journal.

A small study published in the journal Sleep earlier this month found a new mechanism that helps explain why people who are sleep-deprived are at greater risk of gaining weight. University of Chicago researchers found that 14 individuals who were sleep-deprived consumed nearly 1,000 calories in snacks in the early evening compared with 600 calories when they had a full night’s sleep, and when they were sleep-deprived they ate twice as much fat. Calories consumed at a lunch time buffet remained the same.