Sleep loss caused a 23 to 24 percent increase in hunger, translating into an extra 350 to 500 kilocalories a day, "which for a young sedentary adult of normal weight could lead to a major amount of added weight," Spiegel said according to Agency France Presse.
Among the first studies was conducted in 1992 in France, which highlighted the problem in children and teenagers. Spiegel said the increase in obesity in the US in the second half of the 20th century corresponded with a significant decrease in sleep.
There are two hormones produced at night that help regulate appetite. Grehlin makes people hungry, slows metabolism and decreases the body's ability to burn body fat. Leptin, a protein hormone produced by fatty tissue, regulates fat storage.
According to INSERM, sleeping more may be the key in slimming down or losing weight. It also cited that poor eating habits and lack of exercise play a major role in the rise of obesity globally, but lack of sleep as a factor is often under-estimated.
