Lack of sleep
Lack of sleep increases risk of aggressive breast cancer.

People who do not sleep at least eight hours a day tend to eat too much and thus be more likely to become fat, according to a new study.

Researchers from Mayo Clinic have discovered that people who sleep less eat up to more than 500 additional calories, compared to someone getting enough sleep.

Researchers had conducted a study on 17 individuals aged between 18 and 40, for eight nights. Among the 17 individuals, half of them slept a normal amount, whereas the other half slept only for a few hours. They discovered that the sleep-deprived group had eaten more compared to the other group.

Less sleep was always linked with increased levels of leptin, a hormone that suppresses appetite and decreasing levels of ghrelin, a hormone that is thought to trigger hunger.

Now researchers have discovered that increase in leptin and decrease in gherlin make people eat more.

"Sleep deprivation is a growing problem, with 28 per cent of adults now reporting that they get six or fewer hours of sleep per night," Andrew D Calvin, assistant professor of medicine at the Mayo Clinic told the Times of India.

Max Hirshkowitz, a board member of the National Sleep Foundation and a professor at the Baylor College of Medicine, told the Huffington Post that it was a surprising finding that sleep-deprivation increased leptin. "So they wound up concluding that the ghrelin and leptin changes are not coming from sleep deprivation, but from the fat. The hormones are probably responding to the feeding behaviour," he added.