The less you sleep, the more likely you are to develop diabetes, obesity and hypertension.
Getting less than six hours of sleep per night poses a health risk.
About 20 percent of the population in the United States and Britain sleeps less than five hours.
Sleeping more than nine hours has also been linked to premature death.
People who get less than six hours sleep per night have an increased risk of dying prematurely, researchers said on Wednesday.
Those who slumbered for less than that amount of time were 12 percent more likely to die early, though researchers also found a link between sleeping more than nine hours and premature death.
"If you sleep little, you can develop diabetes, obesity, hypertension and high cholesterol," Francesco Cappuccio, who led research on the subject at Britain's University of Warwick, told AFP.
The study, conducted with the Federico II University in Naples, Italy, aggregated decade-long studies from around the world involving more than 1.3 million people and found "unequivocal evidence of the direct link" between lack of sleep and premature death.