Want to stay slim? Getting eight hours of shut-eye daily may be one of the simplest ways, a new
study has claimed.

A team of international researchers has found that people who sleep for less than six hours a night - or more than nine - put on more weight than those who sleep for seven or eight hours daily, 'The Daily Telegraph' reported today.

The reason that the amount of sleep a person gets can govern his or her weight is because sleep affects hormones levels, especially those involved in appetite and feeling full after a meal, the study has suggested.

According to lead researcher Jean-Philippe Chaput of Laval University in Quebec, ''Our study provides evidence that both short and long sleeping times predict an increased risk of future body weight and fat gain in adults.

''Furthermore, these results emphasize the need to add sleep duration to the list of environmental factors that are prevalent in our society and that contribute to weight gain and obesity.

''Since preventing obesity is important, a pragmatic approach adding sleep hygiene advice to encouragement towards a healthy diet and physical activity may help manage the obesity epidemic.''