A consistent bedtime doesn’t just lead to more productive mornings — it may lead to weight loss among women and contribute to a heart-healthy lifestyle, a small study shows.

Women who went to bed at the same time every day lost about one pound of body fat over six weeks compared to women whose bedtimes varied, even though both groups got the same seven to nine hours of sleep each night.

“This improvement in body composition occurred without any recommendations for weight loss or tips to change their diet, eating or exercise — all they did was sleep on a more consistent schedule,” lead study author Marie-Pierre St-Onge said in a news release. St-Onge is an associate professor of nutritional medicine and director of the Sleep Center of Excellence at Columbia University Irving Medical Center in New York City.

“The key message is that people should try to go to bed at consistent times every night and wake up at the same time every morning.”

The preliminary research, presented at the American Heart Association’s Epidemiology and Prevention/Lifestyle and Cardiometabolic Health Scientific Sessions, studied 37 women ages 22 to 46 whose body weight was either normal or overweight.