Study links lack of sleep and weight gain in adults with cardiometabolic risk

Behind the research are scientists from Columbia University (United States), who point out that the findings suggest that strategies to promote adequate sleep duration should be incorporated into weight control and cardiometabolic disease prevention programs.

To reach these conclusions, which are published in the journal Annals of Internal Medicine, The researchers combined data from two randomized trials that included 95 adults aged 20 years or older with cardiometabolic risk factors who routinely slept at least seven hours a night.

They completed two sleep conditions: six weeks with their usual sleep and six weeks with a reduction of approximately 1.5 hours per night – the volunteers were instructed to delay their usual bedtime by 90 minutes – reports the American College of Physicians (publisher of the aforementioned magazine).

Throughout each phase, sleep and activity levels were measured with a wrist monitor, along with changes in body weight, waist circumference, body composition, and fasting levels of several hormones known to increase or suppress appetite.

The findings indicate that those who reduced their sleep by approximately 1.5 hours per night for six weeks gained weight and became more sedentary. (Inactivity time increased an average of 17 minutes per day overall and almost 30 minutes per day for men and postmenopausal women.)

This is significant, since more sedentary people have a higher risk of suffering from chronic diseases, the authors recall.

Additionally, in a study conducted with a subgroup of the same participants, the team reported that women at higher cardiometabolic risk who reduced their sleep had greater insulin resistance, a risk factor for type 2 diabetes.

The effects were more pronounced in those who had already gone through menopause, reports a statement from Columbia University.

The team also found that both men and women at high cardiac risk showed an influx of inflammatory cells into the heart after mild sleep restriction.

“Although more research is needed to better understand how sleep restriction leads to weight gain, all of our findings suggest that lack of sleep increases the risk of obesity-related conditions, such as type 2 diabetes and heart disease,” concludes Marie-Pierre St-Onge, director of the study.

In his opinion, focusing solely on eating a healthier diet and engaging in more physical activity to counteract weight gain is “a simplistic view” and can be difficult to maintain.

Among the limitations of the study, the sample size and that the population analyzed already had a high cardiometabolic risk.