Less Sleep Hours In Teenagers Linked To Obesity, Study Finds

According to a recent research, presented at ESC Congress 2025, teenagers who sleep less than eight hours per night are more likely to be overweight or obese than their peers who take a good amount of sleep.

Adolescents who sleep for shorter periods were also highly likely to have a number of other unhealthy characteristics such as too much fat around the belly, high blood pressure, and abnormal blood lipid and sugar levels.

The study was conducted to analyse the link between sleep duration and health status in 1,229 teenagers in the Program for Secondary Schools trial in Spain. The participants had an average age of 12 years with an equal number of boys and girls.

Sleep was tracked for seven days and there was a wearable tracker three times in every participant at the ages of 12, 14, and 16 years.

The American Academy of Sleep Medicine recommends sleeping for nine to twelve hours a night for 6 to 12 year old children and eight to ten hours for 13 to 18 year old teens, for optimum health. To examine the study simply, they considered 8 hours or more as optimal. Participants were grouped into categories of very short sleepers (less than 7 hours), short sleepers (7 to 8 hours), and optimal sleepers (8 hours or more).

Study author Mr. Jesús Martínez Gómez, who is a researcher in training at the Cardiovascular Health and Imaging Laboratory, Spanish National Centre for Cardiovascular Research (CNIC), Madrid, Spain, said, "Our study shows that most teenagers do not get enough sleep and this is connected with excess weight and characteristics that promote weight gain, potentially setting them up for future problems.

" He further added, "We are currently investigating whether poor sleep habits are related to excessive screen time, which could explain why older adolescents get even less sleep than younger ones."

Overweight and obesity were identified as per the body mass index (BMI). The researchers measured a continuous metabolic syndrome rate ranging from negative (healthier) to positive (unhealthier) scores, including waistline, blood pressure, and blood sugar and lipid levels. In 12 years of age, only 34 per cent of participants slept up to 8 hours in a night, and this dipped to 23 per cent and 19 per cent at 14 and 16 years of age, respectively.

The results also showed that boys tended to get less sleep. Teenagers who got optimum sleep also had good sleep quality, showing that they woke up less at night and spent more time in bed sleeping than those with lesser sleep. The linked of obesity was 27 per cent, 24 per cent and 21 per cent at 12, 14 and 16 years of age, respectively.