A new study from the Spanish National Centre for Cardiovascular Research has identified a link between lack of sleep and obesity in teenagers.
Teenagers who sleep less than eight hours a week are more likely to be overweight than those with sufficient sleep, according to research presented at the European Society of Cardiology’s annual congress for 2022. Not only has insufficient sleep been linked to obesity in teenagers, but correlations have also been made between poor sleep and high blood pressure, as well as abnormal blood lipid and glucose levels.
“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,” said study author Jesús Martínez Gómez, a researcher in training at the Cardiovascular Health and Imaging Laboratory, Spanish National Centre for Cardiovascular Research.
How the research was carried out
The study examined the relationship between sleep duration and obesity in teenagers, by analysing data from 1,229 adolescents in Spain. Each participant’s sleep was measured for seven days using a wearable activity tracker, this was repeated three times for each participant at the ages of 12, 14, and 16. Eight hours of sleep was considered the optimal amount by the researchers. Participants were categorised as very short sleepers (less than seven hours), short sleepers seven to eight hours), and optimal (eight hours or more). Participants were made up of an equal number of boys and girls.
The level of obesity in teenagers was determined according to the body mass index of the participant. Researchers also calculated a continuous metabolic syndrome score for each participant ranging from negative (healthier) and positive (unhealthier). These scores were assessed by considering the waist circumference, blood pressure, blood glucose, and lipid levels of each participant.
Only 34% of participants slept at least eight hours at the age of 12, this dropped to 23% at 14 and 19% at 16, with boys typically getting less sleep. It was found that teenagers who got the most sleep also experienced better quality sleep, meaning they woke up less during the night. Obesity was prevalent in 27% of 12-year-old, 24% of 14-year-olds, and 21% of 16-year-olds.
12-year-olds in the very short sleeper category were found to be 21% more likely to be obese than those with optimal sleep, while very short sleepers aged 14 were 71% more likely to be overweight or obese. Participants were deemed as short sleepers 19% and 29% more likely to be overweight or obese compared with optimal sleepers at 12 and 14 years, respectively.
More action needed to tackle obesity in teenagers
“The connections between insufficient sleep and adverse health were independent of energy intake and physical activity levels, indicating that sleep itself is important,” said Gómez
Gómez also suggested more needs to be done by authorities to tackle obesity in teenagers. “Excess weight and metabolic syndrome are ultimately associated with cardiovascular diseases, suggesting that health promotion programmes in schools should teach good sleep habits. Parents can set a good example by having a consistent bedtime and limiting screen time in the evening. Public policies are also needed to tackle this global health problem,” he added.
