Children and teenagers who do not get enough sleep have an increased risk of becoming obese, the results of a new study have found.

UK researchers analysed 42 studies involving over 75,000 children and teenagers up to the age of 18.

The participants were put into one of two groups:
-Short sleepers, who got less than the recommended amount of sleep for their age group
-Regular sleepers, who got enough sleep.

Current US guidelines recommend that infants aged between four and 11 months get between 12 and 15 hours of sleep per night. Toddlers aged one to two years need 11 to 14 hours of nightly sleep, while children aged three to five years need 10 to 13 hours. Children aged six to 13 require between nine and 11 hours per night, while teenagers aged 14 to17 are advised to get eight to 10 hours.

The participants in the study were followed up for an average of three years and changes in body mass index (BMI) were monitored.

The researchers found that at all ages, short sleepers gained more weight overall and were 58% more likely to become overweight or obese.

"The results showed a consistent relationship across all ages indicating that the increased risk is present in both younger and older children. The study also reinforces the concept that sleep deprivation is an important risk factor for obesity, detectable very early on in life," commented one of the study's co-authors, Dr Michelle, Miller of the University of Warwick.

She warned that being overweight can lead to cardiovascular disease and type 2 diabetes.

"The findings of the study indicate that sleep may be an important potentially modifiable risk factor or marker of future obesity," Dr Miller added.

The researchers said that while healthy eating and exercise are important, this study suggests that getting enough sleep is equally important.

Details of these findings are published in the journal, Sleep.