Scientists have found a group of molecules in the blood that are associated with sleep quality, paving the way for a simple test to assess whether children are getting enough sleep.
Researchers said their findings could, in future, help devise a blood test that could not only assess whether the children are sleeping well, but also determine whether they are susceptible to other health conditions.
They found that a group of molecules in the blood known as microRNAs (miRNAs) are closely associated with sleep quality.
Fabio Laura, of the Institute of Food Sciences of the National Research Council in Italy, and one of the authors of the study, said: "Our findings show for the first time that the sleep duration reflects the profile of specific circulating microRNAs in school-aged children and adolescents.
"This could allow clinicians to easily determine if children are sleeping enough by using a simple blood test and use this as an indication of other aspects of their health."
Sleep is believed to essential for children's health, and the researchers say lack of shut eye can be associated with negative health outcomes, such as heart disease and diabetes.
Study across eight countries
The team studied 111 healthy children and adolescents from eight European countries - Spain, Italy, Cyprus, Germany, Belgium, Estonia, Hungary and Sweden.
Based on self-reporting, the children were classed as "short sleepers" and "normal sleepers".
Short sleepers included children sleeping less than nine hours per day, while normal sleepers were those catching at least nine hours of sleep at night.
Adolescents getting less than eight hours of sleep a day were classed as short sleepers while those sleeping for at least eight hours or more were seen as normal sleepers.
The researchers found that by analysing the profiles of two circulating miRNAs they could tell which children were poor sleepers.
The team took into account the participants' country of origin, age, sex, pubertal status, average daily screen time and educational level of their parents, saying these factors did not affect miRNA profiles.
Based on their findings, the researchers believe a blood test to assess sleep quality "could provide a more reliable metric" than self-reporting.
Mr Laura told the PA news agency: "Our experimental design was addressed to demonstrate that epigenetic mechanisms are involved in sleep duration and patterns.
"It is conceivable that in a near future a simple screening test will be available."
The research is published in the journal Experimental Physiology.
