A third of primary school children are not going to sleep until around midnight, according to a new study.
New research from bedmaker Silentnight and the University of Leeds found 36% of primary school age children get eight hours or less sleep a night.
And 15% of British youngsters aged 11 or under are heading into school each morning after less than seven hours of shut eye.
Now psychologist Dr Anna Weighall is urging parents to help their children have at least 10 hours of sleep daily, to boost their quality of life and avoid mental health problems.
She said: "Our research, carried out in conjunction with Silentnight, shows a strong relationship between poor sleep and reduced health related quality of life.
"Mental ill health can have a negative impact on sleep," Dr Weighall continued.
"Likewise, poor sleep patterns can make mental health issues worse.
"I certainly think that lack of sleep can make mental health issues worse."
A Harvard University study, from 2009, showed that 90% of children with major depression have some kind of sleep problem.
It claimed over half of insomnia cases related to depression, anxiety or psychological stress. It also linked poor sleep with disorders like ADHD and autism.
Studies also claim those struggling with sleep are more likely to be irritable and lacking in concentration, impacting academic development, causing problems paying attention in class and keeping up with school work.
It can also affect emotional regulation, which can affect peer relationships too.
Psychologists also argue that sleep deprivation decreases the efficiency of something called "top-down inhibition" which enables children to control and regulate their behaviour.
This behaviour has been shown to limit the functioning of the emotional processing at the centre of the brain (the amygdala) which explains the effects of lack of sleep on mood and emotion.
The research from the University of Leeds found among concerns keeping children awake at night were worries about bullying and worries about homework.
An alarming one in six parents who took part in the university’s research said their children’s sleep has been affected by bullying.
The University of Leeds and Silentnight research was conducted with 1,000 UK parents of children aged between 6-11, with an equal gender split.
A previous study from Childwise found one in 10 children is sent to bed armed with an iPhone or iPad, affecting their sleeping patterns.
They claimed so-called ‘iTods’ and their parents now treat "constant access" to tablets and touch screen technology as "extra toppings on an ice cream dessert".
Dr Aric Sigman, a fellow of the Royal Society of Medicine, said: "It is imperative that parents are made aware of young children consuming increasing amounts of recreational screen time in bed.
"More screen devices leads to more screen consumption.
"If parents were to put a refrigerator in their child’s bedroom, that child is likely to eat more.
"And if the fridge contained a choice between broccoli and Ben and Jerry’s ice cream, one can be reasonably confident that the broccoli will never leave that fridge."