Poor sleep could cause illnesses including psychiatric conditions, attention deficit disorder, post traumatic stress and depression, according to a new study.
Sleep problems have long been associated with mental health conditions, but it was believed that they were a side effect of the disease.
Now, however, American scientists reckon that sleeping difficulties could be the causes of some mental health problems.
"It was just so easy to say about a patient, well, he's depressed or schizophrenic, of course he's not sleeping well - and never to ask whether there could be a causal relationship the other way," the Telegraph quoted Robert Stickgold, a sleep researcher at Harvard University, who believes that sleep problems do cause mental illness, as saying.
However, studies on patients with a condition in which their airway closes over during the night, causing them to stir and lose sleep, suggest the link is causal.
Suffering from the illness, called sleep apnea, significantly raises the chance of suffering from depression, studies have found.
According to researchers, the root cause of sleep apnea is biological not psychiatric, the results prove that it can affect mental health problems.
But scientists do not know how many people could have mental health problems caused by trouble sleeping.
Matt Walker from the University of California, Berkeley, said: "That is very frightening.
"Wouldn't you think that it would be important for us as a society to understand whether 3 per cent, 5 per cent or 50 per cent of people diagnosed with psychiatric problems are simply suffering from sleep abnormalities?"
It is believed that between a quarter and half of children suffering from attention deficit disorder have trouble sleeping, compared to an average of just seven per cent of children overall.
According to the article in New Scientist magazine, studies have shown that treating patients with sleeping pills can alleviate their depression.
Some scientists suggest that a lack of sleep can cause fluctuations in hormones in the body, including those which relate to how we deal with stress.