Insomnia sufferers should rest easy as the largest ever study into the lack of sleep found it does not cause an early death.
A review of more than 36million people revealed there is no evidence struggling to nod off or waking in the night affects mortality.
But a critic argues that while the majority may be able to cope with a few sleepless nights, for some the health consequences can be devastating.
The largest ever study into lack of sleep found insomnia does not cause an early death (stock)
In the first review of its kind, researchers from Flinders University, Adelaide, analysed 17 studies investigating a possible link between insomnia and mortality.
The studies were carried out all over the world for an average of 11 years. Most were made up of patients who self-reported insomnia, while some were officially diagnosed.
Insomnia was defined as either being frequent – struggling to nod off on three or more nights a week – or ongoing – sleeplessness lasting more than a month.
Results suggest that while insomnia may lead to everything from depression and anxiety to diabetes and dementia, it does not actually affect a person’s lifespan.
The study was published in the journal Sleep Medicine Reviews.
The researchers, led by Dr Nicole Lovato, believe this should reassure those who toss and turn at night that they are not more likely to pass away prematurely.
But, they stress, only 17 studies were analysed, which all had a relatively short follow-up time. Longer trials are therefore required to confirm the findings.
They also note cognitive behavioural therapy, which aims to help insomniacs develop coping skills, correct attitudes about sleep and modify poor habits, remains the gold standard of treatment.
But Dr Russell Foster, head of the Sleep and Circadian Neuroscience Institute at the University of Oxford, argues insomnia can be serious for some.
He told The Times: ‘We recently did a study on teenage sleep. If you just took the average, you would think, “What is all the fuss about?”.
‘However, if you look at the spread of the data you can see 30 per cent are showing really poor sleep.’
For these select few, insomnia may be extremely serious, he added.
Insomnia is the most common sleep disorder, affecting between 10 and 30 per cent of people.
It is generally defined as difficulty nodding off, staying asleep or feeling exhausted during the day.
Previous studies have suggested a lack of sleep increases a person’s heart rate and the time between beats, which was thought to lead to an early death.
However, the current study’s authors argue evidence supporting this is limited, with many studies being small and not adjusting for factors such as smoking or obesity.
This comes after scientists discovered a ‘sleep switch’ that may be essential to a decent night’s shut eye last month.
A cluster of cells in the region of the brain responsible for sleep become activated as mice are nodding off, according to a study by the Beth Israel Deaconess Medical Center.