We all know the foggy feeling after a night of tossing and turning, with scientists now confirming just one bout of insomnia can "significantly impair" our "daily functioning".
Insomnia is thought to affect up to a third of British adults to some extent. The odd night of missed sleep does not have any lasting health consequences. Chronic sleep issues, however, have been linked to heart disease, cancer and even an early death.
To better understand how insomnia affects our emotional wellbeing, scientists from the University of South Florida analysed nearly 2,000 healthy middle-aged adults, who kept sleep diaries for eight consecutive days.
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Getting fewer than six hours of sleep – the lower end of official recommendations – on just one night left the participants feeling angry, nervous, lonely, irritable and frustrated the next day.
They also endured physical symptoms, like aches, gut problems and "upper respiratory issues".
"Many of us think we can pay our sleep debt on weekends and be more productive on weekdays, however, results show having just one night of sleep loss can significantly impair your daily functioning", said lead author Dr Soomi Lee.
The Florida scientists analysed participants of the Midlife in the United States study, of whom just over two in five (42%) had at least one night of poor sleep across the eight days.
Every additional night of poor sleep led to an increase in "daily negative affects", alongside a reduction in "positive affects", the results – published in the Annals of Behavioural Medicine journal – show.
The rate of these effects slowed, however, as the consecutive bouts of insomnia accumulated.
The mental and physical symptoms did not disappear until the participants slept for more than six hours.
Dr Lee has warned that once our body adjusts to getting by on little sleep, it becomes increasingly difficult for us to recover from insomnia, worsening the cycle.
The research comes after the same scientists found losing just 16 minutes of sleep may affect our performance at work.
Mild insomnia has also been linked to a reduced ability to practice mindfulness, which many use to manage stress and maintain a healthy routine.
To ensure good "daily functioning", Dr Lee recommends people set aside at least six hours a night to sleep.
"Making efforts to break the vicious cycle of sleep loss may protect daily wellbeing in adults whose sleep time is often compromised," wrote the scientists.
Tips for a good night's sleep
People who struggle to sleep are advised to go to bed and wake up at the same time every day, even on weekends.
Winding down with gentle yoga, a warm bath, soothing music or a relaxing book can also help. Writing a to-do list for the next day may also calm a frazzled mind.
Experts also recommend people avoid screens, like their phone, for around an hour before bed.
Bedrooms should also be "sleep friendly", with a comfortable mattress, pleasant temperature and black-out curtains, if necessary.
Keeping a sleep diary can help people link a poor night's shut eye to lifestyle habits, like drinking too much coffee or alcohol.
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