Margaret Thatcher famously worked on four hours of sleep per night, but that could have contributed towards her developing dementia and stroke, according to a New Zealand sleep doctor.
“Sleep has a huge impact on cognitive functions, emotions and the physical body. Chronic poor sleep can result in diabetes, heart attacks, stroke and Alzheimer’s disease,” says Dr Alex Bartle from the Sleep Well Clinic.
Dr Bartle, who specialises in sleep disorders, believes that most people do not allow themselves enough time in bed and less than six hours of sleep is not enough.
Ideally, humans need at least six hours per night but seven or eight is optimal and some people function better with nine.
“Sleep is the third pillar of health alongside diet and exercise, so waking up to a five o’clock alarm to go to the gym could be counterproductive if it cuts into your REM sleep.
“We can survive on less for short time periods, just like new mothers do, but in the long term we don’t function,” the doctor said.
Dr Bartle has had patients who have lost their jobs from poor work performance due to insomnia and sleep apnoea.
“Insomnia leads to a slowdown of thinking, concentration and memory fade. We think we can get away with it if some of our work is routine but if an issue comes out of left field then we are going to be much slower at the response.
“Employees would be making bad decisions after only four or five hours of sleep,” he said.
When the body has not had enough sleep, the brain’s glymphatic system (which clears waste for the central nervous system) hasn’t had time to do its job.
Amyloid beta protein is one of the waste products that builds up in the brain if the glymphatic system has not had time to clear out during sleep.
These amyloid beta proteins are also involved in Alzheimer’s disease, being the main element of amyloid plaques found in the brains of Alzheimer’s patients.
There is a difference between amount of sleep and quality of sleep and both are important for productivity and brain function.
“Patients who suffer from insomnia might not be getting enough sleep, whereas those with sleep apnoea will not be experiencing quality sleep,” he said.
Dr Bartle doesn’t prescribe pharmaceuticals for better sleep and instead recommends people with sleep disorders to spend more time outside, do more exercise and cut down their usage of TV, computers and mobile screens.
He recommends not looking at any electronic screen for at least 30 minutes to an hour before bed.
“If you have trouble sleeping early, go to bed later, not earlier. If you still can’t sleep, get up for 15 minutes and then try again. Avoid clock watching and don’t panic if you wake up during the night because it’s normal, most people wake during the night and then go back to sleep, even babies do this,” he said.
“Naps can make up for sleep loss, but only temporarily, so don’t nap for longer than 20 minutes or it might impact your sleep that night,” he said.
Westpac NZ chief executive David McLean says he definitely needs eight hours.
“I would get eight hours a night on average and will often have an afternoon nap in the weekend or on holidays, particularly if I have been travelling or stressed.
“I make sure I don’t have a TV in the bedroom, I turn my phone off and try to read a book before sleep, rather than check emails or social media.
“When I’m trying to get to sleep it’s also helpful to have a ‘happy place’ to think about when my mind starts thinking and fretting about stressful things, like work.”
Dr Bartle also recommends visualisation, meditation and yoga breathing to patients suffering from insomnia, which is usually related to stress but can become a behavioural habit.
“Magnesium supplements can help elderly patients sleep better but they don’t usually do much for people under 55 years old, even though around 50% of people experience a placebo effect,” he said.
Melatonin is another supplement that the doctor is sceptical about for better sleep, however he said it can help those experiencing jet lag.
“If you’re traveling for a two day conference, you can try melatonin, which is 2mg of Circadin but also get some time outside and stay on New Zealand time.
“If you’re away for five nights or more try to adapt to the new time zone,” he said.
Westpac NZ GM of Operations, Leanne Lazarus, says she has a minimum of six hours per night but aims for seven.
“I try to keep to a sleep schedule and track my sleep patterns via my FITBIT. This gives me an insight into my sleep quality and sleep stages,” she said.
Dr Bartle warns that FITBITs can be notoriously inaccurate at measuring sleep stages and quality of sleep.