Dr Chong Yaw Khian, a senior consultant at Tan Tock Seng Hospital’s Sleep Disorder Clinic, tells Joyce Lim how people can get the ZZZs they need
The Straits Times (17 December 2018) - According to various sleep surveys, Singaporeans are among the world’s most sleep-deprived people.
In an online poll conducted in June and July this year across 12 countries, Singapore took the second spot after Britain. And in a 2014 survey of 43 cities, the Republic came in third after Tokyo and Seoul.
What is keeping Singaporeans awake at night?
Why Sleep Eludes You
There are many causes of sleep deprivation. Most are linked to the Singapore culture of working long hours, according to Dr Chong Yaw Khian, senior consultant at the Sleep Disorder Clinic in Tan Tock Seng Hospital.
The stresses of daily life, such as deadlines and examinations, may affect your ability to sleep well or perhaps it could be because you prefer to trade sleep for more work or play.
“In our increasingly connected world, there are always some activities happening round the clock. Coupled with the constant lure of the Internet, it should come as no surprise that a typical working adult or teenager will not clock the obligatory seven hours of sleep,” says Dr Chong.
The situation tends to be aggravated towards the end of the year when late-night festive activities can mean less sleep. Lifestyle-related behaviour is the major cause of insufficient sleep among the majority of Singaporeans.
Sleep deprivation can also be due to underlying medical conditions, the most common of which are chronic insomnia and obstructive sleep apnea.
Obstructive sleep apnea is a respiratory problem that interrupts sleep. For those who suspect they may have a condition that is causing them poor sleep, Dr Chong recommends consulting a sleep specialist.
How Much Sleep Do You Really Need?
The amount of sleep you need depends on various factors, the most important being your age. Other factors are:
Pregnancy: Changes in the body during early pregnancy can increase the need for sleep.
Ageing: Older adults need about the same amount of sleep as younger adults. However, as you get older, your sleeping patterns might change.
Older adults tend to sleep more lightly and for shorter time spans than younger adults. If you are sleep deprived, the amount of sleep you need increases.
Sleep quality: If your sleep is frequently interrupted, you are not getting quality sleep. Underlying medical conditions can affect the quality of sleep. For example, a patient with obstructive sleep apnea may not be able to get good quality sleep regardless of the number of hours.
What Sleep Deprivation Does to You
Some people claim to feel rested with just a few hours of sleep a night, but are unaware that their performance is likely to be affected, cautions Dr Chong.
If you are getting by on just six hours of sleep instead of the recommended seven or eight hours, in time you will feel that you have adapted to fewer hours of sleep.
But the results of people who do not sleep enough in mental alertness and performance tests “continue to go downhill”, says Dr Chong.
"So there’s a point where we lose touch with how impaired we are.” Chronic sleep deprivation significantly affects your health, work performance, safety and general sense of well-being.
Sleepiness Can Lead to Accidents
Sleepiness can slow reaction time as much as drunk driving. Sleep loss and poor-quality sleep can lead to road accidents and injuries on the job.
In one study, workers who complained about excessive daytime sleepiness had significantly more work accidents, particularly repeated work accidents.
Sleepiness makes you lose focus and impairs your performance Lack of sleep impairs attention, alertness, concentration, reasoning and problem-solving ability.
During the night, various sleep cycles play a role in consolidating memory as well as transferring short-term memory (from the hippocampus) to the long-term memory (in the neocortex of the brain).
If you do not get enough sleep, you will not be able to remember what you have learnt and experienced during the day.
Sleepiness can lead to clinical depression Insomnia and depression feed off each other. Sleep loss often aggravates the symptoms of depression, which, in turn, makes it more difficult to fall asleep.
A study shows that chronic insomnia, the most common sleep disorder among seniors, is strongly linked to depression.
Lack of sleep ages your skin Most people have experienced sallow skin and puffy eyes after a few nights of missed sleep.
When you do not have enough sleep, your body releases more of the stress hormone cortisol, which breaks down the collagen in your skin and leads to wrinkles and sagging.
Sleep loss also causes the body to under-produce human growth hormone (HGH), which is essential for the body to repair and renew itself.
Poor Sleep Can Lead to Weight Gain
Consistent research has shown that the lack of sleep is related to an increase in hunger and appetite, and possibly leads to obesity. Recent research has focused on the link between sleep and the hormones that regulate appetite.
Ghrelin stimulates hunger and leptin signals satiety to the brain and suppresses appetite. Insufficient sleep is associated with elevations in ghrelin and decreases in leptin.
Not only does lack of sleep appear to stimulate appetite, but it also makes you yearn for high-fat, high carbohydrate foods.
Sleep deprivation can lead to serious health problems Sleep disorders and chronic sleep loss can put you at risk for heart disease, hypertension, stroke and diabetes.
According to some estimates, 90 per cent of people with insomnia – a sleep disorder characterised by trouble falling and staying asleep – have another health condition.
Lack of Sleep May Increase Risk of Death
A study showed that subjects who had cut their sleep from seven to five hours or less a night nearly doubled their risk of death from all causes. In particular, lack of sleep doubled the risk of death from cardiovascular disease.
Lack of Sleep Can Impair Sex Drive
Sleep specialists say that sleep-deprived men and women report lower libidos and less interest in sex. Depleted energy, sleepiness and increased tension may be largely to blame.
For men with sleep apnea, there may be another factor in the sexual slump. A study published in the Journal of Clinical Endocrinology & Metabolism in 2002 suggests that many men with sleep apnea also have low testosterone levels.
Nearly half of those who suffered from severe sleep apnea secreted abnormally low levels of testosterone during the night.