Professor Michael WL Chee, Duke-NUS Graduate Medical School and PI of the Cognitive Neuroscience Lab
Many of us aspire to live life to the fullest but realizing this goal requires thoughtful planning. Staying in good health to enjoy the fruits of our labor does not occur by chance. Balance is important when making lifestyle choices to increase the likelihood that we stay healthy. For example, while eating is essential for sustenance, over-eating results in obesity. Similarly, the many benefits of physical exercise can be eroded by overtraining and not giving our body time to recover. This programme from AIA gives you an opportunity to balance your health portfolio in a frequently neglected area- Sleep.
Modern lifestyles increasingly steal time from sleep. Unceasing targeted marketing has us constantly yearning to ‘get more out of life’ and causes us to feel bad if we don’t. But make no mistake about it, sacrificing sleep comes at personal as well as community costs. It has been estimated that developed economies suffer a loss of 2-3% of their annual GDP as a result of insufficient sleep. In the short term, sleep loss decreases cognitive performance, makes us moody and is associated with feelings of tiredness. Longer term, we put ourselves at risk of diabetes, heart attacks, stroke, early cognitive decline, dementia, some types of cancer, mental illness, accidents and lowered productivity. When parents fail to adopt good sleep habits, it is likely that their children will follow suit. When this is repeated across families, whole communities are put at risk.
Research conducted by my group and others has shown that on average, East Asians wearing sleep trackers sleep between 25-65 minutes less than their counterparts in Australia and New Zealand, across life. The differences are most prominent when comparing older adolescents and young adults, likely reflecting the influence of lifestyle differences across countries, particularly in the young. Why is this important?
Could young Asians have adapted to short sleep? In a series of quasi-laboratory studies my group found that even highly motivated adolescents show cumulative decline in sustained attention if they have only 6.5 hours of sleep at night for 5 nights in a row. 6.5 hours of nocturnal sleep is below what is recommended (that being 8-10 hours, with 7 hours being possibly adequate). We chose 6.5 hours because that is the duration Singaporean adolescents report sleeping on weekdays. In addition, memory and mood were also impaired. It thus appears that even high performing adolescents need their sleep and that if they don’t, dozing in class will likely take place.
Skeptics will point out that in terms of life expectancy, East Asians aren’t faring badly. However, this could well be that the long-term effects have not had time to fully manifest. One is reminded of the myopia epidemic in East Asia. From the 1970’s to the 1990’s the prevalence of myopia in young persons increased from 25% to over 80%. This is important because the earlier a person starts developing myopia, the more severe it becomes later in life. Interestingly, older persons from the same ethnic group were less likely to have myopia. Also, Asians living in Australia were less prone to the condition. Both these observations suggested that an environmental factor was at play. The heavy study culture was initially fingered but current thinking is more nuanced, and points to reduced exposure to natural light in students living in Asia as the culprit. Several scientific trials showing the benefit of increasing daily light exposure and physical activity through outdoor play, support this idea, but it’s taken over two decades and the damaged eyesight of multitudes to come to this point. Can we afford for history to repeat itself with regard to sleep, health and wellbeing when arguably the stakes are higher and we should know better?
It is undeniable that the prevalence of obesity and diabetes has increased dramatically in East Asia. While dietary changes and reduced physical activity play a part, the contribution of poor sleep has been insufficiently acknowledged. Experimental evidence from tightly controlled laboratory studies on sleep deprivation reveal a number of physiological changes that could, in the long run, increase the risk of diabetes. Epidemiological evidence shows a clear association between short sleep and increased risk of diabetes. Yet, an April Fool’s joke was made about a programme to incentivize sleep in computer science students who pride themselves as ‘modern day warriors’ in staying up all night to code. It may be cool to ignore sleep but is it advantageous to do so as many wish to believe?
Clearly not, and happily, the tide is turning. Professional athletes are recognizing the importance of sleep as a contributor to peak performance and speaking out. Burnout has been recognized by the WHO as a medical condition. Sleep is entering the conversation in homes and corporate wellness programmes. And insurance companies are recognizing that improving sleep is a strategy to embrace.
What can we do to improve our sleep? Among the many tips that are circulated in wellness magazines and blogs, only some are supported by scientific evidence. Over a series of articles, I will expand on tips you can trust, but here, I’ll start with the ones that are going to have the largest effect on your life.
Tip #1: Sleep earlier. Persons in East Asia sleep less on weekday nights compared to Westerners primarily because they go to bed late. Students report homework as a significant issue but privately, a number of students say it’s also about what they do in between homework that delays bedtime. Research has shown that academically stronger students sleep earlier and get more sleep. Perhaps they implicitly know about the competitive advantage good sleep gives. Working adults often have greater discretion over their time-use but too few persons exercise their choice, resulting in filling up the night with activities that push back bedtime.
Tip #2: Manage your internet interaction time. Explosive growth in mobile phone adoption has been accompanied by the enslavement of multitudes who feel compelled to constantly stay in touch with one another. Among the ~90% of adolescents and young adults in Asian cities who own a smartphone, ‘communications’ through social media is the most common use. Perhaps unsurprisingly, older persons in our region who have not grown up with instant messaging tend to have less sleep deficit, but even they seem to be affected by the community habit of sleeping late. Without doubt, the internet is an important source of information and opens convenient channels for commerce. However, it remains that major internet-related companies are extremely skillful at manipulating behavior and drawing customers’ time and attention to their digital wares. Supporting the notion that giving in to digital temptations, especially in the evening erodes sleep, a recent study conducted in Germany found that the availability of broadband internet services was associated with 25 minutes less nocturnal sleep than in regions where there was no access.
Tip #3: Have a wind down routine before you go to bed. Falling asleep and staying asleep is accompanied by reduced responsiveness to the external environment. To facilitate this deliberate, often arousing or stressful mental activity should be curtailed. Examples of such sleep inhibitors include worrying about a family member, thinking of how to compose an email or pondering a challenging issue. An overactive mental state works against falling asleep. When we are still young and sleep signals are strong, such mental activities may not yet be a problem. However, many conscientious persons start encountering difficulty initiating sleep from middle adulthood onwards if they do not make a deliberate effort to disengage themselves from their worldly concerns before bedtime. What serves to relax varies from person to person. Some prefer listening to music, others find reading a book or even taking a stroll prior to bedtime relaxing. Some persons take only a few minutes to shut down, others longer. They key point is to ringfence pre-sleep down time and to stick to that resolution.
Tip #4: Strive to focus on the task at hand. High intensity physical training, that previous generations of athletes called ‘interval training’ has found a strong resurgence with young people because if one can tolerate it, it can produce impressive results in less time. If we took this same approach to work or study, we will likely get what we need done and have more time to enjoy some leisure and sleep better. Conversely, persons who do not get enough good quality sleep feel fatigued, sleepy, or both, reducing their willingness to put in the concentrated effort that elevates productivity. Allied with this, sleepy, tired persons are likely to procrastinate, to defer important tasks till they feel better. This could in turn result in staying up later and if the cycle is not broken, not only will productivity be reduced, a person’s expectation of what they are capable of could diminish.
Tip #5 which lies at the top of the list is simply: value your sleep and listen to your body. If you are health conscious, you’d object if someone smoked a cigarette next to you; so why is it many of us don’t reign in the habit of staying up late to respond to social media posts? Or tell your overseas colleague that they need to think about your wellbeing and productivity when a conference call is scheduled past midnight?
If you frequently feel sleepy the next day, fall asleep when left in a quiet room; if you sleep more than two hours more during days when you don’t have to wake up early in the morning, your body is telling you that it is not getting enough sleep. Over the longer term, that’s going to have negative consequences no matter what your friends or colleagues tell you. As habits are difficult to change, it is important to ingrain a positive attitude to sleep when one is young. When one is older it may be difficult or impossible to get the sleep that one craves.
As sleep gains traction as a status symbol, there will be an emergence of ‘sleep hacks’ and ‘super tips’ that basically tell of shortcuts and ways one can benefit sleep without making significant lifestyle changes. Such advice can be likened to liposuction and facial uplifts – may look good from the outside but don’t actually change the underlying fundamentals. As prudent investors, you need to be wiser.
Investing in good sleep is a wise move. Something to sleep on tonight.