In today’s competition-filled modern society, people often feel the need to rush through things and get more work done, meet tighter deadlines and make more money even if that means they need to work until late at night or take extra shifts.

At the same time, most people remain unaware that their bodies are governed by a 24-hour biological clock and that they should take this into account when determining their daily schedules.

And without proper coordination with their bodies’ internal clocks, vital biological activities like growth, memory formation, decision-making, protection from infections and repair of body tissues – the latter of which largely takes place during sleep – can be sub-par or fail entirely.

Russell Foster, a professor of circadian neuroscience who is director of the Sleep and Circadian Neuroscience Institute (SCNi) and the head of the Nuffield Laboratory of Ophthalmology at the University of Oxford, discusses these issues in his book Life Time: The New Science of the Body Clock, and How It Can Revolutionise Your Sleep and Health.

In the book, he covers the importance of sleep and how humans can get better sleep, especially for the night shift workers and for those people who often travel through different time zones or otherwise have their patterns of sleep at night interrupted or disturbed.

“It’s the body clock or the circadian rhythms that provides this time structure for life. Part of the reason for writing Life Time is because I’m irritated by the incorrect headlines screaming that you must sleep eight hours or you must do this and that,” Foster said in a Zoom meeting with the Asia News Network. “One shoe size does not fit all. Some people can be perfectly happy with six hours, some only with 10-11 hours. We can identify how much sleep we need and then get that pattern of sleep that works best for us.”

Different people, different patterns

Foster’s thesis is that people need to embrace their own patterns of sleep because it makes them who they are. Doing so improves their sense of humour, their ability to empathise with others and to come up with wonderful solutions for complex problems.

He writes that, during sleep, important toxins are being cleared from the body and it can also consolidate the memory, so living out of sync with one’s body clock is not only disrupting one’s sleep but also leaving people more vulnerable to infections, cancers, obesity, type 2 diabetes, heart disease and mental illness.

“If you have massively destructive patterns of sleep during the middle-aged years there is an increased risk of dementia in later years. The quality of our day while we are still awake is defined by the quality of our sleep at night,” Foster said.

So how do you know if you’re not getting enough sleep? He says, first of all, you need to ask yourself questions like, are you functional during the day? Do you feel you’re working at your actual best? Do you need your alarm clock to wake you up or do you need somebody else to get you out of bed? Do you crave energy drinks or caffeine to keep you going? Do you need an afternoon nap? All of those things are telling people that they need to get more sleep.

However, Foster makes clear that he believes that a 20 minute nap in the afternoon is beneficial and can help people to be more productive during the second half of their day, but it becomes a problem if the nap goes longer or it takes place closer to bedtime.

Morning person? Night owl?

He adds that sleep is very flexible and dynamic in some sense and the waking-up stages have a lot of different possible patterns, durations and timings and these relates to a person’s “chronotype” which means whether you are a morning person, evening person or somewhere in between, because the three important sleep-wake timing drivers are genetics, hormone changes and exposure to light.

“Humans have this internal clock ticking away and for most of us it is slightly longer than 24 hours. So in the natural world what we need is to correct the slightly long clock and make it exactly 24 hours. The key factor of that in particular is morning light.

“We’re trying to work out how light regulates the internal clock and in the process, we discover that the eye is the organ of space and time. So people who’ve lost their eyes or have had terrible eye disease are not only visually blind but they are clock blind,” he said.

Sleep patterns do changes when you go away from the equator and not only natural light but also the artificial light from devices, lamps or street lights can affect human sleep.

Tips for night shift, jet lag, light levels

The importance of light explains why night shift workers body clocks adapt to the demands of working at night, but across all studies, 97 per cent of the individuals didn’t really adapt to the demands of working at night, which means that the problem that long-term night shift workers face is their sleep pressure is incredibly high after finishing the shift but the body clock says they can’t sleep during the day.

“The blackout curtains, the sound-proofing and having something easy to digest to suppress the stomach so they won’t wake up from hunger are all ways to enhance sleep in those situations,” Foster suggested.

Foster said that employers can improve their night shift workers’ condition by providing vigilance devices to stop crashes, offering appropriate food, high-frequency health checks, education on the topic and maybe even by chronotyping their workforce and making recommendations for sleep based on that.

“Try and match the body clock types of the individual to when they are expected to work. Now the business sector in the UK is taking this stuff seriously because they’ve realised that if they want a productive workforce and reduced illness, time loss and accidents, they have to take notice of this and where possible, take action,” Foster said.

These ideas also apply to jet lag, which is when people go across multiple time zones through airplane trips. He said people can also speed up recovery from jet lag by trying to impose an eating schedule similar to the one in the new time zone and that many people take melatonin to help them adjust, but Foster said it depends on the person, and it doesn’t work for him.

“Going west, expose yourself to light going east by avoiding morning light and seeking out afternoon light for the first four or five days in the new time zone,” he advised.

Many people have also experienced added fatigue as a result of Covid-19. During that experience, Foster said to stick to your regular bedtime, get morning light to set the body clock and do all of the things that enhance your sleep that you would do normally do and don’t get anxious over your illness, because a high level of anxiety will suppress your immune system and not allow it to realign as quickly it would normally.

He added that humans are just like all other mammals that have been studied under conditions of interrupted sleep.

“If you do wake up, stay relaxed and go back to sleep again. If it’s not working, immediately leave the bedroom and do something relaxing, listen to a piece of music, read your favourite book and then return to your sleeping space,” he said.

Foster has a lot of useful tips to get a better night’s sleep that include what activities people should do during the day, before bedtime.

For instance, people should get exposed to light in the morning as it’s a great way to set their natural clock. If you take a nap, make sure it’s not more than 20 minutes and not too close to bedtime. Exercise and try to do that in the morning and again later on, but not if it’s too close to bedtime, and everyone should have a regular eating pattern where the main meal of the day is in the morning, along with a lighter lunch and dinner.

Before bed, Foster said to reduce light levels and stop using electronic devices because it has an “alerting effect”. Short term use of sleep medications is alright, but long-term use is a problem. Avoid discussing stressful topics before bed and the bedroom itself ideally shouldn’t be too warm. Don’t make use of sleep monitoring technology because it’s unreliable and can generate huge anxiety, just try to establish regular sleep routines.

The future of sleep

Foster said he spent nearly 40 years working on the fundamental science of sleep and the circadian rhythm with discoveries of new focus receptors being one result and what he’s doing now is working with his colleagues to turn this knowledge into better pharmaceuticals with increased human benefit, including giving a sense of time back to those individuals who have lost their sight.

He’s also been involved in researching other drugs that increase the amplitude of the clock and help the elderly whose amplitude has decreased and also a drug that may be helpful for jet lag, but it is still in the research phase and they haven’t gotten their study results back yet.

“And I’ve also been thinking that if we can develop a drug that will stabilise this sleep-wake pattern problems for some people it would do a tremendous amount of good, and I think that’s what I’m going to be spending the last years of my productive life working on,” Foster said.