Optimal sleep requirement differs in every person, says new findings

Professor Russell Foster of the University of Oxford, emphasises that sleeping patterns vary from person to person.

Optimal sleep requirement differs in every person, says new findings

Russell Foster presents a comprehensive manifesto for living in harmony with our body clocks

Against the popular myth about sleep, Professor Russell Foster, neuroscientist from University of Oxford believes that there is a widespread social pressure to get eight hours of sleep but “one size doesn’t fit all. 

His findings are published in his book,  LifeTime: The New Science of the Body Clock, and How It Can Revolutionise Your Sleep and Health. Prof Foster emphasises that sleeping patterns vary from person to person. In a candid interaction with The Statesman, Prof. Foster shared deeper insights about sleep and how important it is for our body. 

Russell Foster is a British professor of circadian neuroscience, the Director of the Nuffield Laboratory of Ophthalmology and the Head of the Sleep and Circadian Neuroscience Institute. He is also a Nicholas Kurti Senior Fellow at Brasenose College at the University of Oxford.


 Is the sleep pattern different among people belonging to different cultures?

This is a very important point and we must understand how sleep is different for everyone. A better way of putting that would be “One shoe size doesn’t fit all”. There is a widespread social pressure to get the 8 hour sleep and it is widely believed that if we are not getting sleep for that many hours, we are committing a crime on our health. An optimum sleep is anything between 6 to 10 hours and it depends from person to person.

 Everyone should ask a few questions to know if we are getting enough sleep; Do you need an alarm clock to wake up; Do you need a longer time to wake up and be active; Do you feel sleepy during the day? There is no defined pattern in which sleep works. The natural factors that we are exposed to decide our sleep. We all have our own biological factors, we are all very different from each other and require different amounts of sleep. Our sleep patterns can very much be influenced by cultures. 

Professor Russell Foster, neuroscientist from University of Oxford
Professor Russell Foster


In many cultures, there is a practice of sleeping during the day, how does this practice impact our overall sleep pattern?

 In countries, where the day-time temperature is hot, there is a common practice of siesta, or a nap during the day. This makes a lot of “biological sense”. The daily life routine is designed in such a way that people sleep during the day and remain awake during late hours of the day. It works for them. However, when we take a nap, we must ensure that we do not extend it beyond 20 minutes, as it results in delaying our sleep at night. A 20 minute nap during the day is considered healthy and helps us remain alert and active during the later part of the day. We should not worry much about a short nap, many people take a small nap. In fact, there are many businesses around the world, who provide sleeping pods for their employees. However, you must be aware of the fact that if you require a nap during the day, it means you are not getting a full set of sleep at night. We should not be very rigid about it, and be flexible. The important point to note is that nap time is not closer to the night bed-time.

 Does the geographical area impact sleep?

 Yes, it does.  Suppose you are away from the Equator, northward or southward, the length of the day would change. At the Equator, it is almost 12 hours of daylight and 12 hours of darkness. At the North or South pole, you would get either complete darkness or complete light during winter and summer respectively. In Scandinavian countries, I have seen families, who have created a room that has light boxes in their homes to expose themselves to light during the dark months. 

Exposure to light is as important to experiencing darkness, for a perfect sleep pattern. Similarly, during the winter months sleep tends to increase and in summer months, sleep tends to decrease. Human body is very sensitive to light and the sleep clock works in conjunction with the light. This is the reason, if you look at the mobile screen before sleeping, the screen light shifts the clock and delays the onset of sleep. Smartphones and other devices are alerting the brain and disrupting our sleep pattern. This is the reason, to get proper sleep, it is also recommended to sleep in a dark room that doesn’t have bright street-light seeping in.

Over-thinkers and people with uncontrolled thoughts have sleeping issues. How do you explain this?

In most cases people do not have a sleep problem, they have an anxiety problem.I must stress on the need to relax one’s mind before going to sleep. One can try to read, listen to soothing music or relax through breathing exercise. It is very important to experience “mindfulness”. We live a ferociously hectic life and it is crucial to get out of our routines to experience effective sleep.

Some tips for experiencing better sleep and a relaxed daytime

  • Get ‘morning light’. It is very important to set our sleep-clock. 
  • If you nap, do not do it closer to bed-time
  • It is important to exercise, but don’t do it in late evenings. It would raise the core-body temperature and one of the factors to get proper sleep during the night is for the core body temperature to lower.
  • Avoid heavy meals at night. 
  • Reduce the light in the room, at least 30 minutes before bedtime
  • Stop using electronic devices and gadgets like smartphones, e-book readers, laptops etc. as they would have an ‘alerting effect’ on the mind.
  • Avoid sedatives and sleeping pills. Even your doctor would advise for a short term use, but if you are taking it for a long duration, it would impact the sleeping pattern.
  • Avoid important discussions with your partner around bedtime. If you stay away from your family or friends, avoid late night telephone calls. 
  • Taking a shower or bath before bed, helps in sleep
  • Ensure that your bedroom is not too warm
  • The bedroom must be quite and if it’s not, try using ‘white-noise’
  • If the room is not dark, try using dark shades and curtains
  • Do not take sleep-apps seriously. They are profoundly inaccurate!
  • Try to go to bed and wake at the same time
  • Ensure your bed is very comfortable