Some people are bright and breezy first thing in a morning (hard to believe if you are an owl of course) whilst others don’t come to life until later in the day.
Research by biologists in Germany found that people whose performance peaks in the morning are more proactive than people who are at their best in the evening. (There may be an element of puritan work ethic in this of course)
They tend to get better grades in school, and have better job opportunities. They also anticipate problems and minimise them. Their proactive trait is what leads to better job performance, greater career success and higher wages.
Evening people have some advantages: they tend to be smarter and more creative than morning types, have a better sense of humour, and are more outgoing. Unfortunately they are out of synch with typical corporate schedules according to Professor Christopher Randler at the University of Heidelberg.
If you find yourself waking up at the same time every day, even the weekends, then you are probably an early bird. On the other hand if you like to take advantage of your weekend and have a lie-in – the scientists found a 2 hour difference on average – then you are probably an owl.
It seems more people under 30 are evening types; from 30 to 50 it’s evenly split; and after 50 most people are morning types. You can change your “chronotype”, 50% of which is due to genetics, by changing your sleep pattern but it only works for half those who try and only a small shift of an hour or so.
Source: HBR July/August 2010
Updated 13 November 2010: Everyone has probably heard about Winter blues, Seasonal Affective Disorder (SAD), where lack of sunlight or daylight makes us feel depressed (and may contribute to the high suicide rates in some Nordic countries which enjoy long Summer days followed by long Winter nights).
Experts now say that we should have exposure to bright daylight throughout the year. This is because daylight sets our body clocks and if we don’t get enough at the right time of day our body clock gets out of synch. That makes us feel tired and may influence our mood and concentration so that we rely on stimulants like coffee to keep us going.
This phenomenon has been called social jet lag, by Professor Till Roenneberg at the University of Munich, and it occurs because we evolved to live by natural patterns of daylight and night.
Bright lights in the morning stimulate the production of adrenaline, cortisol, and serotonin, which help us keep awake and feel mentally alert. When light fades the pineal gland produces melatonin and adenosine which make us sleepy.
However with modern work patterns we may wake up in the dark, go to work in artificial daylight, then as it grows dark in the evenings switch on bright lights and probably spend time in a brightly lit bathroom before we got to bed. This has the same effect as having a cup of coffee. So too much time in the wrong kind of light at the wrong time of day.
It’s estimated that 3 out of 4 people need an alarm clock to get up in the morning (I’m definitely an owl and I need two alarm clocks if I am going out to work) as their body clock is behind the real time and they are working at times which may not be biologically right for them.
The body clock also sets our metabolism and kidney functions and if yours isn’t in synch with real time you are more likely to use coffee or cigarettes to keep you awake and alcohol to help you sleep. You also run the risk of being overweight as you will eat at the wrong body clock times.
One study found that having lower levels of melatonin encourages cancer growth. Interestingly melatonin is used as a drug to help travellers overcome jet lag and I learned is also mainly produced between 2300 and 0300 when you are asleep. So owls like me going to bed in the early hours risk reducing their melatonin production. Knowing this helped me to make an extra effort to get to bed before midnight!
NB And none of this relates directly to how much sleep you might be getting – see “Are you getting enough Sleep?”
The problem is that artificial light is not bright enough and is only about 5% of the light intensity on a cloudy day. The best light is the brilliant blue sky and white sunlight which keeps us alert and prepares us for sleep. I remember the first time I went to Finland in the Summer and how wonderful it was seeing the sky so bright and the air seemed so much fresher.
The Health Protection Agency in the UK is studying the effect of light on people in care homes and hospital to se if it can aid recovery, or even help them sleep better, and improve staff energy levels. Working without natural daylight is a definite no-no for many people and having sight of green grass and tress is a definite stress-reducer.
The challenge is not so much having bright light in the morning – at least 20 minutes a day is considered necessary to maintain out body clock’s accuracy – but having lower light levels in the evening whilst still being able to work. Scrapping British Summer Time would make the problem worse as it would give is more light at the end of the day all the year round.
Professor Roenneberg suggests that if you suffer from social jet lag you could try wearing sunglasses from 1600 onwards. A good excuse for looking cool in the office? Source: Daily Mail 9 November 2010
Great pull-out section in The Times (8 December 2010) “Understanding Sleep”. Everything from fatigue at work, body clocks, sleep problems to medication. Well worth a read!
Updated 16 December 2010: Scientists claim to have discovered a chemical that can wind back your body clock so that you don’t suffer jet lag (reported in PLoS Biology).
A drug called “longdaysin” can slow down the body clock for up to 12 hours which means it may be possible to calibrate the dose so you can take just the right amount to offset the number of hours that your body needs to adjust. Obviously this would be a boon to frequent flyers and shift workers if it works on humans.
So far the compound – which was found after screening more than 100,000 potential ones – has only been tried on zebra fish which had their biological clock reset by 10 hours. They reportedly suffered no ill-effects and their body clock returned to normal when the treatment wore off.