Society mainly supports A-persons (early risers) and working 9 to 5. Being a B-person (late riser) in an 9 to 5 society entails a great deal of social jetlag, which has a negative affect on health, education and careers. The majority of people are B-persons, so educational institutions and workplaces should be arranged in such a way to support B-persons as well.

A-persons have traditionally dominated the social set-up. They have created schools that start at 8 am and workplaces where managers reward the early risers. They have instilled an attitude in us that good people get up early. They have made B-persons feel guilt and shame if they do not arrive early. A-persons prefer to go to bed early and get up early. A-persons often sleep really well on workdays as society primarily supports a 9 to5 workday. A-persons wake up early every day – even on their days off.

B-persons prefer to go to bed later and get up later. B-persons are often not tired at 10 pm. B-persons go to bed late and, in order to fit in to the 9 to 5 society, they wake to the sound of an alarm clock. This means that B-persons accumulate a huge sleep deficit on workdays, and so sleep more on their days off.

A circadian rhythm is not something you choose. It’s something you’re born with.

Chronobiology is the study of humans’ internal clock; circadian rhythms. A circadian rhythm is all about when humans prefer to be awake and when they prefer to sleep. Professor Till Roenneberg, a leading researcher in chronobiology at Ludwig Maximilian University of Munich, has mapped the circadian rhythms of more than 220,000 people. The distribution of circadian rhythms (chronotypes) ranges from extremely early types (early chronotypes) to extremely late types (late chronotypes), just as human height varies between short and tall. An A-person may, for example, be awake from 6 am–10 pm and have most energy in the morning. B-persons, on the other hand, have most energy in the afternoon and evening, and may, for example, be awake from 9 am–1 am.

Health policy – a later start can reduce the amount of social jetlag

The difference between biological time (internal clock) and social time (school and work hours) is called social jetlag. The 9 to 5 society sets B-persons up for poorer health, as B-persons experience greater social jetlag. If there is a five-hour difference between when you get up on school/work days and when you get up on days off, you have five hours’ social jetlag – and it is in this category that we find 60 per cent of smokers. By comparison, ten percent of smokers are found in the section of the population that does not experience social jetlag. Research shows that for every hour of social jetlag, the risk of obesity increases by 33 per cent. Our society is arranged in such a way that the sleep of 80 per cent of the population is interrupted by an alarm clock.

  • It would be advisable to reduce the amount of social jetlag by adjusting the time that schools and workplaces start to human chronotypes.
  • It would be advisable to abandon the application of summer time, as it contributes to increased social jetlag in the population.

Education policy – A later start allows pupils and students to sleep more and get higher grades

School discriminates against B-persons. Research shows that almost all teenagers are B-persons. An 8 am start is in the middle of the biological night of young people, and B-persons receive poorer grades than A-persons if exams take place early in the day. Only when exams take place in the early afternoon are A-persons and B-persons competing on an equal basis. Research shows that a later start leads to more sleep for pupils/students and higher grades as a result.

  • A start time of 9 am is recommended for 0–6th grade, and a start time of 10 am is recommended from 7th grade and up.

Labour market policy – Adapt working hours to circadian rhythms and increase productivity

Research shows that managers tend to favour A-persons, who arrive early at the office. The fact alone that someone arrives at the office early increases their value. Those who arrive later are regarded by the manager as less conscientious. Managers who are B-persons themselves are less likely to judge employees who prefer a later start.

In the knowledge society, it is common sense, both from a human and an economic point of view, to match a person’s work hours to his or her biological rhythm. We need a paradigm shift away from the classic 8–5 work hours, to individuals having a greater say about their work hours. This will result in higher productivity, healthier employees and a reduction in healthcare costs.

In the 20th century, the unions fought for the right to 8 hours of work, 8 hours of sleep and 8 hours of leisure time. In the 21st century, we should fight for the right to work at the right time of the day. Research shows, for example, that it has greater health implications for A-persons to work at night than it does B-persons. Give A-persons A-person work hours and B-persons B-person work hours. Being able to control one’s own time will increase both the quality of life and productivity of the individual.

  • There is an untapped productivity potential in giving A-persons A-person work hours and B-persons B-person work hours.

Traffic policy – A later start for B-persons may solve infrastructure issues

We have an infrastructure issue four hours a day, as we use the roads at the same time in the morning when we go to work, and in the afternoon when we go home from work. Different start times will help solve the infrastructure issue in towns and cities. If B-persons start after 10 am, the traffic will be spread out over a longer period of time, both on the roads and cycle paths in the towns and cities. This would mean less idle running and lower CO2 emissions, as well as a shorter travel time for individuals.

There are great savings to be made.