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Clocks go forward

On 26 March, the EU Parliament voted that it is up to each individual country to decide if it wants to continue with the clock change twice a year or keep the same time all year round. Every country has two years in which to decide which time system they want to have in future.

”The changeover to summer time (daylight saving time) on the last Sunday in March was originally introduced primarily for financial reasons since it implies a saving of energy, although nowadays that has been questioned. There were no real medical reasons why summer time was introduced but nevertheless it does have some effects on our biology, health and behaviour. Summer time means we have one more hour of light in the evening when most people are off work and that in turn promotes more outdoor activities which is probably good for public health,” says Arne Lowden who is a sleep and stress researcher at the Stress Research Institute, Stockholm University.

Largest biological impact is on sleep
The largest biological effect of the seasonal clock change is on our sleep when we change from standard time to summer time. We “lose” one hour of sleep which leads to increased daytime sleepiness. It is harder for people to get up and it takes longer. It has also been shown that our sleep becomes more disrupted. This could be a reason why more road accidents happen during the week after the changeover to summer time

Increase in number of heart attacks
More heart attacks occur early in the morning than at other times. An increase in heart attacks during the week after the changeover to summer time has been observed by researchers in Sweden and in other countries. It has also been shown that “evening people” in particular (for example, youngsters with a late sleep phase) can react negatively to the changeover to summer time and it can take several weeks before their body clock has adjusted.

How you can alleviate the stress on your biological body clock:

  • Have a lie-in on the first Monday.
  • Sensitive people should move their clocks forward by 15 minutes per day for four days. (This could also be good for people who run stables, dairy farms etc.).
  • Be extra careful when out in traffic during the first week after the changeover.
  • Allow more time for putting children to bed.
  • Make use of the daylight for outdoor exercise.
  • Expose yourself to natural daylight in the morning to help your body clock adjust.