On the last weekend of March, most Western countries set their clocks one hour forward. This time change (Daylight saving time) aims to reduce global energy consumption by matching working hours with daylight hours.
To take maximum advantage of daylight hours, clocks go forward one hour in spring and are put back one hour in fall to revert to standard time.
This measure was taken for the first time during the First World War in order to save fuel, although the idea had been suggested by Benjamin Franklin in 1784 as a measure to save on consumption of wax and candles. Then in 1973, industrialized countries make the time change again during the oil crisis.
The time change in the world
About 70 countries around the world switch to Daylight Saving Time and revert to standard time.
In Europe, it is a deeply rooted custom in almost all countries except Belarus and the European part of Russia.
The same is true in North America where the US (except Arizona and Hawaii states), Canada and Mexico (except in Sonora) change the time between summer and winter.
In Latin America there is no uniformity regarding time change. Paraguay, Uruguay and southern Brazil do change the hour every year while other countries have changed the hour at one point.
In Africa the only countries that change time are Namibia, Libya, Morocco and part of Western Sahara; however, other african countries have never done.
In Asia, Turkey, Iraq, Azerbaiyan, Israel, Palestine, Syria, Lebanon and Jordan observe the Daylight Saving Time. South Korea, China and Malaysia have changed the time on occasion, but currently do not.
Time change: How does it affect us?
In health terms, changing time has a “minimal” impact on the body, although sleep disorders of people who usually have trouble sleeping may worsen.
We should remember that currently 45% of the world’s population has trouble sleeping so the time change is an issue that every year raises more controversy.
Generally, the time change can generate “light” sleep disturbances and mood in people who do not suffer from sleep problems. During the first days, changing time can increase fatigue and irritability and cause headaches and lack of concentration.
These problems usually disappear within three to four days.
Children and people older than 50 years are the population groups most sensitive to the time change because they usually have regular sleep schedule. On the one hand, school-age children may have difficulty waking up. On the other hand, those older than 50 (who often have previous problems falling asleep and usually wake up early) may take much longer to adapt to the new timetable.
Tips to minimize the effects of the time change on sleep.
-Going to bed a little earlier three or four days before the time change,
-Trying not to nap for a few days.
-Go to a doctor if any significant sleep or mood alterations occur.
A controversial measure
Although in the case of Europe a European Directive (European Directive 2000/84) regulates the time change in the EU countries with the aim of saving energy, some social groups in various countries reject the time changes and demand that timetable to remain stable throughout the year.