Time change: effects on health

General information

Unfortunately, we find the seasonal time change particularly difficult at the beginning of the year. Although the daylight phase is noticeably shifted further into the day, which certainly has a positive effect on our enjoyment of life, the postponed hour literally throws our biorhythm out of sync. On the days following the time change in particular, time often flies by so quickly that we spend days running after the lost hour. Tiredness and depression are among the most common consequences. However, people have very different ways of adapting to the change: What some people snap out of within a few days can take several weeks for more sensitive people.

Studies have shown that setting the clock back in the fall causes us fewer problems. The 25-hour Sunday following the changeover is often perceived as particularly long and relaxing. Although the biorhythm is also disrupted here, many people have a positive perception of the summer-autumn changeover, as they are virtually given an hour as a gift. All the more reason to miss the stolen hour in spring when the clock is set forward and an hour simply falls by the wayside.

What is certain is that the sleep-wake rhythm of humans and animals is thrown out of sync by the time change and this has various health effects:

Not all studies on the subject of time changes and health show such clear correlations. However, the bottom line seems to be that adapting to the time change does have an impact on our well-being.

Chronobiology - of owls and larks

Chronobiology deals with biological rhythms and the biological zeitgebers that make these rhythms possible.
In humans, chronobiology distinguishes between two chronotypes, which are genetically determined and help determine our internal clock: on the one hand, the late chronotype, the'owl' - those who tend to go to bed late and get up late accordingly - and on the other hand, the early chronotype, the'lark' - i.e. the early risers who normally also go to bed early.

The time change in spring, which 'steals' an hour from us, is a particular problem for the owls with long-lasting after-effects, as it corresponds even less to their internal clock than that of the larks. The consequences are comparable to those of jet lag, because in principle exactly the same thing happens as if you were to fly to a country with a different time zone.

Which chronotype are you? Questionnaire from the Ludwig Maximilian University of Munich

Effects on the sleep rhythm

Some people look forward to the time change and others don't know what to do with themselves. If you're a workaholic or a late riser, you can count yourself lucky when the time changes to winter time, because this day is 25 hours long. Now you can finally do the things you have always put off for time reasons or use this hour to sleep longer.

So it's only natural that we should look forward to this long day. However, many people have serious problems with the time change because it disrupts their natural sleep rhythm. The body is thrown completely out of sync when it suddenly gets dark earlier. If you don't keep to your sleep rhythm, you lose concentration and can even fall ill. Unfortunately, it is not so easy to adjust to a new rhythm overnight. Even if the change is only one hour, sooner or later you will notice the effects in the short term. These often affect the psyche and many bodily functions such as circulation, metabolism and well-being. The internal clock determines what our body and brain do and when, and if you mess this up, problems can arise. It is normally based on the position of the sun, the seasons and the body's own needs. As soon as it is dark, the messenger substance melatonin is released in greater quantities, which is why we become tired. When the hormone is at its peak, we are in deep sleep. When it gets light in the morning, the melatonin level drops again and our body wakes up again.

To prepare yourself and your body well for this change, you should try to slowly adapt your routine to the new time. When switching to winter time, you can try to go to bed a little earlier each evening so that your sleep rhythm can adjust well. But the rest of your evening routines, such as dinner, sporting activities or watching TV on the couch, should also take place a little earlier than usual. A walk in the evening is helpful to get some fresh air and calm down after work, as this helps you to fall asleep better afterwards.

After the changeover, it is also important not to rush through the first few days. You should take a more relaxed approach to the day and not schedule appointments for the early morning or evening. This makes it a little easier for the body to cope with the new time.

Time change and taking medication

As every year, the time change is coming up in March and October, and in addition to the question of which direction it will now be shifted, some people are also wondering what the time is for taking medication, especially the pill. First of all, the clock is set one hour forward when the changeover to summer time takes place. When switching to winter time, which is also known as "standard time", the clock is set back one hour accordingly. With many medications, a certain time rhythm should often be adhered to in order not to interrupt the effect. However, with a time change, it is sometimes difficult to stick to the exact time, as the medication should actually be taken an hour earlier or later.

With the contraceptive pill, the rhythm should normally be 24 hours. However, this can easily be extended for micropills, which are combination pills containing female and male hormones, so that they should be taken within twelve hours of the normal time. However, if this twelve-hour period is exceeded, reliable protection is no longer guaranteed. An additional contraceptive should then be used.

You should be a little more careful when postponing the time you take a progestogen-only mini-pill and make sure that you do not exceed the normal intake time by 90 minutes to ensure reliable protection against pregnancy. So if you usually take them at eight o'clock, it doesn't matter when the time changes because there is only a one-hour difference. After one or two days, the body will have got used to the new time of taking the pill and the hormone level will be the same as before the time change.