On the night of 25 October, the clocks go back one hour. Many people love this change – after all, “we get an extra hour of sleep”. And it’s true: the autumn clock change is much easier on the body than the spring one. Still, it doesn’t go entirely unnoticed. Let’s look at what happens and how you can help yourself.
Our day is run by three clocks: the internal biological (circadian) clock, the solar clock and the social clock – the times of work, school and meetings. We feel best when all three tick together.
The internal clock is set mainly by light, especially morning light. When we change the clock on the wall, the sun doesn’t move at all, but our internal clock keeps running on the old rhythm for a few more days. It’s like a short trip across a time zone – mild jet lag, just without the suitcase.
Not quite. A scientific review (2013) found that there is hardly any noticeable extra sleep on the night of the change. And over the following five working days, many people get up earlier than their internal clock would like, so across the week they may even end up sleeping less.
By the way, children and pets don’t look at clocks. If your little one used to wake up at 7:00, on Monday they’ll most likely be wide awake at 6:00 new time.
A large survey of around 55,000 people (2007) showed that in autumn, sleep and activity rhythms adjust fairly quickly. In spring it’s much harder, especially for night owls.
What fascinates me most is another finding from the same study: on days off, when people wake up without an alarm, their sleep follows dawn. As sunrise shifts, our waking time gently shifts with it. In autumn we return to winter (standard) time, which is closer to this natural rhythm – more light in the mornings. That’s why the American Academy of Sleep Medicine (2024) and other sleep science organisations recommend stopping the clock changes and keeping winter time permanently.
What happens to our mood?
After the clock change, evenings suddenly get dark an hour earlier. In Denmark, an analysis of more than 185,000 hospital contacts for depression (1995–2012) found that 11% more new depressive episodes were diagnosed after the autumn clock change. This increase faded within about 10 weeks.
This doesn’t mean everyone will feel worse in autumn. But it’s a good reminder: at this time of year, morning and daytime light is not a luxury but a necessity. If a low mood lasts longer than two weeks and gets in the way of everyday life, talk to your GP – it’s not a sign of weakness, just the shorter path to feeling better.
Before the clock change
1. Starting 4–5 evenings beforehand (from 21 October), go to bed 15–20 minutes later each evening. That way you’ll smoothly “travel” one hour over a few days. The same works for children.
2. On Saturday evening, go to bed at your usual time, and on Sunday get up at your usual time – by the new clock.
After the clock change
3. Get daylight as early in the morning as you can: even 10–15 minutes outdoors on a cloudy day gives you far more light than indoor lamps.
4. Breakfast, a little movement and talking to people in the morning are also signals to your internal clock that the day has begun.
5. Spend your lunch break outdoors. When evenings are darker, daylight becomes even more valuable.
6. In the evening, dim the lights and spend less time on screens. Keep your bedroom dark, quiet and cool – 16–20 °C.
7. If you feel very sleepy in the afternoon, take a short nap: no longer than 30 minutes and no later than 2 pm.
8. For the first 1–2 days, if you can, avoid scheduling your most important meetings. And in the evenings, don’t forget to wear something reflective – it gets dark earlier, and drivers are still getting used to it.
I’ll admit: even though I know it’s easier to prepare in advance, I’ve never actually done it myself. So if you don’t manage it – no worries. Two things matter most: your usual wake-up time and light in the morning.
The autumn clock change isn’t the enemy. It’s simply a reminder to give your body back a simple rhythm: light in the morning, darkness in the evening.
