When the Clocks Go Back: A Simple Plan for the Week

The clocks go back this weekend. In the UK and most of Europe the change comes in the early hours of Sunday 25 October, and most of the US and Canada follow a week later, on 1 November. On paper you get an extra hour in bed. The people who notice the change most are early risers and parents of small children, whose mornings are set by a body clock rather than an alarm. That clock is still on summer time. A toddler who woke at 6 a.m. last week will now wake at what the clock calls 5 a.m.

Autumn is the gentler of the two changes, and most people settle within a week. A few small adjustments to your routine make that week easier.

Why the Extra Hour Often Goes Missing

You might expect the autumn change to bring a free lie-in. When Yvonne Harrison reviewed the research on clock changes and sleep, she found that many people don’t actually get the extra hour. They wake earlier than they meant to, and they wake more often during the night. Sleep can take up to a week to settle, and longer for people who already sleep short hours or who are natural early birds.

Harrison, Y. (2013). “The impact of daylight saving time on sleep and related behaviours.” Sleep Medicine Reviews, 17(4), 285-292.

Your internal clock hasn’t moved, and that explains most of it. At 6 a.m. on the new time your body thinks it’s 7, so if you normally wake by yourself at 6, you’ll now be awake at 5. Evenings shift the same way. At 9 p.m. it feels like 10, and the yawning starts an hour before it usually would.

Autumn Is the Easier Direction

The spring change, when an hour is taken away, is the one behind the worrying headlines. A 2019 meta-analysis pooled studies of heart attacks around the switch and found that the risk rose slightly, by about 5%, in the week after the clocks went forward. After the autumn change there was no significant increase.

Manfredini, R. et al. (2019). “Daylight Saving Time and Acute Myocardial Infarction: A Meta-Analysis.” Journal of Clinical Medicine, 8(3), 404.

The direction of travel matters for another reason. Going back returns you to standard time, which sits closer to the sun. Under summer time the clock runs an hour ahead of daylight, so work and school start earlier, relative to sunrise, than most bodies would choose. The chronobiologist Till Roenneberg and his colleagues call the gap between body time and the timetable “social jetlag”, and they argue that summer time makes it bigger. In their view, staying on standard time all year would suit human biology best.

Roenneberg, T., Winnebeck, E.C. & Klerman, E.B. (2019). “Daylight Saving Time and Artificial Time Zones – A Battle Between Biological and Social Times.” Frontiers in Physiology, 10, 944.

The American Academy of Sleep Medicine took the same line in 2020, calling for an end to seasonal clock changes in favour of permanent standard time. Governments have debated scrapping the switch for years. So far the clocks keep changing.

Rishi, M.A. et al. (2020). “Daylight saving time: an American Academy of Sleep Medicine position statement.” Journal of Clinical Sleep Medicine, 16(10), 1781-1784.

A Plan for the Week

On Sunday and Monday, get outside in daylight within an hour or so of your usual wake-up time on the new clock. Daylight is the strongest signal your body clock receives, and getting it at the new time helps the rhythm settle there. Keep your wake-up time the same every day that week, even after a short night, and try to stay up until close to your normal bedtime instead of giving in to the early yawns.

If you wake at 5 a.m. and can’t drift off again, don’t lie there fighting it. Get up, keep the lights low and do something quiet until your normal morning starts. Bright light that early tells your body the day has begun, which holds it on the old schedule. For most people the early waking fades within the week.

Small children are harder, since there’s no talking a three-year-old into sleeping until seven. Move their bedtime in 15-minute steps over a few days rather than a full hour at once. In North America you have a head start: from about Wednesday, put them to bed 15 minutes later each night, and by Sunday they’ll already be on the new time. In Europe, where the change is tomorrow, start on Sunday evening with a bedtime slightly earlier than usual by the new clock, then work back to the normal time over the next few nights. Expect a couple of early mornings either way.

Darker afternoons make a 4 p.m. coffee tempting. Keep caffeine to the morning this week, while your sleep is still unsettled. And since evenings now get dark early, move some of your outdoor time to the middle of the day. If you leave work after sunset, a walk at lunch may be the only daylight you see on a weekday.

Lamplit’s sleep log is a simple way to see how long your own adjustment takes. It asks for bed time, wake time and how well you slept, with optional tags such as caffeine or a late screen, and it’s free. Log last night’s sleep today, so you have at least one night from before the change, then keep going through the following week. In North America you can start a full week ahead. Next weekend, scroll back through your sleep history and count the mornings it took before your wake time stopped drifting early.

Log last night’s sleep in Lamplit and see how many days the clock change takes to wear off. It’s free.