When Do The Clocks Change In 2020 – And How Does It Affect Us?

The clocks go back an hour this weekend – how is that time again? ⏰

For most people, the clocks changing in March and October every year cause little more than the inconvenience of having to change your watch. Or does it?

Various studies have shown the 60-minute difference actually has a quantifiable impact, and has even lead to campaigns calling for it to be scrapped completely – in 2011, MP Rebecca Harris floated a bill calling for year-round daylight savings.

We didn’t always have this system in the UK – it was only introduced during the Second World War to help munitions factories maximise productivity and allow people to get home safely before the blackout. So, now you know.

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David Prerau, author of ‘Saving the Daylight: Why We Put the Clocks Forward’ agrees this isn’t just about an hour in bed: ”[Daylight Savings] affect everything from Mid-East terrorism to the attendance at London music halls, voter turnout to street crime, gardening to the profits of radio stations.”

So if the clocks changing really is such a big deal news, what impact can we really expect to feel when they go back this weekend?

1. It will disrupt our sleep cycle.

For a nation that is already sleep deprived (a study found that on average Brits are missing out an entire’s night sleep per week) having our alarm thrown out of whack by an hour can make matters even worse.

Obviously gaining an hour in October can feel glorious, but it still can make our internal circadian rhythm a little confused when we wake up expecting it to be an hour earlier or later than it is. In order to mitigate the effects, try going to bed 30 minutes earlier in the days before.

2. It can make hormonal skin worse.

It might not feel like the most life changing of issues, but having a spell of bad skin can make anyone feel a little under the weather and Dr Firas Al-Niaimi, group medical director at sk:n clinics, says that the clocks can make this worse: “The clocks going back can affect our hormones, mainly because of the change in our sleep patterns, which can mean an increase in acne.” (For those who are already suffering, of course.)

“It’s important to keep up a thorough skincare routine before bed, and relax before you go to sleep, so your sleep isn’t interrupted and skin cells can repair overnight,” she adds.

3. It increases the likelihood of having a heart attack.

It sounds drastic, but it has been shown in studies of 43,000 patient records that after spring daylight savings time, there is an increase in the incidence of heart attacks, and in the autumn months, a decrease.

Researchers say the clocks don’t cause an overall greater incidence of this in a population, but it definitely has a marked impact short term, with the Monday following spring time change seeing a 24% increase in heart attack admissions and the Tuesday after autumn shift seeing a 21% reduction.

4. It increases your stroke risk.

As if a heart attack wasn’t enough to worry about, a study from Finland that looked at nationwide patient records from 2004-2013 also showed the clocks changing also increases your risk of having a stroke, because your circadian rhythm is disrupted.

Similarly to heart attacks they found incidence was increased during the first two days after the transition, but difference was “diluted” when observing the whole week of hospital admissions. Women were disproportionately affected.

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5. It causes more road accidents.

The impact on road accidents has been well documented over the years, and in fact was one of the major conclusions from a three-year trial (1968-1971) by the British government where clocks were not rolled back, and there was a “serious reduction” in the number of people killed or seriously injured on the roads because they were lighter for longer in the evenings.

Then again in 1996, a study published in New England Journal of Medicine confirmed this finding by showing an 8% increase in motor vehicle accidents on the Monday following the clocks changing. A 2001 study from Johns Hopkins and Stanford universities also showed an increase on the Monday.

They found if a year-round alteration to BST was made, 160 fewer people would have been killed, 650 fewer seriously injured and 2,060 fewer motorists and pedestrians would have sustained any form of injury altogether.

6. It can put us in a bad mood.

No this isn’t just because you are grumpy at having to get out of bed or sulking because you forgot the clocks were changing, in fact the disruption actually has a discernible impact on our moods.

In a study of a group of legal judges from 2016, researchers proposed that sleep deprivation increased the severity of their sentences they were handing out to criminals. Taking advantage of the natural shift to daylight saving time in the spring, they compared this period to the archives of sentences and found that judges did dole out longer sentences when sleep deprived.

7. It costs us more money.

And if your health (and general ability to be nice) weren’t enough to make you annoyed about the clocks changing, it is going to hit you where it hurts most – your pocket. A report from the Policy Studies Institute (from 1990) estimated that consumers could save £260m a year on electricity bills if the clocks didn’t change (and just think about how much that would be thirty years later).

Researchers at the University of Cambridge also found that an extra daily hour of sunlight in winter could save £485m each year, as people would use less electricity and heating. That has the same effect as eliminating the carbon emissions of 70,000 people.