Should daylight saving be abolished?

Anjana Ahuja March 12, 2025 Changing the clocks twice a year does not extend the light available to us.

In the UK, it is nearly time for the March magic of “springing forward”, when the clocks skip ahead an hour and the endless winter nights give way to the promise of long, light-filled summer evenings. Daylight Saving Time began last week in most states in the US and British Summer Time will come into force at the end of this month.

Many researchers, however, regard the stark time shift as misguided rather than magical. Not only do we lose an hour of sleep, leaving us more prone to the mishaps that beset the fatigued, but it messes long-term with the light cues that regulate our body clocks. It deprives us of the morning light that gets us going and bathes us in extended evening light, which disrupts sleep.

In October, the British Sleep Society called for daylight saving to be scrapped and for Standard Time (equivalent to Greenwich Mean Time) to run all year, arguing that “the available scientific evidence [shows] that circadian and sleep health are affected negatively by enforced changes of clock time, especially in a forward direction, and positively by the availability of natural daylight during the morning.”

Given what we know today about body rhythms and the effect of light on human health, it is probably time to abolish the twice-yearly switch. But it is not a simple policy nut to crack: the spring jolt across time zones still offers alluring connotations of balmy summer evenings — plus the tempting economic prospect of punters staying out and spending well into the night.

Germany was the first country to introduce daylight saving in 1916, with Britain following suit the same year. The wartime rationale was that brighter evenings reduced the demand for coal lighting. Today, according to the Royal Museums Greenwich, around 70 countries follow the practice, mainly in Europe and North America. Geography matters: Iceland, Belarus and Russia stay on their respective time zones all year. Equatorial countries, with about 10-12 hours of daylight all year round, do not need daylight saving.

But changing the clocks twice a year does not in any way extend the light available to us, points out Eva Winnebeck, who researches chronobiology and sleep at the University of Surrey and co-authored October’s statement calling for Standard Time to run all year round. “It’s not about removing long, beautiful summer evenings,” she insists, saying those would happen anyway. Rather, daylight saving is a societal decision to artificially shift light away from the morning and add it on to the end of the day.

That is damaging, she explains, because “morning light is the big signal” for our body clocks, which regulate everything from our sleep/wake cycles and mood to gene expression, hormones and metabolism. When it comes to body clocks, humans are a relatively sluggish species, with adolescents particularly vulnerable to circadian delays.

The British Sleep Society cites studies linking the springtime clock change to such unwelcome outcomes as a rise in heart attacks and stroke, and a drop in performance and productivity, often via its damaging effect on sleep. One University of Kentucky researcher has even advised investors to be wary of making big decisions when the clocks change. While Winnebeck cautions that teasing out any causal links is difficult, another circumstantial piece of evidence is the “western edge” effect, where people on the western fringes of time zones who see later sunrises and sunsets report slightly less sleep than their eastern counterparts.

The British Sleep Society now shares the view of the American Academy of Sleep Medicine that daylight saving should end, with permanent standard time operating all year round. Both organisations advocate even more strongly against countries shifting permanently to the summer clock. The US sunshine protection bill, co-sponsored by now secretary of state Marco Rubio, aims to make Daylight Saving Time the all-year norm.

Interestingly, the UK, Russia and Portugal previously tried exactly that but dropped it after a few years. During the second world war, the UK also dabbled temporarily with British Double Summer Time, putting the clocks two hours ahead of GMT in summer and one hour in winter.

Those episodes illustrate the strange paradox at the heart of national timekeeping: every aspect of our lives is choreographed by the precise ticking of the clock but the way we collectively manipulate national time — with one-hour shifts here and there for some countries and US states and not others — seems almost absurdly arbitrary. We could do worse than see the light.

Posted: to Wealth Management News on Thu, Mar 13, 2025
Updated: Thu, Mar 13, 2025