Short Wave - Should Daylight Saving Time Be Permanent?

Episode Date: November 3, 2022

Correspondent Allison Aubrey talks to host Emily Kwong about the pros and cons of adopting permanent Daylight Saving Time or year-round Standard Time.See pcm.adswizz.com for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences.NPR Privacy Policy

Hey folks, Aaron Scott here. So daylight savings time ends this weekend, which means we get an extra hour of sleep this Sunday at 2 a.m. But, but, but, but, but it is an hour that we lost earlier in the year in March. And of course, people have strong feelings about this, whether we should change the time at all and in which direction. The U.S. government has even taken up the issue. And a big question in this daylight savings debate is how it affects people's health. So we talked to health correspondent Alison Aubrey this past spring to get some answers. You're listening to Shortwave from NPR. So much of life is about trade-offs. You give a little, you get a little. And we've got a trade-off today that I sure have thoughts on.

Maybe you do too. What about you, Alison Aubrey? Yes, I've got some thoughts. We're talking, dear listeners, about the twice yearly changing of the clocks. spring forward when daylight saving time begins and fall backward when it ends. It may not sound like a big deal, but it turns out our bodies are a lot more sensitive to time than most of us ever realized. And back in 2015, I spoke to this circadian scientist named Fred Turrick at Northwestern University about it. Yeah, let's listen to some of that.

We've known for a long time about the master clock in our brains that synchronizes our body to the 24-hour light-dark cycle. But in recent years, scientists have made a pretty cool discovery. It turns out that we have different clocks in every organ. Yes, there are clocks in all the cells of your body. Wow, it's kind of stunning. Yes, that is a discovery that's literally surprised us, I must say. Turek says, think of all these clocks in our bodies as instruments or players in an orchestra. The idea that the heart has a clock.

Think of it as a drum. And the kidneys? The kidneys have a clock. Two clocks. One in each kidney. Maybe they're the horns. Then there's the pancreas. Oh, yes.

The pancreas has a clock. That's the flute. Now, the master clock in our brains is like the symphony conductor, keeping all of the players in sync. Once the conductor comes on, everybody's in synchrony, and it sounds beautiful. The idea that your body is functionally normally, when everybody's in synchrony with the master conductor in your brain. You're sleeping well, eating regularly, and feeling good.

But what if the clocks get out of sync? It sounds so bad, right? Ah, the clash, the cacophony. Yeah, cacophony, that's how I feel, daylight saving time. It's kind of like, ooh, you're just all over the place. And that really takes us to today's debate that if we do away with switching the clock twice a year, which many scientists say would be a good idea, the debate is which one is better, having extra sunlight in the morning or the evening.

Yeah. And in a rare bipartisan moment, the U.S. Senate voted unanimously earlier this month to make daylight saving time permanent. Some states have already opted out of the twice annual clock change. Most of Arizona and the state of Hawaii, for instance, remain on standard time year round. For any change to permanently do away with the clocks changing around the country, though, the House of Representatives would need to pass the measure, too. And while this year the bill is not likely. to become law. More than ever, the discussions seem to be out there. So today on the show,

to keep or not to keep, or what to keep, does the U.S. abandon the clock changing? And if so, what does the science say about whether the country adopts permanent daylight saving time or year-round standard time? You're listening to Shortwave. The Daily Science podcast from NPR. It's only two weeks ago that we set our clocks forward an hour. And I had to like remember which buttons to push on the microwave to make it happen. But, you know, unless you went to bed an hour early, most of us lost an hour of sleep. It's kind of tedious. But having our bodies adjusted by now? You would think that it wouldn't be a big deal to adjust to a one hour change in time. In this instance, losing an hour, basically having a 23-hour day once a year. But our body's going to tell a different

story. I mean, what's surprising is that the springtime clock change is actually, linked to an increased risk of heart attacks and other cardiac events. And I talked to a cardiologist. His name is Jay Chudau at Montefiore Health, who has actually documented this phenomenon. He compared hospital admissions for a type of heart arrhythmia or irregular heartbeat called atrial fibrillation in the days after the spring time change compared to the rest of the year. We found that there were more hospitalizations for atrial of relation after the spring time change, I was very surprised because it's just one hour change. Why should it cause this large effect?

He says people who ended up in the hospital with AFIB, as it's referred to, had other risk factors too. These weren't young, healthy people. So the time change wasn't the sole cause of their event, but likely the factor that put them over the edge. So why does this happen? Do scientists know? Exactly why isn't nailed down yet. But What has become clear is that our bodies are super sensitive to time, as we just heard above. A few years back, three scientists actually won a Nobel Prize for their work that helped made that discovery that we have clocks running in every organ and every cell of our body. And that we're just orchestral beings, literally timekeeping machines.

That's right. It's one way to look at it. I mean, and it really, the analogy really does hold up. I mean, the first rays of light each morning helps to reset our. clocks each day. And with that abrupt change, that 23-hour day when we spring forward, it can disrupt our internal clocks in ways that can be harmful. In addition, think about this, Emily, when much of the nation is tired and groggy on a single day from collectively losing an hour of sleep, it can lead to a lot of distracted drivers on the road. Traffic accidents after the time change, there's definitely a signal that there's more of those after we change the clocks, just like there are more workplace accidents and such.

And if I can make my own admission, I was involved in an incident on the Wednesday after the time change last week. He collided with another car. I don't have all the details, but it was not his fault. And Emily, this may seem like a coincidence, but it turns out I was also involved in a traffic incident, the day of the spring forward change. Oh, no. Are you okay? I am completely fine.

What happened is I actually backed into my neighbor's Tesla. He was not in his usual parking space. I was in a hurry, running late, and boom, it was just easy to do. I didn't look in the rearview mirror. Thousands of dollars later, questioning why this happened. I decided to reach out to the circadian medicine clinic at Northwestern. I spoke to Dr. Sabra Abbott. She's a neurologist by training, and her research focuses on understanding the impacts of timing on our health.

Can you claim daylight savings time is to blame? Probably. I don't know if that would hold in court, but you probably were sleep deprived. You were probably a little misaligned. And I think that probably played a role in that. Now, thankfully, no one was hurt in my fender bender, which is the most important thing. But one study from 2020 found a 6% rise in fatal car crashes after the spring time change. Wow. You know, the data is a little bit mixed on this. Some studies point to higher risks of accidents. in the morning during daylight savings months due to the darkness in the morning. It can kind of go both ways. But Abbott says what is very clear is that there are negative health effects linked to shifting the clocks.

This is fascinating to me. And, you know, it's tough to determine causality here, like she's saying. But part of the scientific process is stepping back from individual experiences and looking at broad trends. And if you're saying that health and safety kind of trend in a bad direction around this time, of year because of the clock change. What is the conversation like about doing away with it entirely and just keeping to one time in the U.S.? I think there's a lot of support for that. There's support among politicians, among some scientists, support among people who are just annoyed by the time change. But I think the big question becomes which time should become

permanent? Should we adopt standard time year round with more sunlight in the morning or permanently adopt a daylight saving time with more sunlight in the early evening, as the Senate has voted to do. Well, if the early race of the sun reset to human clock, wouldn't daylight saving time kind of misalign with our natural rhythms? Well, that's exactly the concern. And Dr. Abbott says a lot of sleep scientists think that the Senate got it wrong. One of the consequences of permanent daylight savings time is actually that you end up finding it harder to fall asleep at next. because you're getting that light later in night when it actually pushes time later and you're getting less of that light in the morning, which makes it harder to wake up in the morning. In fact, the American Academy of Sleep Medicine has a position paper on this in favor of moving to permanent standard time. So more light in the morning.

Yeah, you're trying to like align what's happening in the environment with the clock in a person's body. So if sleep doctors mostly prefer permanent standard time, why did the Senate choose? the other direction. Why did they go for like a permanent daylight saving time? Yeah, I think to answer that, you have to go way back when daylight saving time was first introduced as a concept about 100 years ago. The idea back then is that it would save energy. If people need less power to heat their homes in the evening, there'd be some energy efficiency. But it's not clear that this energy efficiency has really ever panned out. The argument today that's more relevant, I think, is that more sunlight in the afternoon makes it easier for people to go out and do things after work

and spend more money doing it. I spoke to Lyle Beckwith. He's with the National Association of Convenience Stores. And that group actually lobbied way back in the 1980s to extend daylight saving time for a longer stretch of the year for this very reason. When people come home from work and there's more daylight, they tend to be more active. They go to sporting events, they play softball, they golf, they barbecue, and that translates into a increase in sales of people coming in to buy more water, more Gatorade, more beer, more charcoal, more everything. They don't have specific numbers on this, but he says stores tell him that they see a 15 to 20 percent boost in sales at this time of year. Yeah, I'm guilty of this. I'd be in that data. But, you know, this is just like human health colliding with kind of economic health.

It's a story that is classic. And you said, though, it's unlikely such a change will become federal law this year, even if the conversation has been stewing for a long time. You know, I think Congress may end up giving up on the measure this year because, let's just face it, there are lots of high priority issues right now. There's Ukraine and inflation. I mean, the House of Representatives does not have a plan at the moment to vote on it, though it is worth noting that it passed the Senate by unanimous consent, meaning no one objected to it. There was no actual roll call vote. So it does have some momentum. And if Congress did act, many retailers say they would rather see permanent daylight saving time. So the question is like where does that leave all of us, right? As a human being, I mean, where I've kind of landed is, I guess. it that, you know, standard time with more light in the morning is probably what our natural rhythms are craving. However, you know, as a person who works during the day, I also like the idea of being able to, like, play tennis or meet people in the afternoon after work,

and it's still light. So in a way, we're kind of living this compromise, you know? Yeah. So I guess I'll see you at the 7-Eleven picking up charcoal for the time being. All right. You're inviting me over for a barbecue. Is that right? Yeah. Do I have that right? Thanks, Allison. Thank you. This episode was produced by Thomas Liu, edited by Jane Greenhalsh, and Jazele Grayson, and fact-checked by Catherine Seifer. Giselle Grayson is our senior supervising editor. Andrea Kisick is the head of the science desk.

Edith Schapen is the executive editor and vice president of news. And Nancy Barnes is our senior vice president of news. I'm Emily Kwong. I'm Alison Aubrey. Thank you for listening to Shortwave, the Daily Science Podcast from NPR.