Escape the Burden of Switching to Daylight Time

Our inner clock doesn’t know that the government has rescheduled our lives.

Michael Terman, PhD

Just when you are used to Standard Time, the annual return to Daylight Time arrives. Here, Michael Terman, PhD, warns us of what to expect the next time we need to adjust our clocks.

It happens every year around this period. Those clock faces with arrows on the TV news. The abrupt time change on the cable box and the cellphone. The more gradual changes as you try to remember to reset all the clock-like devices around the house. The forgotten alarm that goes off an hour earlier than you expected. And which button do you push to reset the dashboard clock in the car?

The annual springtime return to Daylight Time—which happens this year at 1 a.m. on Sunday, March 9—may seem to be just one more of those minor inconveniences of modern life.

But is it so minor? According to a recent study published in the New England Journal of Medicine, during the week after the shift into Daylight Time, the rate of hospital admissions for heart attack rose by as much as 10 percent. Another recent study compared high school students in parts of Indiana that use Daylight Time with those in other parts of the state that stay on Standard Time year-round. On average, those who were subjected to Daylight Time had SAT scores more than 16 points lower than those in areas that didn’t shift the clock!

Why? The simplest explanation is that the shift confuses the circadian clock in the brain. This inner clock relies on timed exposure to light, especially natural light, to keep itself in sync with the daily cycle of 24 hours. But the sun doesn’t “spring ahead” on March 9, and neither does your inner clock.

Let’s say your daily rhythm is going to sleep at 11 p.m. and waking up at 7 a.m.. If you live somewhere near the middle of the continental US, that means that during the first week of March, while you’re still on Standard Time, you wake up to find the sun is already up. So far, so good. But come Monday, March 10, when you get up as usual at 7 a.m., it’ll still be dark out for another half an hour or more. You’ve lost an hour of sleep, and your daily rhythm of energy and mood lags an hour behind where it usually is.

To adjust to this, you have to It happens every year around this period. Those clock faces with arrows on the TV news. The abrupt time change on the cable box and the cellphone. The more gradual changes as you try to remember to reset all the clock-like devices around the house. The forgotten alarm that goes off an hour earlier than you expected. And which button do you push to reset the dashboard clock in the car?

The annual springtime return to Daylight Time—which happens this year at 1 a.m. on Sunday, March 9—may seem to be just one more of those minor inconveniences of modern life.

The loss of an hour in March is hard on a lot of people. It is particularly hard on those who are battling winter depression. After March 9, according to the clock, sunrise will come as late as it did at the end of December, during the darkest days of the year. Sure, we also get an hour added on at the end of the day, but that’s no help. It is early morning light that our inner clocks rely on to keep in sync with the external world.

Can we do anything to make this transition easier? Well, yes, we can—but it means thinking ahead. The key is to be proactive. Make the adjustment ahead of time. Help the inner clock accommodate to the change gradually, before it happens. In a nutshell, that means waking up and turning up the lights 10 minutes earlier each day for the six days prior to the time change.

That means making a correction of a full hour, plus the daily correction of 20 minutes or so. Not so easy, especially when the morning light that helps you do it doesn’t show up until an hour later. Most of us need a week or more to adjust, and some researchers suggest that our clocks never fully adjust to Daylight Time.

During the week before Daylight Saving Time in early March, and Standard Time, in early November, follow us on Twitter (or @mychronotherapy) to receive daily reminders and news about how to best adjust to losing, or gaining an hour.

This Is Why Street Lights Can Be the Worst Idea in the World

Now an estimated 300,000 million street lights brighten the world.

Street lights create unintended consequences. For example, during the French revolution, they were convenient spots to hang aristocrats. A mob’s cry, “À la lanterne!” was fatal.

Today, street lights have different unintended consequences. They are less dramatic, but more far-reaching, than the murder of aristocrats in Paris.

Mixing Day and Night

Many of us get artificial light at night from street lights. This light suppresses the secretion of the sleep hormone, melatonin.

Newton (1643-1727) shone white light through a prism, and found a spectrum.

Further, this light, while white, includes the blue part of the spectrum. This part of the spectrum energizes us.

 Thus, exposure to light at night makes it is hard to sleep, and weakens our natural circadian rhythms.

The paltry amount of sun most of us get during the day adds to the confusion of our inner clock.  We usually feel we are getting enough illumination when all the lights are on inside our homes and office buildings during the day. However, even then we average much less exposure to light than we would if we were outside on a cloudy day.

Getting the wrong amount of light at the wrong time puts us at risk for insomnia, problems with alertness during the day, and so on. So while street lights serve many useful functions, they also confuse the timing and coordination of many functions, from sleep to digestion.

Shirking the Night Shift

Dr. Knop and her colleagues found that cabbage thistles in lit (vs dark) fields had 13% fewer fruits.

Too much light at night is a problem for other living things as well, as Eva Knop, and her colleagues from the Institute of Ecology and Evolution at the University of Bern, demonstrated in August 2017. They added the equivalent of street lights to five fields, and kept five fields naturally dark. They then compared the nocturnal pollination in the two groups of fields.

When the moths, and other insects, were in fields with lights at night, these nocturnal pollinators were far more likely to ignore their pollinating responsibilities. Specifically, nocturnal pollinators were about two thirds less likely to visit the flowers in the meadows with artificial light. This decreased the fruit set, and hence the reproduction, of plants.

“The pollination during the day obviously cannot compensate for the losses in the night,” notes Dr. Eva Knop.

These findings are serious because:

  • light emissions are increasing as residential areas increase worldwide
  • daytime pollinators, such as bees, are decreasing worldwide
  • it appears that nocturnal pollinators indirectly aid daytime pollinators, so a loss of nocturnal pollinators would have a ripple effect.

The Bottom Line

While artificial light can be a blessing, we are just beginning to see, and understand, a new kind of unintended consequences. Unfortunately, these consequences may snowball as we become increasingly urban, while still living in an interdependent web of existence with insects, and plants.

Related Reading

The Danger of Mixing Day and Night

When the Light You See Is Not the Light You Want

Interminable Terminal Insomnia

When a clinician’s bag of tricks is no match for her early morning waking

One of my least favorite symptoms of seasonal affective disorder (SAD)―not saying I enjoy the low mood, decreased energy, and impaired concentration―is terminal insomnia.

Terminal insomnia is also known as “early morning waking.” It can take place anytime between 2 and 4 a.m., and it’s usually difficult to fall back asleep. It’s a well-known symptom of non-seasonal depression, but not so well known for SAD. If you’ve read any magazine story about SAD, you’ve no doubt gotten the impression that oversleeping is the problem―but certainly not for me.  Why should I be so different? Continue reading

Complicated Grief and the Inner Clock

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Abigail Strubel, MA, LCSW, CASAC,

When is poor sleep a sign of a broken heart?

One of my most poignant patient interactions in the methadone program where I used to work was with a 73-year old woman I’ll call Maria. She suffered from numerous health problems in addition to her heroin addiction, including obesity, diabetes, a bout with breast cancer in her 40s, high blood pressure and elevated cholesterol levels.

But when I met with Maria to discuss enrolling in a geriatric case management program to help her better handle her health issues, all she could talk about was her late daughter, Isabel. How beautiful Isabel had been, how young when she passed away, what a perfect companion she was, and how lost and lonely Maria felt without her.

“I don’t care if the cancer comes back,” she told me. “Without Isabel, my life is pointless. I just want her with me again. I miss her so much. It feels like she died just yesterday.”

In fact, Isabel had died more than 15 years prior to our conversation. Maria’s feelings were typical of someone experiencing complicated grief, which is defined as negative feelings related to a loss that persist for at least six months, and impair a person’s ability to cope with and enjoy life. One prominent symptom of complicated grief is sleep problems. Continue reading

More Than A Shift: The Difficulty of Moving on From Nighttime Work

It’s well known that nightshift work can be harmful to your health. By disrupting the body’s natural circadian rhythm, nightshift work causes unnatural sleep schedules that can have serious effects on physical and mental health as well as on relationships. Among other things, sleep rhythm disruption can cause irritability, decreased energy, depression, and even, according to the World Health Organization, an increase in the growth of cancer cells, giving new meaning to the term ‘graveyard shift.’

There is another danger of nightshift work that hasn’t received so much attention, however. While many are warned of the dangers of such labor, few understand how difficult it can be to break the routine that imprisons so many night-shift employees. Indeed, once informed of the hazards of nighttime work, one may ask them, “Why not look for another job?” The answer to such a question lies, unfortunately, in the addiction-like, habit-forming nature of the work.

Take a look at Mitu, a 43-year-old food cart worker in New York City. Hailing from Bangladesh, Mitu arrived in the United States in 2008 and eventually landed steady work at a Halal cart, operating it from 8 PM to 8 AM, after which he begins an hour-long commute home from Manhattan.

“I am often very tired,” Mitu says. “I can only sleep between maybe 11 AM and 4 or 5 PM, and never all the way through.” Along with affecting his physical life, nightshift work strains Mitu’s relationships as well; many days he is unable to see his wife at all due to their mismatched schedules. Because she works during the morning and evening, she often leaves for her job before Mitu is up and returns home hours after he has left.

Despite his chronic fatigue and taxed relationship, though, Mitu cannot escape from the habits he’s mired himself in. After six years of working night-shift jobs and perpetuating an errant sleep schedule, he actually opposes a move towards working different hours. When asked what shift he would choose to work if he became a taxi driver (such, Mitu revealed, is his goal), he said, “Nighttime – definitely nighttime. Ever since coming to the United States, every job I [have] worked is a nighttime job. It was because I came straight from Bangladesh, and day there is night here. So from the start it was easier to work at night, and today I still do.”

In the city that never sleeps, there are countless late-night workers. Many, like Mitu, have altered their lives to fit work schedules, enduring various hardships to do so. As is the case with many who have destructive habits, the negative effects of working the nightshift haven’t provoked Mitu to seek a way out of it. Perhaps one ought to consider, then, before agreeing to any consistent late-night work, not only the problems that come from it, but also the seeming grip the nightshift has on those who work it.