Story at a glance

  • Daylight saving time was created to conserve energy, but research shows it has little impact on our modern consumption of electricity.
  • But losing or gaining an hour of sleep has profound — and even deadly — effects on human health.
  • Some scientists are making the case for abolishing daylight saving time, for our own good.

The idea of falling back and springing forward goes all the way back to Benjamin Franklin, who conceived of it as a way to conserve energy by making better use of daylight. But daylight saving time (DST) has serious effects on our health, and the evidence that it saves energy turns out to be slim.

Losing an hour of daylight in the fall has been linked to an increase in depression, and losing an hour of sleep when daylight saving time resumes in spring coincides with an increase in heart attacks, car accidents and workplace injuries, the Associated Press reports. 

"That's how fragile and susceptible your body is to even just one hour of lost sleep," sleep expert Matthew Walker told Business Insider. 

Apart from its potential impacts on our mood, gaining an hour of sleep in the fall provides a health boost. The same study that found heart attacks increase 24 percent the day after the start of DST in spring also showed a 21 percent decrease the day after we fall back. 

Messing with the clocks on our walls also scrambles the body’s internal clock — what scientists call our circadian rhythm — that takes its cues from sunlight and darkness. Our circadian rhythm regulates the release of hormones that control bodily functions such as when we get sleepy, blood pressure and how our body processes food. As a result, when our body’s clock is out of whack it can contribute to obesity, depression, diabetes and heart problems. 

In the U.S., states can opt to remain on standard time year-round, but only Hawaii and parts of Arizona have ditched DST. Some scientists advocate that the roughly 40 percent of countries around the world observing DST abolish it for the good of their citizens’ health. 

Published on Nov 08, 2019