Where did Daylight Saving Time come from? KSAT Explains

One hour makes a big difference. Medical pros say our bodies never really catch up.

We “spring forward” in March and “fall back” in November.

That’s the beginning and end of Daylight Saving Time.

The one-hour time change is a challenge to the body’s naturally occurring internal clock, or circadian rhythm.

“This circadian rhythm is tightly bound with the exposure to light. So whenever we expose somebody to extraordinary amount of light, or they are exposed to prolonged period of darkness, that may throw their circadian rhythm off,” said Dr. Suhaib Haq, Senior Medical Director with University Health.

During Daylight Saving Time, we get more light in the evening and less light in the morning.

“That causes the body to be exposed to less amount of bright light in the morning that it needs to keep the circadian rhythm in check,” Haq said.

Where it came from

The Germans came up with the idea of Daylight Saving Time in 1916 during World War I. The intent was to save energy on coal production.

The U.S. adopted the time change in 1918, but ended the practice after the war.

It was reinstated during World War II but finally became a non-war time, annual system in 1966.

Today, the intent of Daylight Saving Time is negligible.

“The evidence is that savings is really small from daylight saving,” said David Macpherson, a Trinity University n economics professor. “You can get some studies showing one way or the other, but they’re so close to zero. What’s the point?”

There are, however, studies that show heart attacks and strokes increase after losing an hour of sleep, as well as car accidents.

Haq said many people think their bodies “catch up” to adjust to the time change, but they don’t.

“That’s why American Academy of Sleep Medicine recommends to do away with the time change,” he said.

Lawmakers at both the state and federal level have tried unsuccessfully to do that.

High school students are typically the most affected by the time change because the circadian rhythm of teenagers is delayed.

“It means they go to bed late and they wake up late,” Haq said. “That affects them because they don’t get enough light exposure at the right time, and they may tend to be more sleepy.”

Get back on track

To get your rhythm back in check after Daylight Saving Time begins, Haq recommends getting more sunlight in the morning hours.

Also, eat dinner a little bit earlier. That gives your body a cue that bedtime isn’t far away. If you eat earlier, you might might be ready for sleep earlier.

Before the time change occurs, try pushing your bedtime earlier by 15 minutes a day for the week prior.

The reverse is suggested when its time to “fall back”: try pushing your bedtime 15 minutes later for a week before the swtich.

About the Authors

Myra Arthur is passionate about San Antonio and sharing its stories. She graduated high school in the Alamo City and always wanted to anchor and report in her hometown. Myra anchors KSAT News at 6:00 p.m. and hosts and reports for the streaming show, KSAT Explains. She joined KSAT in 2012 after anchoring and reporting in Waco and Corpus Christi.

Recommended Videos