March 12 might be the last time you set your clocks one hour ahead—or “spring forward”—for daylight saving time (DST). Last year, the U.S. Senate passed a bill called the Sunshine Protection Act to stop the biannual clock changes. As of press time, it has yet to become law.
The U.S. first adopted DST in 1918 because the world was at war. By changing clocks, workers had more hours of daylight to make wartime supplies. The U.S. dropped DST after winning the war, but reinstated it for World War II—and has kept it since.
Why drop DST? One of the most important things our biological clocks do is respond to the natural rhythms of the sun, moon, and tides, says Till Roenneberg. He’s a professor in Germany who studies biological clocks. So any change that disrupts the body’s internal 24-hour cycle is biologically dangerous.
With DST changes, our body clocks are pulled out of alignment. “Humans think that they can just ignore nature,” says Roenneberg. “But it always has consequences.” One of the biggest is social jetlag, or when your internal clock feels out of sync with your daily activities. It’s the heavy slowness you feel after losing an hour of sleep every March.
If the Sunshine Protection Act becomes law, the U.S. will switch to permanent DST. Though this won’t be the first time. We already tried it in 1974, and people hated it so much that it didn’t even last a year! Do you think we should change it?