This week, we set our clocks forward one hour, sacrificing an hour of sleep in exchange for longer daylight in the evening. The concept of shifting an hour of sunlight from morning to evening is often credited to Benjamin Franklin, who, after noticing he was wasting daylight by sleeping in, jokingly suggested in a satirical letter that the French fire cannons at sunrise to wake people and reduce candle consumption. While we no longer rely on cannons, many of us still struggle with the adjustment, waking instead to the sound of our alarm clocks.
The Industrial Revolution helped turn Franklin’s idea into government policy. Throughout much of the 1800s, time was set according to the sun, with each town and city maintaining its own version of “sun time.” As a result, noon in New York might be 12:30 p.m. in North Carolina and 12:15 p.m. in Massachusetts. These discrepancies created major challenges for railway companies trying to keep schedules consistent. To resolve the confusion, British railroads adopted standardized times in the 1840s, and American rail companies soon followed suit to prevent federal intervention.
On Nov. 18, 1883, North American railroads implemented Standard Railway Time (SRT), introducing the time zones we recognize today: Eastern, Central, Mountain and Pacific. Initially designed for train schedules, these standardized time zones were widely adopted across the country. Federal regulation of civil time followed on March 19, 1918, when the Standard Time Act was signed into law, officially establishing daylight saving time.
Daylight saving time was initially introduced to reduce energy costs, though this has not always been the case. In response to a fuel crisis, President Richard Nixon signed the Emergency Daylight Saving Time Energy Conservation Act in 1974. Originally intended as a two-year experiment, it was abandoned after only eight months due to widespread public dissatisfaction.
While many business owners support daylight saving time for its economic benefits, there is ongoing debate about its necessity. Some U.S. states, including California, Florida and Ohio, as well as the European Union, have considered abolishing the time change. In March 2022, the Senate unanimously passed a bill to make daylight saving time permanent, but the legislation stalled in the House. Former President Donald Trump has expressed support for ending the twice-yearly time change.
Other regions have already abandoned daylight saving time. In October 2022, Mexico eliminated it for most of the country, except for some states near the U.S. border. China, India and Russia also do not observe daylight saving time. In the U.S., Hawaii and most of Arizona opt out, though the Navajo Nation in northeastern Arizona follows it. Several U.S. territories, including Puerto Rico, American Samoa, Guam and the U.S. Virgin Islands, also forgo the practice.
Research suggests that daylight saving time negatively impacts health, increasing risks of heart attacks, strokes and sleep disorders. In 2023, the American Academy of Sleep Medicine issued a statement advocating for its elimination. “By causing the human body clock to be misaligned with the natural environment, daylight saving time increases risks to our physical health, mental well-being and public safety,” the AASM stated.