The daylight saving debate

    Spring forward and fall back, or reassess?

    The debate surrounding daylight saving time is more heated than ever before. There are three options available in the U.S., and other countries also have ongoing debates:

    1. Continue switching times twice a year
    2. Make it daylight saving time (DST) all year round
    3. Make it standard time (ST) all year round

    Is DST a boon or a net negative? The first option is quite unpopular. A majority of the American public favors keeping DST all year, along with many legislators. Sleep scientists and circadian biologists tend to favor keeping ST all year round.

    Hawaii is close to the equator, so they stick to ST, as does Arizona, but for extreme-heat related issues. Every other state switches twice a year, giving you double the opportunity to forget to change one of your clocks.

    There are many issues at play here: energy consumption, public safety, and so on. When so many complex issues collide, countries usually conduct detailed analyses and consult leading experts in each of the involved fields.


    You may be aware of something called “politics”. No matter your expertise on relevant issues, your opinion isn’t as important as that of politicians and lobbyists. That may sound bitter, but politics comes up way too often when discussing science-related issues.

    After the spring time change this March, a former Examine researcher asked if I might want to help educate people about relevant daylight saving issues (Hi Kristen!).

    She happens to have completed a fellowship in sleep and circadian biology.

    We usually rely on our own independent analyses and don’t share outside links, but in this case, the topic is best addressed by outside experts. Here’s a succinct explanation of the science from a piece by the American Academy of Sleep Medicine (AASM):

    “The one-hour time shift during daylight saving time results in less exposure to light in the morning and greater exposure to evening light relative to typical sleep and work schedules. As a result, we tend to go to bed and fall asleep later, resulting in chronic sleep loss. Daylight saving time causes ongoing misalignment between our sleep/wake rhythm and the light/dark cycle, also called “social jet lag.”

    “The daylight saving time changes can be especially problematic for any populations that already experience chronic insufficient sleep or other sleep difficulties.”

    Of course, there are other issues at play as well, outside of circadian biology. But anyone with sleep issues knows that sleep is often the single most important factor influencing health and happiness. If you feel strongly about the issue, the AASM provides a link for Americans to easily contact their representatives.


    Kamal Patel
    Co-founder, Examine