“Daily Saving Time is a misalignment of our biological rhythm or circadian rhythm
for 8 months of the year.”
– Beth Malow, Professor of Pediatrics and Neurology, Vanderbilt University
It’s very hard NOT to write about COVID today. There are so many medical fun facts swirling around out there. Can we get COVID from our pets, our school children, or during sex? The answer is “no” x 3. In fact in one study most of the school-aged children who got the virus did so from their parent(s), not visa versa. Is alcohol consumption up during the epidemic? Yes, but only moderately. One study showed that people were drinking 6 1/2 days a month rather than 5 days a month compared to past years. . . . However, I am more than a little saturated by the flood of news about COVID and its vaccines. Maybe we’re drinking more because 5 PM arrives an hour earlier . . . and that’s what I’m writing about today, Daylight Saving Time.
We sprang ahead one hour on November 1 (the first Sunday in November) in compliance with a 1966 federal law, the Uniform Time Act. It did not mandate instituting DST, but it did mandate that if a state switched times it had to do so on the first Sunday in November and the second Sunday in March. Congress passed this law to remedy the existing chaos of states switching time on different dates.
The medical effects of DST are mixed. Depression increases in the first few weeks after the switch to ST in the fall. Heart attacks increase 24% on the Monday and for the two weeks after the switch to DST in the spring. Teenagers sleep about 2 1/2 hours less per night after the switch to DST. There is a brief spike in car accidents right after the switch to DST, presumably due to “decreased alertness in the early morning”.
Why do we switch? The founder of DST is either Benjamin Franklin in 1748 or George Hudson in 1895. Ben’s rationale was that the extra hour of light at the end of the day “would let you work rather than use energy for lights.” George Hudson was an entomologist in New Zealand, and he cherished an extra hour of daylight to collect more insects (true). It is apparently a myth that DST was started by the farmers who get up early anyway and want to spend another hour in the fields.
Ben’s argument for saving energy remains controversial. We instituted DST during both World Wars (presumably to save energy, and because Germany had already done so), but went back to Standard Time in between. In fact, DST was called “war time” then. We again instituted year-round nationwide DST during the oil crisis in 1973-1975. A National Bureau of Standards 1975 study found no differences in health status or energy usage between DST and ST. A 2007 Report to Congress documented that electricity usage decreased by only 0.34% over the first four weeks of DST. Critics of the energy saving argument make a point that DST is “Daylight Saving Time”; there is no “s” on the end of “Saving”, i.e. there is no “savings” involved.
The most consistent argument for DST seems to be that “people just love that extra daylight in the evening.” (I’ll vote for that!). So why not have DST all year long? Eleven states do have year-round DST by their choice. None of the New England states do, but there is a proposal that four of them switch from Eastern Standard Time to Atlantic Standard Time which would move their clocks ahead one hour for the whole year. A Massachusetts Special Commission endorsed that idea in November 2017 (note the month). Russia tried full year DST in 2011, but when sunrise in Moscow kept arriving at 10 AM Putin nixed it in 2014. China, (oh oh) has no DST. Europe has DST like us and calls it “summer time”.
Academic critics of DST emphasize that it is not only the stress of the time switch (“Its the transition, stupid”), but that DST is “misaligned with our natural circadian rhythms.” Pets do react to the change of time, but there is no effect on the timing of deliveries of human babies. We do adjust to the time change. Studies of jet lag have shown that it takes a 1 day for each hour of time change. In 2020 The American Academy of Sleep Disorders (don’t you dare fall asleep during one of THEIR lectures) endorsed year round Standard Time as “the best alignment with our own body rhythms”. The Department of Transportation announced in June 2020 that it was doing “a literature search of DST and Standard Time issues”, but as of September 2020 there has been no report published.
Some researchers have suggested that this year’s time switch will cause LESS stress because the pandemic has “freed up our time schedules”. We don’t have to get up to go to work or school; each day seems like the previous one; we set our own daily schedules. OMG, there I go, back to writing about COVID again! Of course, “we ain’t seen nuttin’ yet” in terms of COVID medical fun facts. Brace yourself for all the future studies of COVID and alcohol consumption, use of social media, gasoline usage, depression, divorce rates, doctor visits, telemedicine use, causes of death, etc. . . . I can wait. We are all used to waiting right now, aren’t we?.
HUB's LIST of medical fun facts 