Editorial
What time is it really? Maria J. Sunseri, MD FAASM
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he American Academy of Sleep Medicine (AASM) did initially support the U.S. Senate for passing the “Sunshine Protection Act” which, by 2023, will eliminate the biannual time changes of “falling back” in November and “springing forward” in March. However, the chosen time committed to by our government of permanent Daylight-Saving Time (DST) goes against all the scientific evidence presented and a prior “pilot trial” of continual DST in the U.S. during the 1973 OPEC oil embargo. Therefore, the AASM has come out against the Sunshine Act for this reason. References for this discussion are taken from the Position Statement on DST by the AASM from 2020 and a discussion group by Erin Evans PhD at the APSS annual meeting. It appears that our representatives state that they are told that most of their constituents want permanent DST. This is the initial reaction of many at first, including myself, until I reviewed the evidence of what we have learned about our light/dark cycle and our circadian rhythm over the years. Most of us feel better in the Spring when the days get longer, warmer and vegetation blooms. It is our job as scientists and medical doctors to not just go by what we feel but to look at the evidence and then educate and inform our patients 8
why DST is not the best option, and the better choice is permanent Standard Time (ST). In the world of Sleep Medicine, it has become apparent over the last 30 years that our circadian rhythm plays a supreme role in our overall health. It not only controls when we eat and sleep but the health of organs at the cellular level, our aging, our mood and attention. Our circadian rhythm is entrained by the light/dark cycle. Standard Time is when sun time and clock time are aligned. Therefore, our circadian rhythm is entrained by the “correct” light/dark signals and has the best chance to be “in alignment”. DST changes the clock time but not the sun time, so it is like living in the wrong time zone. Your circadian rhythm is “out of alignment.” So why is this important? The evidence shows that with this switch from ST to DST there is an increase in cardiovascular morbidity, increase in strokes, mood disturbances, and motor vehicle accidents—primarily in the morning. There is more sleep deprivation from this misalignment due to increased light in the evenings causing people not to fall asleep as early, but they still have to get up at the same time. This is a situation of sleep phase delay, sometimes termed “social jet lag” that can become chronic and cause chronic
sleep deprivation. Sleep deprivation causes many health consequences, not the least of which is a 5% increased risk of all mortality. It can cause cellular derangements, altered gene expression, altered epigenetic and transcriptional clock genes, increased inflammatory markers, and increased heart rate and blood pressure due to lower vagal tone. “Social Jet lag” has been associated with an increased risk of obesity, metabolic syndrome, cardiovascular disease, and depression. This situation is exacerbated the further west you live in each time zone as the sun sets latest the further west you live. There is an increased risk of cancer for each 5 degrees (20 minute) off the meridian of each time zone. This move to permanent DST would also negate the positive effect that we have worked so hard for to get the schools to move their start times later and the benefit that that was meant to achieve. In 1973, during the OPEC oil embargo, temporary year-round DST was instituted in the U.S. There was an increase of fatalities among school age children in the morning between January and April. This could have been due to the increased darkness in the morning, but further analysis was not done. The energy data for why we do this switch to DST was evaluated in www.acms.org