Why Staying on Standard Time Can Yield Incredible Benefits: Guest Op-ed by Dr. Nate Watson
Dr. Nate Watson is chair of the SleepScore Labs Scientific Advisory board, serves as director of the Harborview Medical Center Sleep Clinic and co-director of the University of Washington Medicine Sleep Center, and is the former president of the American Academy of Sleep Medicine and American Board of Sleep Medicine.
H.G. Wells wrote The Time Machine in 1865, a story about a fantastical device that could move a human through time unscathed, to remedy mistakes of the past, or view the opportunities of the future. Unfortunately, the time travel you do during Daylight Saving Time (DST) clock adjustments does not use this machine, but rather, is a social construct imposed on our body clock moving it away from its natural master – the sun – to the detriment of human health and performance.
Understanding the clocks that influence our health
To understand this better we need to talk about clocks, and how the interaction of three separate clocks influences human physiology and health. First, the body clock, the internal clock that organizes our biology and creates daily rhythms – such as when we eat and sleep, when we perform optimally both mentally and physically, and how the rhythms of our body organs function together in harmony. Second, you have the sun clock, whose rhythmic patterns of light and darkness entrain our body clock to the 24-hour day. Consider when early archaic humans walked the earth ~700,000 years ago, widespread control fire occurred ~125,000 years ago, and the light bulb was invented by Thomas Edison 140 years ago. So for the better part of 600,000 years, the only light influencing our body clock came from the sun. The sun clock is truly our body clock master. Third, you have the social clock, a human construct originally created by the Railroad industry 138 years ago to keep trains running on a predictable schedule. At the time they created 24 one-hour time zones that defined work, school, and social schedules.
We live according to the same social clock within a time zone, but as long as we can still see the natural light of day, our body clocks still follow the sun clock defined by the sun’s east/west path. Thus the body clock of a person living on the eastern edge of a time zone is earlier and more in tune with the sun clock than a person on the western edge of a time zone. For instance, when two people wake up at 7 am for work in a given time zone, the body clock of the person on the eastern edge may be set to 7 am, but that of the person on the western edge may be set to 6 am creating desynchrony between the body clock and the sun clock. Research shows the further west we live in a time zone the more health problems we have and the shorter we live. So DST doesn’t add a single second of additional daylight to a 24-hour day, but moving clocks forward, as we do on the second Sunday in March, does essentially move you westward within your time zone to the detriment of your health and well-being. This is akin to dosing the entire population with an hour of permanent jetlag.
What is DST?
So, what is DST and who came up with it? Ben Franklin, who quipped, “early to bed and early to rise makes a man healthy, wealthy and wise,” wrote a letter of satire in 1784 to the “Journal de Paris” chiding lazy Parisians by pointing out that they could save money on candle wax if they woke earlier to take advantage of morning sunlight. So, the original idea was Franklin’s, but warfare made it necessary and greed kept it going. On April 30th, 1916 Germany together with its allies implemented DST to alleviate hardships due to coal shortages and air raid blackouts. The UK and the USA soon followed suit to support their war machines.
Following the war, the US congress repealed DST twice, but President Woodrow Wilson vetoed both measures because, as an avid golfer, he was bothered that his golf rounds were often cut short by darkness. The second veto was overridden. The US went into permanent DST during WW II from 1942-1945 and in 1973 during the OPEC-backed oil embargo, both times to save energy. Through the years, there was so much widespread variability in the implementation and timing of DST, you could take a 45-minute bus ride from West Virginia to Ohio and the time would change seven times. The Uniform Time Act was implemented by the federal government in 1966 standardizing the dates of DST. This act does not require states to recognize DST, and Hawaii and Arizona currently stay on ST year-round. Because it standardizes the timing of DST, states cannot opt to go onto permanent DST unless this federal law is changed. DST was extended in 1987 and 2007. Both times funding in support of these extensions came largely from the National Association of Convenience Stores and the Sporting Goods Manufacturing Association. Two Idaho senators voted for extending DST in 1987 on the premise that more French Fries are sold on DST.
Daylight Saving Time proponents
DST proponents tout energy savings, increased outdoor leisure activity, reduced crime, and increased business opportunity as benefits. Opponents point out energy is not saved. Extra heating fuel on colder, darker mornings, increased air conditioning use on longer hotter summer days, along with increased fuel use from driving to shopping outlets and outdoor activities cancel out any electricity savings. The negative health impact of DST is astonishing. DST is associated with a 10% increase in heart attacks, an 8% increase in stroke risk, increases in depression and suicidality, and increases in the number and severity of workplace injuries and motor vehicle accidents immediately following the time change.
SleepScore Labs’ research shows that following DST in the spring, people sleep 40 minutes less per night. This sleep deprivation persists for weeks following the time change. Sleep deprivation is associated with obesity, cardiovascular disease, depression, diabetes, and increased motor vehicle accidents. Beyond negative health impacts, DST creates the hassle of changing clocks twice a year with disruption to meetings, travel, broadcasts, billing systems, records management, and computing-related errors in healthcare and business. Despite all these negative effects, the change back to ST in the fall has negligible effects either way with little evidence we use the extra time to increase sleep. All told, the opportunity cost of DST is estimated at $1.7 billion dollars annually. So DST essentially sacrifices our body clock health for somebody else’s profit. Have you agreed to this trade-off? Are you ok with it?
The benefits of Standard Time
Contrast this with the beauty of ST. Nearly 70% of countries in the world stay on ST year-round so we would be aligned with the majority of the world. Staying on standard time better synchronizes the body clock with the sun clock and people will sleep earlier relative to their work and school start times. Sleep deprivation is an epidemic among the youth in this country and contributes to obesity, mental health problems, poorer academic performance, reduced graduation rates, and increased risky behaviors.
Standard time facilitates bed and wake times for children allowing them to get the sleep they need. You no longer have to persuade your child it’s actually bedtime when the sun is still high in the sky and daylight is streaming around the edges of the curtains. Waking teens in the morning is easier on ST because the sun will typically be rising, providing the cue needed to get the sleepy teenager up and ready for school. Children will spend fewer days dangerously walking to bus stops in complete darkness. The bottom line is that ST is healthier than DST in terms of sleep, cardiovascular health, weight, cancer risk, alcohol, and tobacco consumption, and improved work and school performance.
What’s next for public policy?
So, what do we do about this? Well, just like having three clocks, we have three choices. Stay on ST, keep DST only in spring/summer/fall, or stay on DST year round. Public consultation by the European Union showed that 84% of respondents were in favor of putting an end to the biannual clock change. Through the years 26 states have considered making DST permanent. The most recent and widely known instance was California Proposition 7 that was passed by voters on November 6, 2018. It gives the California State Legislature the ability, through a two thirds majority vote, to make DST permanent, or go back to ST. House bill 1196 in my home state of Washington recently passed making DST permanent. However, in order for these laws to make DST permanent the Federal Uniform Time Act of 1966 would need to be repealed or changed. This applies to the “Sunshine Act”, which was recently passed in the U.S. Senate, that stipulates the entire U.S. will go to permanent DST in November 2023 (note: this legislation is still awaiting passage by the House of Representatives and the President’s signature).
At the end of the day, sometimes good ideas have a shelf life – like using DST to support the US war effort during World Wars, but not to line the pockets of big business at the expense of personal and public health. The choice of DST is political and therefore can be changed. If I have convinced you of the value of ST, I encourage you to contact your federal and state representatives to let them know where you stand on this issue. By staying on standard time we let nature determine times, not governments. Let’s remember, the importance of the body clock for mental and physical health was acknowledged with the 2017 Nobel Prize in Medicine and Physiology. The sun clock has been the guiding light of our body clock for millennia. Let’s walk the natural path to body clock health by rejecting DST and embracing ST. As thought leader Deepak Chopra said, “No matter how much it gets abused, the human body can restore balance. The first rule is to stop interfering with nature.”