It’s about time to “fall back” again as Daylight Savings Time (DST) comes to an end for this year. Some look forward to the change as “getting an extra hour of sleep” while others dread it getting “dark so early”.
When we think of fall, we often think of nature’s seasonal changes and those of wildlife, such as southern migration, the storing up of food, and winter hibernation. However, humans also display a certain amount of seasonality, even in spite of the impact of industrialization over the last century. While we are no longer ruled by the sun, and our work days begin with blaring alarms and rooms that instantly light up with the flip of a switch, we can still be affected by the changes that come with the fall season.
Daylight savings time creates an artificial change in our social clocks, but not environmental clocks. The sun and moon do not care if we have made a switch to DST or not – they will rise and set according to their own schedule. The resulting rotation of light and dark over a course of approximately 24 hours, creates a circadian rhythm that affects not only people, but also plants, animals, fungi and even bacteria!
Our body’s internal clock uses the daylight to synchronize us to the environment. Research has shown that absent artificial means, the human body will naturally adapt its sleep and activity timing to the seasonal progression of dawn under standard time.
When our social clocks are changed to begin DST in the spring, the body does not automatically make that adjustment immediately. This spring transition is even more difficult for those who tend to fall under the “night owl” category, as compared to their “early bird” friends. However, this same research reveals that both night owls and early birds transition more easily to the release of DST in the fall.
In addition to coordinating sleep and activity levels, the change of seasons affects multiple bodily systems. Photoperiodism refers to the ability of plants and animals to measure the length of days, in order to determine the time of year. This is the innate sense that guides squirrels to gather nuts to store them for the winter, and directs birds to fly south for the winter.
A review of laboratory studies examining the effects of photoperiod on immune function revealed that immune function is enhanced when exposed to shorter day lengths. This remained consistent for every species examined.
However, in humans, short days also led to changes in hormones such as a reduction of prolactin and steroid hormones, along with an increase of melatonin. This is especially important because the secretion of pineal melatonin helps regulate a number of physiological systems, including the brain-gut axis, the autonomic nervous system, and the immune system.
Shorter days are generally accompanied other environmental conditions, such as cooler temperatures, that require additional energy to maintain our body’s temperature status quo. The stress of “coping with energetically demanding conditions may increase adrenocortical steroid levels,” which may in turn compromise immunity. Together, these changes may affect immune function and the development of opportunistic diseases.
A 2017 Danish study published in Epidemiology, evaluated the effects of DST on depression. Researchers examined over 185,000 hospital contacts for unipolar depression from 1995-2012. They compared the incidence rate of hospital visits for unipolar depressive episodes after the transition to and from DST.
Their analysis revealed an 11% increase in unipolar depressive episodes immediately following the fall transition back to standard time. This increase receded back to normal over approximately 10 weeks. They reported that there was no such change associated with the spring transition. They conclude that “Distress associated with the sudden advancement of sunset…may explain this finding.”
How do I Adjust to Changing back to Standard Time?
Fortunately, there are strategies that you can use to help combat the affects of fall’s shorter daylight hours and early sunsets on our mood and energy levels. Chris Winter, M.D., author of “The Sleep Solution” explained to NBC that making a few conscious efforts can make the transition easier:
He offers a few tips:
- Get as much light as possible when you wake up. The light helps your body set its circadian clock. The Sleep Foundation suggests: “consider using a light box or dawn simulator to enhance mental and physical alertness.”
- Exercise in the morning. In addition to exposing you to light, exercise gets you moving and raises your body temperature, which help your body know it’s time to get up.
- Go to bed at your regular time the night before the change, rather than using that extra hour to stay up late without guilt. This will also help your body start getting used to sleeping at the earlier time. The Mayo Clinic suggests you always try to go to bed and wake up at the same time each day.
- Watch out for caffeine. Don’t add in extra caffeine to stay up later, or get up earlier.
To Nap or Not to Nap – that is the question!
Just as some are early birds and others are night owls, some are nappers and some aren’t. Think about how a nap affects your nighttime sleep. If you are can take a short nap and feel revitalized without sacrificing your nightly sleep, then it’s no problem. However, not everyone is a napper.
“This is where people fall off the wagon,” Dr. Winter said. “They’re tired so they nap in the middle of the day, but then when it’s time to go to bed that night or the next night they’re not ready, which can have a bad snowball effect.”
So be honest with yourself. If that 20-minute cat nap will help you, go for it. But if you know that taking a nap will make it hard to go to sleep that night, (or to stay asleep), then skip it. Move around for a few minutes to get the blood pumping. Have a nutritious snack (NOT Caffeine!). Then be sure to go to bed on time and help your body reset.
Regardless of the time of year, sleep is vital to our health. Sleep is the time that your body resets and prepares for the next day. It also plays a big part in regulating many of our hormones, including those that affect metabolism & weight management, stress hormones that play a part in cardiovascular issues and mood. Plus, during sleep, the body releases proteins and other substances that help moderate stress, fight infection and decrease inflammation.
Immediately before and after the transition to or from DST, it is especially important to pay attention to your body and ensure that you are getting the rest that you need for good health.
If you are having trouble sleeping even before the time change or if you feel like your body is not adapting to the change, talk to your doctor of chiropractic at your next visit. Whether you need an adjustment to help your body function optimally, you need to make dietary changes or you need to know what type of pillow is best suited for you, your chiropractor is knowledgeable about what the body needs to be healthy and can assist you in determining what you need to sleep better.
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Pepitone, Julianne. Daylight saving time: 4 surprising health effects of ‘falling back’. Nov. 1, 2018, 1:51 PM CDT / Updated Nov. 2, 2019, 7:32 PM CDT https://www.nbcnews.com/know-your-value/feature/daylight-saving-time-4-surprising-health-effects-falling-back-ncna929546
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