How to Navigate the Fall Time Change

Here in the U.S., many of us turned the clock back this morning—Sunday, November 3rd. (For those of you who changed last weekend, forgive the lateness of this post for you.)

First, a little nomenclature. The term “Daylight Saving(s) Time” refers to moving the clocks forward an hour in the spring and moving them back in the fall. The term “Daylight Standard Time,” or standard time, is the time when Daylight Saving Time is not in use.

What’s the Big Deal, Anyway? We Gain Back the Hour We Lost.

There’s a myth that moving back into standard time gives you back the hour you lost six months earlier, and offers the gift of extra sleep.

But no matter what you read, the return to standard time can’t be reduced to an extra hour of sleep. This dubious “gift” does the following:

• It brings us sunset—the loss of evening light—a full hour earlier, which today means 4:34 p.m.

• It sets your gastric clock (yes, you have one) off by an hour, which affects digestion

• It makes your normal wakeup time occur an hour earlier, which is tough for those who don’t want to, or can’t, sleep an extra hour

• It pushes your normal bedtime an hour later

When you change the clocks artificially by an hour in either direction, your body’s cues for light, food, and sleep stay the same; they’re synced to the sunlight, and to your brain’s extraordinary and adaptive memory of light-dark, sleep, and eating cues.

The change to clock time, in other words, puts you out of sync.

Let’s look at why that matters, and how you can adapt more fluidly this week by employing a few simple behavioral tools.

The Emerging Science of Chronobiology

The field of chronobiology focuses on the biological and cyclical rhythms in the body and, I’d add, the body’s relationship with time itself. Almost all species have internal rhythms and a sense of time. We have internal circadian (approximately 24-hour) clocks that generate and shape daily cycles in our physiology, emotion, and behavior.

We have ultradian rhythms, too, which occur in smaller time units like two to four hours. Our Basic Rest and Activity Cycles, stages of sleep, hormone secretion, and gastric digestion observe these shorter rhythms—often, in addition to the longer circadian ones.

Most organisms inherit the ability to track time on this 24-hour scale. For example, bees use their clocks to visit flowers at the appropriate time of day so they can feed when flowers are open. Birds use their biological clocks during migration to compensate for the changing position of the sun throughout the day. Other mammals rely on them to forage at the ideal times for avoiding predation.

Your circadian clock is always trying to figure out “when” you are in time--and along with it, how to be in the (cellular) moment.

To be in synchrony with the solar cycle ensures your health, well-being, and survival.

Without contextual information from the outer world, you have a daily rhythm that is closer to 24.2 hours. Getting sunlight adjusts your behavior to a solar day; otherwise, your rhythm would be off--in just five days, for example, you’d be off by a full hour. In one month, you’d be off a full six hours. The effects of being out of sync show up at the level of the cell, the tissue, and behavior.

It turns out that circadian rhythms regulate much of gastrointestinal function, including:

• the microbiome and its balance

• cell growth

• gastrointestinal motility

• intestinal permeability

• intestinal mucosa and immunology

• digestion

• nutrient assimilation

• electrolyte balance

With respect to the above areas of functioning, the GI tract behaves differently during the day when we consume food than it does during the night when we sleep.

Disruption of circadian rhythms, like the kind that both “bookends” of daylight savings time elicits, has negative consequences for all these areas of gut function. In fact, circadian disruption underlies a range of gastrointestinal diseases.

The timing of food consumption wields one of the strongest influences on circadian (~ 24-hour) and ultradian (90-minute to 4-hour) rhythms. In fact, its influence is powerful enough to override the body’s master clock.

Circadian Rhythms + The Body As An Organ of Perception

Homeostasis refers to the way organisms like cells, bodies, and larger systems regulate energy and maintain balance in response to a changing environment. Like interoception, the awareness of signals coming from the body, circadian rhythms are part of homeostasis and therefore essential to survival.  

Here are just a few major functions that span both circadian rhythms and interoception:

• Body temperature, which reaches its lowest point about two hours before awakening

• Gastrointestinal function and the regulation of the enteric nervous system or belly brain

• Gut microbes, which also function on an infradian (4-hour) time unit

• Hormone secretion, including cortisol, which peaks soon after awakening (and also includes blood sugar regulation, and the relationship between Vitamin D3 (a hormone) and melatonin)

• Heart rate and cardiovascular function

• Energy and fatigue

Immune cells also have a clock. Normal immune responses depend greatly on the time of day. Your ability to fight off an endotoxin depends on the time of day you come into contact with it, and the status of your immune system when you do. A time shift like daylight saving puts the body in a pro-inflammatory state, which can worsen heart disease outcome.

The spring shift forward results in less exposure to light in the morning, when we need it most. Morning is also the time when exposure to light impacts cellular signaling and circadian syncing. The time change also results in more light in the evening, when the photoreceptors in our eyes are highly sensitive to light. In the evening, light disrupts the release of natural melatonin in our bodies that would normally promote sleep. (More light in the morning, when the photoreceptors are less sensitive to it, has a less disruptive effect on sleep.) Many of the negative effects of the spring time change are intertwined with the inevitable loss of sleep it augurs. And the out-of-syncness we feel in response to springing the clocks forward lasts a full eight months in the U.S. (It ends in November, when we change the clocks back.)

In an interview with Scientific American, Beth Malow, a professor of neurology and pediatrics at Vanderbilt University, had this to say:

“Most people agree that we need to get rid of this transition back and forth. I personally am an advocate for permanent standard. The reason I am is because I look at light as really important for our well-being, our mood and our sleep. Getting enough light, especially in the winter, is critical. If we have permanent daylight saving time, I worry that come May, June, July, we’re getting too much light too late in the evening. Then we have trouble falling asleep because we don’t make [enough] natural melatonin, which requires it to be dark. To me, the beauty of the permanent standard is: you have your light in the morning in the winter, when you need it, and you have your dark in the summer, when you need it.” 

Time Change and the Enteric Nervous System

The day before the time change this year, sunrise occurred at 7:19 a.m., which meant that my cold immersion therapy happened long before sunrise.

This morning, sunrise happened at 6:24 a.m., which confuses the circadian clock of anyone who walks, dips, swims, runs, or otherwise gets your vitally important outdoor sunlight viewing around sunrise.

My enteric nervous system, or belly brain, is my first-responder to stress (hello, U.S. election cycle) of all kinds. So this is one of the places where, particularly in the fall, I focus my intervention.

I normally practice time-restricted feeding, which means that my first food consumption of the day occurs at 10:00 a.m.

Why is this important? The gut microbiome (think microbes and digestive juices) are released in a rhythmic way in attunement with both 4-hour and 24-hour rhythms. Our sentient and intelligent gut secretes digestive juices prior to when we usually eat—one reason why regular mealtimes are beneficial, because the gut can prepare for digestion.

If I broke fast today at the “regular” time I’ve used for the past six months, doing so would mean that my gastrointestinal clock would have already secreted its microbes and juices an hour beforehand. I’d be eating well after the optimal time to make use of the gut’s intelligent processes.

My intervention: I chose to break fast 20-30 minutes earlier, which meant I could still make use of the gut’s system of preparing for indigestion.

This pattern continues all day; eating the final meal at night would mean that my final meal would occur at 6:30 p.m. clock time, but 7:30 p.m. body time. This can drive digestive issues at the final meal of the day, increasing inflammation just before sleep—when inflammation disrupts sleep quality and quantity.

My intervention: I’ll be eating my evening meal half an hour earlier as well, for two reasons: One, to catch the same “gut preparation” for food that I did at the time of breaking fast.

And two, to minimize the disruption of my sleep time and allow an extra buffer of digestion time before going to sleep, thereby slowing down inflammation.

In case you’re wondering how long it takes for the enteric nervous system to catch up with this change. While we don’t know for sure, we do know that digestive rhythms take more than a day to adjust—especially in someone like meith a history of inflammatory gut issues (IBS).

Tip: For that reason, for the first few days of return to standard time, I’ll have my first meal 20-30 minutes earlier on clock time, which will feel like “normal time” to my gut. This gives my digestive system time to prepare for the food. Similarly, I’ll take my last meal of the day 20-30 minutes earlier on clock time, to maximize digestion.

I’ll also increase my consumption of fermented foods prior to eating. This has historically been a major game-changer. It helps my digestion, and makes for a smooth transition to sleep.

For Humans in Menopause

In a recent workshop on mind, brain, and body health in menopause, I shared research which shows that estrogen regulates circadian rhythms.

For that reason, a loss of estrogen at perimenopause and menopause can slow our adaptability to daylight savings, our capacity to bounce back more readily.

And in this piece on the Musculoskeletal Syndrome of Menopause, I covered the increase in circulating inflammatory molecutes driven by a reduction in estrogen.

Those with underlying conditions—autism, ADHD, other forms of neurodivergence, and neurodegenerative conditions such as Alzheimer’s and other forms of dementia also struggle with the time change.

My take: Neurodivergent people struggle with this more not just because of the disruption in routine, but because our brains pick up on the out-of-syncness, and feel a sense of being “off." And the precipitous drop in estrogen at perimenopause exacerbates this out-of-syncness, and as this piece covers, can aggravate symptoms of ADHD.

Light Viewing in the Return to Daylight Standard Time

In both time change transitions, I view early morning sunlight as close to sunrise as I can, which is also the time I do my cold immersion practice.

In addition, in the fall transition, in order to help my circadian clock adjust more readily, I go for a quick walk at sunset, so my brain registers that it’s getting dark, and begins to release melatonin and with it, promotes better sleep.

This enables me to feel tired earlier, and to get to sleep at least half an hour before the clock says it’s bedtime.

I also increase the length of my pre-sleep wind-down routine, which involves connective tissue work and other therapeutic tools.

I limit my caffeine to less than usual, and take it 20 minutes earlier than normal, with a window after waking so my adenosine sleep pressure molecule receptors don’t have to compete with caffeine to the extent they normally do.

And I minimize bright light in the evenings more than usual, since the photoreceptors at the back of the eyes don’t counter the sleep-inducing impact of melatonin.

This is a lovely time to implement candelight, longer pre-sleep routines, and self-care.

And if you live in the U.S., as I do, what could be a better, more effective way of preparing the mind, brain, and body for the intense process of this week’s presidential election cycle?

Summary of Interventions:

• If possible, wake up ten minutes later until waking up feels easy

• Go to bed 10 minutes later until doing so matches clock time

• have your first meal of the day 20-30 minutes earlier than usual, expanding that window by 10-12 minutes a day later for either 6 or 5 days, respectively, until your “biological” eating time matches clock time

• For the first 5-6 days of the transition, also take your final meal of the day 20-30 minutes earlier, and add an extra 10-12 minutes of waiting time until your biological eating time catches up to chronological dinner time

• View sunlight outside as early in the morning as you can, for 15-30 minutes

• View sunlight at sunset, for 15-30 minutes, for the first 5-7 days

• Expand your pre-sleep routine

• Minimize melatonin-disrupting light in the evening for one week, using candles if possible

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Sources:

Beth Malow, a professor of neurology and pediatrics at Vanderbilt University, had this to say: https://www.scientificamerican.com/article/governments-worldwide-consider-ditching-daylight-saving-time/

It alters gene expression in cardiac myocytes: Martino, T. A., Tata, N., Belsham, D. D., Chalmers, J., Straume, M., Lee, P., Pribiag, H., Khaper, N., Liu, P. P., Dawood, F., Backx, P. H., Ralph, M. R., & Sole, M. J. (2007). Disturbed diurnal rhythm alters gene expression and exacerbates cardiovascular disease with rescue by resynchronization. Hypertension (Dallas, Tex. : 1979), 49(5), 1104–1113. https://doi.org/10.1161/HYPERTENSIONAHA.106.083568

Alters the epigenetic profile of core clock genes: Malow, B. A., Veatch, O. J., & Bagai, K. (2020). Are Daylight Saving Time Changes Bad for the Brain?. JAMA neurology, 77(1), 9–10. https://doi.org/10.1001/jamaneurol.2019.3780

Increases inflammatory markers: Wright, K. P., Jr, Drake, A. L., Frey, D. J., Fleshner, M., Desouza, C. A., Gronfier, C., & Czeisler, C. A. (2015). Influence of sleep deprivation and circadian misalignment on cortisol, inflammatory markers, and cytokine balance. Brain, behavior, and immunity, 47, 24–34. https://doi.org/10.1016/j.bbi.2015.01.004

Lowers vagal tone: Grimaldi, D., Carter, J. R., Van Cauter, E., & Leproult, R. (2016). Adverse Impact of Sleep Restriction and Circadian Misalignment on Autonomic Function in Healthy Young Adults. Hypertension (Dallas, Tex. : 1979), 68(1), 243–250. https://doi.org/10.1161/HYPERTENSIONAHA.115.06847

Circadian disruption underlies a range of gastrointestinal diseases: Voigt, R. M., Forsyth, C. B., & Keshavarzian, A. (2019). Circadian rhythms: a regulator of gastrointestinal health and dysfunction. Expert review of gastroenterology & hepatology, 13(5), 411–424. https://doi.org/10.1080/17474124.2019.1595588

One of the strongest influences on circadian rhythms in the intestine is the timing of food consumption: Konturek, P. C., Brzozowski, T., & Konturek, S. J. (2011). Gut clock: implication of circadian rhythms in the gastrointestinal tract. Journal of physiology and pharmacology : an official journal of the Polish Physiological Society, 62(2), 139–150.

the GI tract behaves differently during the day: Hoogerwerf W. A. (2009). Role of biological rhythms in gastrointestinal health and disease. Reviews in endocrine & metabolic disorders, 10(4), 293–300. https://doi.org/10.1007/s11154-009-9119-3

Researchers think that disruption of circadian rhythms compromises gastrointestinal motility: Yamaguchi, M., Kotani, K., Tsuzaki, K., Takagi, A., Motokubota, N., Komai, N., Sakane, N., Moritani, T., & Nagai, N. (2015). Circadian rhythm genes CLOCK and PER3 polymorphisms and morning gastric motility in humans. PloS one, 10(3), e0120009. https://doi.org/10.1371/journal.pone.0120009

disruption in our circadian rhythm can have a negative impact on intestinal barrier function: Summa, K. C., Voigt, R. M., Forsyth, C. B., Shaikh, M., Cavanaugh, K., Tang, Y., Vitaterna, M. H., Song, S., Turek, F. W., & Keshavarzian, A. (2013). Disruption of the Circadian Clock in Mice Increases Intestinal Permeability and Promotes Alcohol-Induced Hepatic Pathology and Inflammation. PloS one, 8(6), e67102. https://doi.org/10.1371/journal.pone.0067102

Studies also demonstrate that circadian disruptions alter the gut microbiome: Voigt, R. M., Forsyth, C. B., Green, S. J., Mutlu, E., Engen, P., Vitaterna, M. H., Turek, F. W., & Keshavarzian, A. (2014). Circadian disorganization alters intestinal microbiota. PloS one, 9(5), e97500. https://doi.org/10.1371/journal.pone.0097500. See also: Voigt, R. M., Summa, K. C., Forsyth, C. B., Green, S. J., Engen, P., Naqib, A., Vitaterna, M. H., Turek, F. W., & Keshavarzian, A. (2016). The Circadian Clock Mutation Promotes Intestinal Dysbiosis. Alcoholism, clinical and experimental research, 40(2), 335–347. https://doi.org/10.1111/acer.12943

estrogen regulates circadian rhythms: Alvord, V. M., Kantra, E. J., & Pendergast, J. S. (2022). Estrogens and the circadian system. Seminars in Cell & Developmental Biology, 126, 56–65. https://doi.org/10.1016/j.semcdb.2021.04.010