It’s well known that night shift-work can increase the risk of obesity, heart attack, diabetes, and breast cancer. But several common daily habits can mess up your biological rhythms as well. How well is your biological clock ticking? Is it off and dragging, as it is for many folks living in the unnatural and ever-faster modern lane of life?
Late Nights, Bright Lights, Electronic Screens, Jet Lag…
For many, lifestyle includes bright lights at night, cross-currents of electromagnetic fields, constant exposure to electronic screens, keeping late hours, shift-work, or hopscotching business trips by jet from one part the world to another.
As a result, more and more people are developing so-called “circadian disruption,” a disorder undermining our internal biological clocks and physiological rhythms, and, ultimately, our health.
The risks were put in focus in a 2014 article in The Wall Street Journal by Gene Block, the chancellor of UCLA and a professor of psychiatry and biobehavioral science. Dr. Block points out that many people understand such disruption in terms of jet lag, when you cross multiple time zones, but the phenomenon goes well beyond long-distance travel. Circadian disruption can occur as a result of many lifestyle habits that are commonplace for many in today’s culture.
The circadian rhythm refers to the 24-hour cycle of hormonal patterns based on a natural sequence of light and dark, and rest and activity. The cycle programs your internal clock and affects the activities of hormones, cells, tissues, and organs. Throughout virtually all of history, human activity operated on this natural cycle.
However, that is increasingly less so today.
People today are active into the night, and some throughout the night because of their work. Bright lights illuminate nocturnal activities. Masses of people spend their evenings, and often beyond, staring into gleaming TV, tablet, computer, and cell phone screens. The “burning of the midnight lamp” is not just a Jimi Hendrix classic. It is a way of life for many.
According to Dr. Block, this switched-on lifestyle contributes to circadian disruption that can lead to serious diseases, including type 2 diabetes, various cancers, suppressed immune function, cognitive deficits, and premature aging.
Clearly, as humans violate the basic law of Nature regarding rest and activity we put ourselves at risk and add additional stressors to life. Whatever the violation, whether it’s job-related or elective staying up late with a computer, modern lifestyle and habits endanger the wondrously precise rhythms and machinery of the body.
Common disruptors include tablets and computers. In 2013, experts (Wood B, et al.) at the Lighting Research Center at Rensselaer Polytechnic Institute showed that two hours of laptop or tablet use before bedtime can suppress melatonin, a primary circadian hormone involved in promoting sleep.
This habit, the researchers say, will set you up for sleep disturbances, and other problems. Young adults and adolescents who tend to be night owls need to pay heed here.
Technology developments have led to bigger and brighter screens, says Brittany Wood, one of the researchers. “To produce white light, these electronic devices must emit light at short wavelengths, which makes them potential sources for suppressing or delaying the onset of melatonin in the evening.”
Returning to the jet lag issue, it is interesting to note that researchers in Israel (see Oaklander) have produced fascinating findings indicating that the circadian disruption triggered by night-shift work and jet lag may contribute to diabetes and obesity by disturbing the beneficial bacteria residing in the gut.
“These microbes were completely messed up,” the researchers said.
That is no small thing because the friendly bacteria in your intestines – including familiar names like lactobacillus acidophilus and bifidabacteria – are pivotal to intestinal and immune function.
Remedies to Protect Your Circadian Rhythm
What can you do to protect your circadian rhythm? Here are some obvious and less obvious recommendations:
- Stay off your computer or tablet before bedtime. If you can’t avoid it, try not to go over two hours. Dim the screen as much as possible.
- Don’t watch late news or sports at night. News is full of stress. Sports events get you revved-up, especially if you are a fan of a particular team. Research (Figueiro MG) shows, however, that the light from televisions does not impact melatonin levels in the evening.
- Settle in, wind down. Try to use your time before bed for activities that defuse a stressed and agitated mind − for example, meditation, prayer, or listening to soothing music.
- Go to bed no later than 11:00 p.m. Ideally, try to be in bed by 10:00 p.m., and try to be consistent with your bedtime. For virtually all of history, we went to sleep early and got up early. We were attuned to Nature. Almost twenty-five hundred years ago, the philosopher Aristotle said, “It is well to be up before daybreak, for such habits contribute to health, wealth, and wisdom.” More familiar and recent is the Benjamin Franklin version: “Early to bed and early to rise, makes a man healthy, wealthy, and wise.” Obviously, this is a time-tested formula.
- Eat lightly or not at all in the evening. Late, heavy meals do not support your biological rhythm trying to downshift at night. Refined sugar is a particular no-no. It can trigger an insulin response and energy spike likely to result in serious tossing and turning. If you get hungry in the late evening, have a glass of warm milk. Milk contains tryptophan, a calming amino acid.
- Keep your bedroom free of light sources. In order for the proper production of the sleep inducing hormone, melatonin, you need to be surrounded by darkness.
- Earthing (grounding). Earthing means connecting to the Earth’s natural, gentle energy by either being barefoot outdoors or in contact with conductive bed sheets and mats indoors on a regular basis. Earthing is creating a big buzz in the health world. Among other things, it can calm the nervous system, reduce inflammation and pain, promote blood flow, and help normalize the natural circadian pattern of the stress hormone cortisol often out-of-sync. One good way to deal with jet lag is to walk barefoot on grass or concrete for at least 20 minutes or so as soon as possible after flying over multiple time zones. Doing so, helps to align your biological clock with the local time zone.
- Minimize ambient electromagnetic fields (EMFs). Some people are disturbed by electric fields radiating from appliances and wires in the wall close to the bed. These fields can sometimes trigger sleep disturbances. Best to remove computers, radios, electric clocks, and TVs from the bedroom or at least keep them at a distance from where you sleep. Unplug − not just turn off − the lamp next to the bed. Some people who are highly sensitive to electromagnetic fields, or who have children with compromised health, may want to turn off the electricity in their house at night. Earthing, which I just mentioned, can eliminate voltage induced on your body from wiring and common alternating current appliances.
- Block GD. “Our Internal Sleep Clocks Are Out of Sync: the new science behind the disruption brought by jet lag, unusual hours and bright tablet screens.” The Wall Street Journal, August 14, 2014.
- Wood B, et al. Light level and duration of exposure determines the impact of self-luminous tablets on melatonin suppression. Appl Ergon. 2013;44(2):237-40.
- Lighting Research Center. Depending on How Much and How Long, Light from Self-Luminous Tablet Computers Can Affect Evening Melatonin, Delaying Sleep.
- Oaklander M. “How Jet Lag Can Contribute to Obesity.” Time.com, Oct. 16, 2014. Published online at
- Figueiro MG, et al. The impact of watching television on evening melatonin levels. J Society for Information Display. 2013;21(10):417-421.
- Thaiss CA, et al. Transkingdom control of microbiota diurnal oscillations promotes metabolic homeostasis. Cell. 2014;159(3):514–529. Published online at
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