Synch to Your Body’s Own Clock and to Mother Earth for Better Health


In March 2009, Proceedings of the National Academy of Sciences published research done at the Division of Sleep Medicine at Brigham and Women’s Hospital in Boston. Researchers studied 10 subjects – 5 men and 5 women – to see what happened to their cardiovascular and metabolic systems if their behavioral and circadian rhythms were disrupted.

The Cycle of Life

Circadian rhythm is an approximately 24 hour cycle (in humans its actually 25.9 hours) of sleep and wake which is triggered by exposure to light (the day/night cycle) which then triggers cyclic shifts in hormone levels. It is a universal rhythm to which all living things respond – animals and plants. Light is the thing that sets and resets the physiologic changes that occur in the body as a result of circadian rhythm. Humans naturally reset to a 24 hour cycle every day. Circadian rhythm influences sleep/wake, appetite, temperature, activity levels and other bodily functions which were measured in this study.

Behavioral rhythm is one’s daily habits. It’s what time you sleep/wake, eat, work and exercise. One’s schedule may work with or against circadian rhythms. Examples of behaviors that would disrupt circadian rhythms include shift work (working the night shift or rotating shifts frequently), flying across time zones (i.e. jet lag), staying up too late and being unable to wake in the morning, or just following an erratic or unbalanced schedule that disrupts the natural rhythm of life.

Do Disrupted Rhythms Cause Disease?

These researchers proposed: “There is considerable epidemiological [observed] evidence that shift work is associated with increased risk for obesity, diabetes, and cardiovascular disease, perhaps the result of physiologic maladaptation to chronically sleeping and eating at abnormal circadian times.”

To see if they could discover if there was any measurable truth to this observation they took 10 people – 5 men and 5 women – and for 10 days kept them in a laboratory environment where they could disrupt the subject circadian rhythms and normal meal patterns. The first 48 hours the subjects slept and ate at their regular times. On the third day they put them on a “28 hour day” sleeping and waking in a 1 to 2 ratio. They were fed an equal number of calories every 4 hours while they were awake. They did not allow subjects to exercise.

The researchers gathered measurements to compare when the subjects were aligned and misaligned with their normal circadian rhythms.

What They Found Out

The researchers found significant changes when the subjects were out of synch with their circadian rhythms and the more out of synch the subjects were the heightened the body’s response. Here are their measurements:

  • Glucose was 6% higher and insulin was 22% higher when subjects were out of synch. (Even though the body was producing more insulin it was unable to completely control the blood sugar to normal levels.)
  • Blood pressure was 3% higher.
  • Sleep efficiency was 22% lower.
  • Cortisol levels reversed – they went from high on waking and low at sleep time to low on waking and high at sleep time. (Cortisol is the “stress hormone”)
  • Leptin decreased 17%.(Leptin is a hormone produced in the fat cells and when it is decreased it stimulates the appetite/hunger center in the brain and signals there’s an energy deficit in the body.)

So Are You in Synch?

In a world where chronic diseases are epidemic and work/sleep schedules are often erratic, I think this study should be a (pardon the expression) wake up call. No matter how efficient we become, no matter how much technology we have to help us, no matter how our bosses and personal ambitions drive us – there is a natural rhythm to life that deserves respect. Ignored it may one day lead to disease. You can’t fool Mother Nature.

So road warriors and shift workers – take care of yourselves out there. Just because Walmart is open 24 hours, that doesn’t mean doing your shopping at 3AM is a good idea. Know your health risks and attend to them. Connect with your own natural rhythms and the rhythms of the Earth. Whether you’re an early bird “lark” or a night “owl”, try much as you can to keep your behaviors in synch with your body’s own clock and the time and seasons that Mother Earth dictates. As this study shows, it will be path to better health.

How do you handle the stresses of life that throw you off schedule? And what do you do to recover your balance after your body’s clock becomes disrupted?

This information is offered for educational purposes only and is not intended to diagnose, prescribe or treat. For that please seek direct care from a health professional.

Permalink  ·  

Back to the blog home page

page 1 of 1 pages