Asleep at the wheel? Learning about our body clock or “circadian system”; An interview with Dr. Vidafar

Have you ever had to stay up all night, or work nights instead of days at your job?

You probably felt tired, sluggish, and in a bit of a fog for one or more of the days that followed. The behind-the-scenes toll and aftereffects those disruptions in your schedule had on your body are rooted far below the surface.

Are you familiar with what many call “the body clock?”

Your day-to-day schedule, your environment, and habits constantly communicate with your body’s circadian system. The circadian system is the “master clock” of each individual human body and it plays one of the biggest roles in your health and wellness.

“It is the core clock that keeps all the other clocks in our bodies synchronized,” said Dr. Vidafar. “Our organs have their own body clock and they are all governed by this master clock.” The human body is complex, to say the least.

Tiny but mighty, our body clock “is about the size of a pinhead and there are about 20,000 neurons in it,” said Dr. Vidafar. “This clock has its own roughly 24-hour window.”

It’s interesting to know that sleep is categorized as a behavior. “Sleep is really just an output of the clock itself,” said Dr. Vidafar. Sleep is imperative for our bodies.

I know when my sleep schedule is thrown off, the days that follow are quite challenging in many facets.

We know the toll it can take on our bodies, such as moodiness, lethargy, and brain fog.

Let’s roll back the literal clock a handful of decades…

For example, Dr. Vidafar said, in studies during the 1970s, scientists would “keep people up for ridiculous amounts of time.

What was the result?

This in turn led to “the deterioration of mental wellbeing and metabolic wellbeing.”

The devastation of lack of sleep permeates the entire human body.  How much so? One extreme example is the use of sleep deprivation as a form of torture when military and other agencies have interrogated prisoners during war time, hoping to get them to divulge secret information. Those subjected to this, commonly experienced symptoms such as confusion, depression, and fatigue.

The astounding danger of sleep deprivation was solidified when the United States enacted a law which defined sleep deprivation as an illegal form of torture. The United States has indeed prosecuted military officials for these tactics. Sleep deprivation was used in World War II (in Japanese POW camps and commonly favored by the KGB).

In the 1960s, studies were performed in mines and participants would be left in caves without any external cues, such as light. “They were able to determine [when] their body temperature increased or decreased, their cognitive functions had peaks and troughs; the study determined the circadian clock itself does not need cues from the environment. It kind of just oscillates on its own,” Dr. Vidafar said.

My paternal grandfather and great-grandfather worked in the Pennsylvania coal mines from the 1910s through 1930s. They were not part of a study or experiment. They were just trying to earn a living. My grandfather was buried underground in a mine collapse for 10 days.

Fortunately he survived, but the repercussions were coal workers’ pneumoconiosis, commonly known as black lung disease, a broken back, and numerous other traumatic injuries. He spent a year in the hospital to make substantial enough progress and recovery to go back home. Life was never really the same. The disabilities he incurred in the mining environment stayed with him until he passed away.

If we remove artificial light from the scenario and think back to how our early ancestors were living – as Dr. Vidafar explained, “it becomes a lot clearer why there is this interesting circadian rhythm and also why if there’s something that goes wrong with [it] it will have effects on all the other rhythms in your body.”

Siblings, a neighbor, your spouse – each of us have varying degrees of vulnerabilities and sensitives to light or the lack thereof. If a study was performed on your immediate family and close friends, I think you would be astonished to learn the varying levels of effects and tolerances.

Dr. Vidafar said it’s interesting “just how varied individuals are to the same light source.”

Dr. Vidafar lives by what she learns in research. She said that the “more you are able to kind of align your behavior to what is going on in your immediate world, keeping your light / dark cycle as close to what is going on outside [you’re] minimizing any kind of susceptibility to mood and sleep disorders.”

“We know the length of light that you are exposed to can impact how much melatonin is being released during the night,” said Dr. Vidafar. Melatonin is a hormone made by the body that helps control the body’s sleep cycle. Once again, it goes back to staying in the present; staying aware of helping yourself.

Various things affect the body’s clock. Dietary-wise, Dr. Vidafar said, “Food is a cue to the circadian system.”

When you wake up at 2am what is your next move?  Bathroom? Kitchen?  Roll over and try to fall back asleep?

Your decision may make all the difference.

If you are a person who wakes up unplanned, at say 1 a.m., goes to the kitchen, opens the refrigerator (exposing yourself to artificial light), and consumes a few snacks – you’ve basically just told your circadian (body clock) system, “We are awake now, [please] deal with this issue.”

These disruptions impact everything, mental and physical. “If you’re giving [your body] cues to stay awake, when really what it’s trying to do is promote sleep and suppress the mood to eat, you’re miscommunicating; you’re giving it false information that it’s awake, even though its night outside,” said Dr. Vidafar.

Do you know what serves as a messenger in our body?

Hormones serve as our body’s “chemical messengers.” The endocrine system is “a series of glands that produce and secrete hormones that the body uses for a wide range of functions.”*

Our growth, respiration, metabolism, sensory perception and reproduction are just some of the bodily functions that are controlled by the endocrine system. The endocrine system is “heavily regulated by the circadian system,” Dr. Vidafar said.

The past few years there has been an ever-increasing focus and attention on the impact that light-emitting devices have on our wellbeing.

What role does light really play when it comes to sleep?

We’ve seen technology companies provide light adjustments for devices and some companies even provide more comfortable work environments for employees. This is definitely a step in the right direction.

As I’ve said in previous posts, I minimize device use once dusk hits. Dr. Vidafar said it’s important to observe time to wind down before one’s desired bedtime. She said it’s preferable to stop using light-emitting devices one hour before retiring to bed. She said that one hour “is an adequate rule of thumb,” although “someone super sensitive to light might need 3 to 4 hours” without light-emitting devices before bed.

Dr. Vidafar said the light most humans want to absorb is the morning light as it’s like a “hard reset” to the body, but “afternoon light is better” for elderly and individuals who suffer from certain mood disorders (bipolar), Dr. Vidafar said. As you may have guessed, “As we age, our circadian system becomes earlier and earlier,” she confirmed.

Take three generations of your family, perhaps a newborn, mother, and grandfather– melatonin is like a wave – from non-existent to high and then taking a dip back down.

Dr. Vidafar explained the variability, “Before the age of 3 months we don’t even produce melatonin. The circadian system hasn’t really developed. From the age of 1 to 3 years that’s when the peak melatonin concentration occurs.”

We commonly hear that the first 3 years of a child’s life determines so much (personality for one). Dr. Vidafar said that “during that age, [a human] will produce the most melatonin overnight than any other age.”

“For every decade after, your melatonin gradually declines, so by the time you are 70 to 80, you might be secreting a lot less melatonin,” Dr. Vidafar said. “Again, individual differences play a role.”

What’s the best way to set yourself up for a good night’s sleep?

Most importantly, for best health, Dr. Vidafar said that at night, “We need to be winding down and ready for sleep. We need to embrace the dark at night; that’s what we evolved to do.”

I personally have found immense benefits in following her advice. I feel comfortable and relaxed by embracing the dark. Dr. Vidafar confirmed, “Dark environment calms the system” and a person needs to be calm to fall asleep.


Dr. Vidafar works in the Department of Psychiatry and Sleep and Circadian Research Laboratory at University of Michigan. Vidafar, who is widely published, has dedicated her time and expertise to helping others understand the body’s circadian system and those who suffer and/or have vulnerabilities pertaining to light, sleep, and mood.

Coming next: Migraine patients can start healthy walks with baby steps

Please consider sharing this article with family, friends, neighbors, coworkers.  Let’s help each other reach optimal health.



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