Every cell in your body responds to an internal clock, kind of like how you plan your day around a schedule. Researchers are beginning to learn how our internal rhythms affect every aspect of our health and well being.
According to 2017 Nobel Laureate Michael Young, MD:
"We didn't realize at the time that this clock would be represented all over the body in many different tissues and control so many different biological processes that we go through every day. It left us with the understanding that our whole body is rhythmically active."
Young won a shared Nobel Prize in Physiology and Medicine for 2017. One topic he explores is the health implications of our circadian rhythms. He explained in an interview published in The Scientist that the modern lifestyle where people skip sleep, skip meals, and eat at random times is taking a toll on people's health,
"These are things that will disrupt that rhythmicity, that coherent rhythmicity throughout the body. And from experiments ongoing in animals, model organism studies, all of these things produce deficits in health." said Young.
How Circadian Rhythm Affects You And Your Biometrics
Young isn't the only scientist researching the consequences of allowing today's lifestyle to disrupt our natural circadian rhythms.
“You can think of the cell cycle as being driven by a clock in the same way you think of heart rate or sleep patterns being driven by clocks,” said James Ferrell, MD, PhD, of Stanford University. Ferrel is a professor of chemical and systems biology and biochemistry.
According to Ferrell, human cells operate on a 24-hour cycle. The optimal times for sleep, activity, healing, and eating are all tied to these cycles and to our circadian rhythms. Scientists are only beginning to understand the consequences of breaking or disrupting these cycles. Leading researchers believe embracing and respecting our natural rhythms may have many benefits including:
- Improved longevity and possibly slowing the aging process
- More energy during the day and restful sleep at night
- More productive and creative working hours
- Better weight control and less metabolic diseases when activity, exercise, hydration and nutrition fits within the right phases in our circadian rhythm
- Improved body chemistry and improved biometrics. Numerous studies note that Heart Rate Variability follows circadian rhythms.
Of course, further research is needed. Fitness expert and popular TED talk presenter Pam Peeke, MD recently presented a roundup of relevant research at the 2018 IDEA World Nutrition and Behavioral Change Summit. Peeke authored bestselling books including "Body For Life For Women" and "Fit To Live."
"Respect the clock," said Peeke, " Respect your cells."
Making the Most of Your Circadian Rhythm
Circadian rhythms determine our best sleeping and waking cycles. Our natural cycle revolves around Earth's cycle of daylight and darkness.
The blue light from the sun serves as a prompt to remind us it is daytime and time to wake. Since the sun is our biggest source of blue light, this worked for centuries. However, in recent years LED lights, computer monitors, smartphones, and flat screen TVs also provide blue light sometimes late into the night. This may be why so many people find it hard to get to sleep after late night binging on YouTube or working late to meet a deadline.
These same rhythms also control our energy cycles throughout the day. A February, 2018 article in the Wall Street Journal summarized how circadian rhythms affect productivity throughout the day. These phases are common, but vary a little depending on whether you are a morning person or a night owl. The phases include:
- Peak: Our peak productivity usually runs from waking to mid-afternoon (usually around 3pm). During this time we are our most alert and excel at analytic work.
- Trough: Have you ever felt drowsy a few hours after lunch? Did that feeling last until around 5pm? This is the "Trough" when natural alertness and productivity declines. Researchers advise that we avoid major decisions and spend that time catching up on busy work and administrative work. Surprisingly some athletes set personal best records during this period, so late afternoon might be a good time for you to squeeze in a workout. This is also the perfect time for a 20 minute power nap if your schedule allows it.
- Rebound: Energy levels improve sometime after 5pm. This second wind typically lasts until around 9 pm. Many people find they do their best creative work as they feel less mentally inhibited. Our bodies prepare for rest and sleep after the rebound as hormones signal it is time to wind down.
- Sleep and recovery: While we rest, our cells repair. Autophagy refers to our cells process to repair damage from life's stresses. Our best autophagy tends to happen hours after our last meal and while we sleep, according to Peeke. Several researchers are exploring how a 12 - 16 hour intermittent fast may facilitate more optimal autophagy. Although several researchers saw promising results in the lab, the topic requires further exploration.
Peeke suggested we prioritize sleep so we return to a more natural cycle of going to bed shortly after winding down from our Rebound period and we sleep for the recommended 7 - 9 hours that the Sleep Foundation recommends for adults.
Since blue light appears to disrupt the signals that prepare us for sleep, we should try not using devices at least an hour before bedtime. At the very least, try the night mode which uses an orange light. According to a study, just one hour of blue light exposure at night may disrupt sleep by signalling our body's waking process. Soft lighting, like 30 Lux or less, simulates moonlight and candlelight that inspires sleep and relaxation.
In addition to restful sleep, other factors that help us move towards natural circadian rhythms include:
- Regular physical activity including planned fitness building workouts to maintain our cardiovascular systems, mobility, and muscular strength.
- Enjoy healthy, balanced nutrition. Consider enjoying your dinner in the early evening to allow your body time to repair through autophagy.
- Seek natural light during the day. Bright light measuring at least 2,000 Lux helps reset our circadian rhythms to recognize daytime. You can use a free camera light meter app, like Lux Camera, to estimate available light during the day.
- Take time for relaxation or meditation to help you wind down.
Does all that sound familiar? These healthy lifestyle choices impact your biometrics including your heart rate variability and blood pressure. It shouldn't be surprising they also help regulate your circadian rhythms.
By embracing your natural rhythms, you may find improved sleep at night and improved energy during the day. These tips may also help improve or maintain healthy biometrics and a healthy body.