Your internal clock. Not your biological clock, which is completely different, but the circadian or sleep rhythm, the little clock inside that tells you when you should be sleeping and when you should be active. While we’ve all been told that we need seven to nine hours a night, or have felt the impact of waking up in the dark vs. on a sunny morning, how exactly does our circadian rhythm work, and how does it impact our overall health? We consulted with Human Sleep & Circadian Physiology expert Dr. Lederle to hear what she had to say.
WHAT IS CIRCADIAN RHYTHM, AND HOW DOES THE CIRCADIAN SYSTEM WORK?
“Think of it like an orchestra,” says Dr. Lederle, “The [circadian] master clock is the conductor and the peripheral clocks are the musicians. The role of the conductor is to set the beat, the rhythm, and to tell each musician when to play. Musicians may play alone or together in groups.”
To put it scientifically, a circadian rhythm refers to the body’s 24 hour cycle (also known as your sleep/wake cycle). Though it can be influenced by external factors such as light and temperature, it is ultimately controlled by the hypothalamus, a small part of the brain near the pituitary gland. Circadian rhythms are subject to change depending on age and function best when we stick to a regular sleep schedule that our bodies can adjust to.
However, like an orchestra, when there isn’t someone directing them when to play, things can quickly get out of synch, as Dr. Lederle eloquently puts it: “When there is no conductor, musicians will play when they think it is their turn and what should be a beautifully symphony quickly becomes a cacophony. Like a conductor, the master clock sets the time for the body and for all the various processes and functions and aligns them. It makes sure that the liver and the stomach for example know when they each need to function and when they can rest.”
If there is no master clock or conductor, our body doesn’t know when to sleep and when to wake, leading to illness over time, such as issues with gut health, obesity, and even cardiovascular disease, according to Dr. Lederle.
CIRCADIAN SYSTEM AND AGE
As mentioned, age plays a role in how our sleep/wake cycles. Just consider the amount of sleep you needed as a baby or as a child compared to the amount you need as an adult. But don’t mistake the fact that you can function as an adult on less sleep than you did as a child. Studies have shown that adults who do frequently do not follow a healthy circadian rhythm can experience a decrease in cognitive function over time.
That being said, a desire to go to bed earlier and wake up earlier isn’t a signal of cognitive decline, but rather, a natural part of aging. “These changes appear to be part of normal aging,” says Dr. Lederle, “For example, we find that melatonin levels, a hormone used by the clock as a signal for nighttime, are lower in older people. Wake time also changes so that older people wake up earlier and go to bed earlier.”
WHEN OUR CIRCADIAN RHYTHM GETS OUT OF SYNC
Overall, it’s safe to say that our bodies like routines. We call using the bathroom at the same time each day being “regular,” and feel our best when we are eating approximately the same amount each day at similar intervals, exercising regularly, and getting the amount of sleep our bodies have come to expect. So what happens when we go off-road and completely disregard routines?
“Living against the rhythm your clock has set and repeatedly changing the pattern of your light exposure (when day starts and ends that is) thereby causes a mismatch between your inner clock and the timing of the outside world, increasing the risk for health problems,” explains Dr. Lederle. “Metabolic problems, cognitive problems and mood problems increase when we live against our inner clock.”
In the case of our gut health, scientists have noted that our microbiota, or gut bacteria, rely on circadian rhythm to determine when they’re in a period of fasting or feeding. When our circadian rhythm gets out of synch, so too does our gut microbiota, which can cause an imbalance of gut bacteria that can put us at a higher risk for metabolic diseases such as diabetes and obesity. Taking a prebiotic and probiotic regularly can help to keep the bacteria in balance in the short-term, while you work to get back on a proper sleep schedule.
While getting out of synch can cause those more serious problems, it’s important to note also that it often gets out of synch simply due to travel:
“A well-known misalignment between our internal rhythm and the external light-dark cycle is jet lag,” Dr. Lederle says. “When you travel across time zones, the timing of the light coming on so to speak changes – it will be earlier if you travel to Australia and later if you travel to the United States. Your master clock is now faced with catching up with this change in timing. Usually it takes a number of days (depending on which direction you travel and how many time zones your cross, roughly speaking it is one hour of shift per day).”
If you’ve just experienced a time zone change and are experiencing nausea, alterations in mood, difficulty concentrating, chances are that your circadian rhythm is trying to adjust to its new sleep/wake cycle. “Your clock is giving time signals to the body as usual, but they don’t make sense in the new light-dark cycle that you are in,” according to Dr. Lederle. But don’t take jet lag lightly: “Your liver can adapt much quicker to the new light-dark pattern because apart from listening to signals from your master clock, is also uses the timing of your meals as signals when it needs to work and when it can rest. Because the liver decides to follow a different cue than let’s say the heart, these two organs become misaligned and that has the potential to contribute to disease.”
HOW DO I KEEP MY CIRCADIAN SYSTEM HEALTHY WHEN TRAVELING?
The first thing is to have your body adjust to the new system as quickly as possible. That means lining up sleep with the natural night and day cycles of your new setting, and also eating on the same cadence as those in the time zone. If you find that you arrive at a time that is a normal meal time for you, but isn’t for where you are, aim to fast instead of eating immediately.
To help your body fall asleep at a new time, try out our SLEEP DROPS. This alcohol-free, non-habit forming formula works to help you fall asleep and stay asleep naturally, so your body clock can adapt. Or, if you’re looking for an energy boost when you arrive, check out POWER UP, an all natural caffeine boosted sourced from Brazilian guarana.