Ask the Pharmacist

Q: In one of your previous Ask the Pharmacist columns, you mentioned the term circadian rhythm. Can you explain what circadian rhythm is and how it affects our body?

A: Circadian rhythm is the regular process your body experiences over the course of a 24-hour period. All of us have a master circadian clock (some call it a circadian pacemaker) that is situated in the hypothalamus part of our brain and helps our body to know when it is time to sleep and awaken.

This master clock is highly influenced by light. As light enters our eyes, even when our lids are closed, it messages our internal master circadian clock to stop producing melatonin (a hormone that encourages sleep) and we slowly begin to awaken.

Our circadian rhythm also controls other hormones, such as cortisol, which is required for the energy our body needs to function. In addition, it helps regulate our digestive system and the timing of our meals, as well as helping to regulate our body temperature which changes over the course of the day.

You may have noticed that among the people you know, perhaps even in your own household, there is a wide variation in sleep and wake times. Often, this is dependent on the age of the individual.
It is interesting to learn that we are not born with a circadian rhythm that is set up and ready to go. That explains why the sleep and awake times of babies are so erratic, making it challenging for the parent(s) in the early days until the babies' master circadian clock can be developed which can take a few months.

The body begins to produce the hormone, melatonin, around the age of three months while the hormone, cortisol, gets developed anywhere from two months to nine months of age.

Once the circadian rhythm is established, you will notice the beginning of a regular sleep-and-wake pattern developing and allowing for nine to 10 hours of sleep at night, often with a bedtime routine that is early in the evening. Parents look forward to their babies circadian rhythm so they, too, can get some good rest.

Let us delve further into the various circadian rhythm disorders and why that may be.

Delayed Sleep Phase Syndrome:

When our children enter the teen years, there appears to be a sleep phase delay, meaning that their normal circadian rhythm does not respond to the previous early bedtime. Rather, the natural melatonin level in the body, which induces the sleep phase, may not increase until 10-11 p.m. To get the suggested nine to 10 hours of sleep for the teens, they tend to sleep in later to compensate.

You may have noticed how difficult it can be to get your teenagers up for school. We have heard many thoughts over the years that high school should change their schedule to meet the best productivity of the teenage circadian rhythm.

As these teenagers transition into young adults, it is suggested they still aim for seven to nine hours of sleep each night. Some people may be more apt to sleep and wake earlier while others may choose to sleep and wake later. Either of these scenarios is fine, providing you feel you have a consistent, healthy sleep habit and have no trouble waking up in the morning at a set time when the need arises and no trouble going to sleep at a set time to allow getting a sufficient amount of sleep.

Advanced Sleep Phase Disorder:

As mature adults (ahem, we prefer to think of the “older” adults as mature), many notice that our circadian rhythm shifts to an earlier bedtime and earlier wake time. This is a normal experience of aging and you should not be concerned as long as you are able to maintain consistency of sleep time.

Jet Lag:

With many people travelling around the globe freely and easily (although not as freely and easily in recent weeks), when you cross three or more time zones, you may experience a fluctuation of your circadian rhythm, leading to insomnia (an inability to sleep) and overwhelming fatigue.

Shift Work Sleep Disorder:

There are many jobs/professions that expect us to work a shift that is not in the typical daytime hours. Some examples of such professions are health-care workers, maintenance workers, nuclear facility workers, among others. It would be one thing if your unusually-timed shift was continually the same and consistent. But more than likely, people change their shift every few days or weeks and have to adjust to a new schedule, only to change again in another few days or weeks.

When our circadian rhythm is altered, it can affect the body in many ways. Since we know that our master circadian clock influences many parts of our body, it shouldn’t come as a surprise to learn it can negatively impact our hormones, our digestion, our body temperature, our energy levels and may affect our ability to fight infections, and impair our memory.

Other than the obvious of travel or shift work causing disruptions to our circadian rhythm, other reasons that can affect it are:
 

• Damage to our brain (stroke, head injury, dementia)
• Blindness (since not getting triggered by light)
• Medications
• Being bedridden

Symptoms of Circadian Rhythm Sleep Disorders

You may not be surprised to learn that if you do suffer from a circadian rhythm sleep disorder, you may feel tired during the day which may also lead to difficulty concentrating with a heavy or foggy feeling and an inability to think clearly. For some people, the desire to sleep is so strong that they may resort to alcohol, cannabis, and/or sleep-aid medications to help them fall asleep. Those products combined with the poor sleep, may lead to daytime drowsiness and, therefore, people may reach for stimulants to help them stay awake. These stimulants, if consumed later in the day to help you function, can wreak havoc for you when you are trying to sleep later that day. And so the vicious cycle continues.

Recall from earlier that our circadian clock is also linked to other body functions, including, but not limited to, our hormones, body temperature and our digestive system. Thus, a circadian clock disruption may leave you feeling out of sync, with feelings of nausea, irritability, depression, and a general feeling of being unwell. This may also lead to an increased risk of heart or metabolic disorders.

Our next column will review how you might correct circadian rhythm disorders and get back to getting a good night sleep.

For more information about this or any other health-related questions, contact the pharmacists at Gordon Pharmasave, Your Health and Wellness Destination. Also check the website at www.gordon-pharmasave.com/ and the Facebook page at www.facebook.com/GordonPharmasave/.