The Importance of Circadian Rhythm for Health: Why Your Body Clock Matters

Over the years, indoor living has evolved significantly. Our homes have become sanctuaries of comfort that have everything we need.  We work, play and socialize indoors. Yes, maybe we go for a walk here and there to get some “fresh air” but, realistically, we spend most of our time indoors.  Our modern, indoor way of living is devastating to the natural rhythm of our bodies. 

One of the most crucial, yet often disregarded, aspects of our biological makeup is our circadian rhythm. This natural, internal clock operates on roughly a 24-hour cycle and has a huge impact on different physiological processes, including sleep-wake cycles, hormone release, neurotransmitter modulation, and even our metabolism. Understanding and honouring our circadian rhythm is fundamental to optimizing our health and well-being.

What is Circadian Rhythm?

Light is essentially the time-keeper of our bodies. We respond primarily to light and darkness in our environment.   This is true for all living organisms, including animals, plants, and even microbes (think gut health). We have a “master clock” know as the SCN (suprachiasmatic nucleus) that takes cues from our light environment and coordinates things like body temperature, hormone levels, and neurotransmitters which, in turn, tell our cells when to perform certain tasks that affect our sleep, energy, digestion, mood, metabolism.

Things like hormone imbalances, mood disorders, and cortisol issues start with light, and our modern indoor way of living disconnects us from that vital information. Sunlight and darkness are vital for our health and vitality and limiting sunlight has been shown to increase rates of disease.

Just A Few Reasons Circadian Biology Is Crucial For Our Health

1. Improved Sleep Quality: One of the most direct effects of a well-regulated circadian rhythm is better sleep quality. Disruptions to the circadian cycle—whether through shift work, travel across time zones, or excessive screen time before bed—can lead to insomnia and other sleep disorders. Adequate sleep is crucial for physical health, mental clarity, and emotional stability.
2.  Enhanced Mood and Mental Health: Studies have shown that disruptions in circadian rhythm can lead to mood disorders such as depression and anxiety. Regular sleep-wake cycles help stabilize mood and reduce irritability and stress. Exposure to natural light during the day can boost neurotransmitter production, including serotonin, contributing to a sense of well-being.
3.  Weight Management: Meal timing is an important factor in circadian health.  Our bodies are designed to process food at certain times. Eating at night or irregularly can disrupt metabolic processes, potentially leading to weight gain, and other metabolic issues. A consistent eating schedule aligned with your circadian rhythm will help in regulating appetite and maintaining a healthy weight, and better gut health.
4.  Boosted Immune System: Circadian rhythms play a role in the immune response by influencing the timing and function of immune cells. Maintaining a healthy circadian rhythm will help your body fight off illnesses more effectively.  There are many studies showing the positive effects of UV light on illness and disease in the body.
5.  Heart Health: Research shows that individuals with irregular sleep patterns have an increased risk of cardiovascular diseases. A well-timed schedule that promotes regular sleep can contribute to heart health by managing blood pressure and reducing inflammation.

How Can You Work To Maintain Your Circadian Health?

1. Stick to a Sleep Schedule

Try to go to bed and wake up at the same time every day, even on weekends. This consistency helps regulate your body's internal clock.

2. Get Natural Light Exposure

Aim to get sunlight exposure first thing in the morning, before artificial light or screen exposure to help signal your body that it's time to be alert.  This will help with a more  natural rise in cortisol, rather than an abrupt spik which can lead to negative effects on metabolism, mood, hormone balance, etc.   Likewise, minimize exposure to bright screens and artificial light in the evening and use blue light blocking glasses if it can’t be avoided.

3. Open Windows

Open windows everywhere if possible. If you are able to open windows while indoors at work or home or even in your car, you will get the benefits of full spectrum light

4. Create a Wind-Down Routine

Establish a relaxing pre-sleep routine devoid of screens, including activities such as reading, meditating, maybe a warm bath, or even some gentle yoga or stretching.

5. Limit Food Intake Before Bed

Avoid heavy meals and caffeine close to bedtime. You want to finish eating at least 3-4 hours before bed to help with optimal leptin (appetite regulating hormone), and clean up and repair that our cells take care of at night while we are sleeping.

6. Be Mindful When Traveling

If you travel internationally, acclimate by shifting your sleep schedule and meals during travel days to align with the new time zone.

Optimal health cannot be regained or maintained, fully, without taking care of our circadian biology.  The research is undeniable at this point, It is foundational for health and well-being. So, protect yourself from artificial light as much as possible, spend as much time as you can outside and embrace the natural rhythm of light and darkness in nature.