The Science of Circadian Rhythms: How to Sync Your Body’s Clock for Better Health

Join Dr. James Odell for Season 2 of the Science of Self-Healing Podcast! He's the medical and executive director for BRMI, as well as a practicing naturopathic doctor for over 35 years, and he's here to share with you his extensive knowledge of medicine from a different perspective.

The Bioregulatory Medicine Institute

The Science of Self-Healing Podcast

Have you ever wondered why you feel alert in the morning, sluggish at night, or completely off after a late flight? In this episode of The Science of Self-Healing, we explore the fascinating world of your circadian rhythm—the 24-hour internal clock that orchestrates your hormones, metabolism, mood, and even cellular repair.

Discover how light, meal timing, and sleep habits influence your energy and long-term health, and learn how ancient healing traditions like Ayurveda and Traditional Chinese Medicine have honored these rhythms for centuries.

You’ll also hear how modern chronobiology is proving what bioregulatory medicine has always known: when you live in sync with your body’s natural timing, everything works better—from digestion and detoxification to immunity and emotional balance.

We’ll cover:

• The science behind your “master clock” and its influence on hormones like cortisol and melatonin

• How eating and sleeping at the wrong times can disrupt health and mood

• Practical ways to realign your rhythm using light, movement, and herbal allies

• Why “night owls” and “early birds” are both right—if they follow their natural chronotype

By the end, you’ll have a simple blueprint for restoring balance, energy, and resilience—one sunrise and sunset at a time.

Transcript for: The Science of Circadian Rhythms: How to Sync Your Body’s Clock for Better Health

Hello, everyone, and welcome to the Science of Self-Healing podcast. For health and wellness knowledge from a different perspective. Produced by the Bioregulatory Medicine Institute, also known as BRMI. We are your source for unparalleled information about how you can naturally support your body's ability to regulate, adapt, regenerate, and self-heal. I'm your host, Dr. James Odell, the medical and executive director for BRMI, as well as a practicing naturopathic doctor for over 35 years. And remember, this podcast is for informational purposes only and is not intended to be a substitute for the direct care of a qualified health professional who oversees and provides unique and individual care. The information here is to broaden our different perspectives and should not be construed as medical advice or treatment. Let's get started.

Welcome to today’s episode. Let me ask you a question. Have you ever noticed how you feel sharp and awake in the morning, sluggish at night, and completely off after a late evening or a long flight? That isn’t random. That’s your circadian rhythm at work. And today, we’re going to explore what it is, why it matters, and how you can use it to support better health.

What Is the Circadian Rhythm?

So, let’s start at the beginning. The human body runs on an internal 24-hour clock called the circadian rhythm. This rhythm guides countless processes—hormone secretion, digestion, metabolism, sleep cycles, even cellular repair. The word circadian literally means “around a day,” and it reflects how our bodies are tuned to the natural cycle of light and dark.

What Does the Circadian Rhythm Do?

Now, many people think circadian rhythm is just about sleep. But here’s the thing—it goes far beyond that. It shapes brain function, immune defense, metabolism, and mood. Pretty much every part of you runs on rhythm. And when the cycle gets disrupted—whether from artificial light, irregular eating habits, or staying up too late—it can lead to fatigue, insomnia, hormone imbalance, lowered immunity, and long-term health issues.

How Does Bioregulatory Medicine View the Circadian Rhythm?

Moving along, how does bioregulatory medicine view this? Well, balance with natural rhythms has always been seen as essential to healing. In Ayurveda and Traditional Chinese Medicine, the timing of rest, nourishment, and activity was emphasized long before we had modern clocks. And now conventional medicine is catching up, showing that when you live in alignment with your body’s internal timing, you recover faster, restore energy more fully, sharpen your mental clarity, and protect long-term well-being.

What Is the Science Behind Circadian Rhythms?

Alright, now let’s shift into the science. At the center of this timing system is a tiny cluster of neurons in the hypothalamus called the suprachiasmatic nucleus, or SCN. Think of it as the master clock of the body. When light, especially blue light, enters the eyes in the morning, it signals the SCN to flip the body into “day mode.” That sets off a cascade of signals—raising metabolism, waking up the brain, and getting you alert and ready for action.

So, what happens next? Hormones step in. Melatonin, often called the sleep hormone, rises when it gets dark. It helps you wind down, repairs your cells, and even acts as a powerful antioxidant to protect your body overnight. In contrast, cortisol rises in the early morning and peaks shortly after you wake. Cortisol is your “get-up-and-go” hormone. It gives you energy, raises blood sugar so you have fuel ready, and sharpens focus so your brain is switched on.

And here’s another layer. Insulin sensitivity—the body’s ability to handle blood sugar—also follows a rhythm. It’s strongest earlier in the day. That’s why eating late at night can lead to sugar spikes and weight gain. Meanwhile, growth hormone and testosterone—two hormones essential for immune strength, tissue repair, and muscle recovery—are released during the deepest stages of sleep, especially before midnight. So if you’re staying up past midnight, you’re skipping your body’s prime repair window.

The Benefits of a Synced Circadian Rhythm

When all of these rhythms are in sync, the body runs like clockwork. Sleep is restorative, digestion is smooth, hormones are balanced, and energy stays steady. But when the rhythms get disrupted, the whole system slips out of tune.

The Disrupted Circadian Rhythm

So let’s shift gears and talk about disruption. In fact, it’s so common in today’s world that it has a name: chronodisruption. That means your body’s timing system is out of sync. And this kind of disruption is linked to a wide range of modern health problems. Screens at night. Lack of natural daylight during the day. Shift work. Jet lag. Late-night eating. All of these interfere with your circadian system.

The first obvious consequence is insomnia. When melatonin production gets blocked or delayed, it’s hard to fall asleep and even harder to stay asleep. Over time, that leads to poor-quality rest and fatigue. But it doesn’t stop there. Mood takes a hit too. Conditions like depression, anxiety, and seasonal affective disorder are all tied to circadian imbalance, especially when serotonin and melatonin cycles get thrown off.

Now here’s another important area: metabolism. When we eat at irregular times—especially late at night—the body struggles to regulate blood sugar. This can lead to insulin resistance, weight gain, and a higher risk of type 2 diabetes.

And don’t forget the immune system. It runs on a rhythm too. White blood cells, inflammation markers, and immune surveillance—the body’s early warning system—all rise and fall at specific times of day. When the rhythm is disrupted, immune defense becomes erratic. That makes you more vulnerable to infections and inflammatory conditions.

On top of that, hormonal balance takes a hit. Irregular cortisol patterns can look like adrenal fatigue. Suppressed melatonin can disrupt reproductive hormones and thyroid function. And long-term disruption has been linked to hormone-related cancers, like breast and prostate cancer, especially in people who work night shifts.

How to Restore Your Circadian Rhythm

So what can we do about it? Here’s the good news: alignment can be restored. And this is where the science of chronobiology—the study of biological rhythms—comes in. Chronotherapy means aligning lifestyle choices with your natural timing.

Let’s start with one of the simplest and most powerful tools: morning sunlight. Getting natural light within the first hour of waking tells your brain it’s daytime. This resets cortisol, balances mood, and ensures melatonin will rise later that night.

Next, meal timing. Eating most of your calories earlier in the day—at breakfast and lunch—takes advantage of peak insulin sensitivity. Avoiding food after sunset frees your body to focus on detoxification and repair during sleep.

Now, let’s talk about bedtime. Going to bed at a consistent time, ideally before 11 p.m., allows melatonin to rise naturally. It also ensures you enter the deepest stages of sleep, when growth hormone and testosterone peak for repair. To make this easier, keep evenings calm—dim the lights, step away from screens, and avoid caffeine. Herbs can also support this process. Adaptogens like ashwagandha and rhodiola help regulate cortisol and daytime stress. Calming herbs like chamomile, lemon balm, passionflower, and valerian encourage melatonin release and deeper sleep.

Exercise timing matters too. Cardio in the morning or early afternoon pairs with natural cortisol peaks and sharpens focus for the rest of the day. In contrast, gentle stretching or yoga in the evening helps activate the parasympathetic nervous system—the body’s “rest and digest” mode—so you can prepare for sleep.

And finally, fasting practices like intermittent fasting benefit from circadian alignment. Ending meals by early evening allows the body to shift into repair. This supports detoxification and a process called autophagy, which is your body’s natural cellular clean-up and recycling system. And research shows autophagy is strongest when your lifestyle matches your circadian clock.

Circadian Chronotypes

Now here’s something important to keep in mind. Not everyone’s rhythm looks the same. These differences are called chronotypes. Some people are morning types—natural early birds. They do best waking with the sunrise, tackling demanding tasks before noon, and winding down early. Others are evening types—so-called night owls. They feel more energetic later in the day, but even they need to protect melatonin at night by avoiding bright light late in the evening. Most people fall somewhere in between. And here’s the key—bioregulatory practitioners often take chronotype into account when making recommendations, because tailoring lifestyle to your natural tendencies makes it far more sustainable.

Seasonal Rhythms

So far we’ve talked about daily rhythms, but let’s not forget seasonal rhythms. These longer cycles influence sleep, mood, energy, and even digestion. In winter, shorter daylight means melatonin rises earlier. The body naturally craves more sleep, grounding foods, and quieter activity. In contrast, summer brings longer, brighter days that support earlier rising, lighter meals, and more outdoor activity. Honoring these seasonal cues strengthens immunity, stabilizes mood, and balances hormones year-round.

Tips on How to Daily Support Your Circadian Rhythm

So, what does all of this look like in daily practice? Imagine starting your morning with natural light exposure and a nourishing breakfast. You hydrate, maybe add an energizing adaptogen, and then tackle your most demanding work or exercise while focus and cortisol are high. At midday, you eat your largest meal, supporting digestion and long-lasting energy. In the evening, you shift toward lighter foods and calming activities. You dim the lights, avoid screens, and maybe sip a calming tea. And by turning in before 11 p.m., you allow your body to access its deepest, most restorative sleep, when repair and detoxification are strongest.

So here’s the bottom line. Circadian rhythms are not just about sleep. They are your body’s blueprint for healing. When you align your lifestyle with them, you give your body the chance to repair, restore, and thrive.

That’s all for today’s episode. Thank you so much for listening. I hope you’ll join me again in two weeks for another episode of the Science of Self-Healing. Until then, be well.

Thank you for your time today, and remember that this podcast is made possible by the Bioregulatory Medicine Institute, also known as BRMI, a nonprofit, global, non political, non commercial institute to promote the science and art of bioregulatory medicine. We extend our gratitude to each and every one of you for listening today, and if you haven't already, make sure to visit us at brmi.online. A treasure trove of invaluable information awaits you there. Connect with us across various social media platforms as well. Come and become a member of our thriving tribe. If you've enjoyed today's episode, we invite you to show your support by rating us, leaving us a review, or sharing the podcast within your circle. Our podcast and mission flourish through sharing, and your participation means the world to us. Our organization is sustained by donations, each of which is tax deductible and fuels projects like this. Visit our website, brmi.online, to contribute or simply to explore the wealth of uncensored and impartial information we offer. No contribution is too small. In just two weeks, we'll be back delving into another captivating topic. Until then, we thank you once again for listening. May wellness and wisdom be your path. Be well.

Bioregulatory medicine is a total body (and mind) approach to health and healing that aims to help facilitate and restore natural human biological processes. It is a proven, safe, gentle, highly effective, drugless, and side-effect-free medical model designed to naturally support the body to regulate, adapt, regenerate, and self-heal. BRMI is a non-commercial 501(c)(3) foundation and will expand and flourish with your support. Our goal is to make bioregulatory medicine a household term.

This article is for informational purposes only and is not intended to be a substitute for the direct care of a qualified health practitioner who oversees and provides unique and individualized care. The information provided here is to broaden our different perspectives and should not be construed as medical advice, diagnosis, or treatment.