Your body has a built-in clock that governs your sleep, wakefulness, motivation, and overall well-being. This internal timekeeper, known as the circadian rhythm, is a natural 24-hour cycle that influences everything from energy levels to hormone balance and immune function.
In this blog, we’ll explore what the circadian rhythm is, how it works, and how you can optimize it for better health.
What is Circadian Rhythm?
Think of your circadian rhythm as your body’s 24-hour internal clock that regulates sleep, wakefulness, motivation, appetite, and many other processes.
It keeps you in sync with the day-and-night cycle. It is primarily influenced by light and darkness, which signal when you should feel awake or sleepy.
According to Stat Pearls:
“This biological circadian system has evolved to help humans adapt to changes in our environment and anticipate changes in radiation, temperature, and food availability. Without this endogenous circadian clock, Homo sapiens would not be able to optimize energy expenditure and the internal physiology of the body.”
How Does Circadian Rhythm Work?
A small but powerful part of your brain called the suprachiasmatic nucleus (SCN), located in the hypothalamus, acts as the body’s master clock. The SCN receives signals from light exposure through your eyes, helping regulate your sleep-wake cycle and other bodily processes.
- Morning Light Exposure: Triggers the brain to increase alertness and suppress sleep hormones.
- Evening Darkness: Signals the brain to produce melatonin, the hormone responsible for making you feel tired and preparing the body for sleep.
Why Does Your Internal Clock Matter?
A well-regulated circadian rhythm promotes:
- Better sleep quality
- Improved energy levels
- Balanced hormones (for mood, digestion, and stress management)
- Stronger immune function
- Efficient metabolism (reducing the risk of obesity and metabolic disorders)
- Faster recovery from exercise and stress
What Are The Risks of Circadian Rhythm Disruptions?
When your body clock is out of sync, it can increase the risk of various health issues:
- Weight gain and obesity – A study in JAMA Internal Medicine found that sleeping with artificial light exposure increased obesity risk by 33%.
- Heart disease and diabetes – Shift workers and those with irregular sleep patterns are more likely to develop cardiometabolic disorders.
- Increased cancer risk – A Biochemistry study found that circadian disruption affects DNA repair and may predispose individuals to cancer.
What Are Hormones That Influence Circadian Rhythm?
Your circadian rhythm affects the rise and fall of critical hormones. Hormones such as:
- Melatonin – Released at night to promote sleep.
- Cortisol – Peaks in the morning to help with wakefulness and alertness.
- Serotonin – Boosted by morning sunlight; later converted into melatonin.
- Insulin – Regulates blood sugar based on eating patterns and time of day.
- Growth Hormone – Released during deep sleep for cellular repair and regeneration.
Why Do Many People Have an Unhealthy Circadian Rhythm?
Modern life often disrupts our natural rhythms due to several things including:
- Artificial light overexposure (blue light from screens delays melatonin production)
- Inconsistent sleep schedules (work stress and late-night scrolling interfere with natural sleep patterns)
- Lack of natural sunlight (indoor lifestyles confuse the body’s internal clock)
- Poor diet and sedentary lifestyle (processed foods and lack of movement disrupt metabolic function)
What Does The Bible Say About Routines & Rhythms?
God created the world to operate in cycles of work and rest. Ignoring these rhythms often leads to burnout and disconnection from purpose.
Aligning with God’s design for rest and work can improve not only physical health but emotional and spiritual well-being.
- Genesis 1:14: “Let there be lights… to mark seasons, days, and years.”
- Biblical rhythms included daily prayer at set times, Sabbath rest, and morning gratitude (Lamentations 3:22-23: “His mercies are new every morning.”).
- Ecclesiastes 3:1-8 – “To every thing there is a season, and a time to every purpose under the heaven: A time to be born, and a time to die; a time to plant, and a time to pluck up that which is planted; A time to kill, and a time to heal; a time to break down, and a time to build up…”
How to Optimize Your Circadian Rhythm?
In TCM, qi (life energy) flows through the body in a 24-hour cycle, known as the organ clock.
Each organ has a specific 2-hour window during which its qi is strongest, allowing it to best perform its functions.
When this natural flow of energy is disrupted—by irregular sleep, stress, or poor lifestyle habits—it creates imbalances that affect physical, emotional, and spiritual health.
Morning Routine (5 a.m. – 11 a.m.)
- Sunlight Exposure: 10–20 minutes of natural light in the morning.
- Hydration: Start your day with warm water or herbal tea.
- Focused Work & Creativity: Engage in deep work between 9 a.m.–12 p.m.
- Morning Exercise: Helps regulate metabolism and energy levels.
- Protein-Rich Breakfast: Eggs, Greek yogurt, or a smoothie with protein and healthy fats.
Afternoon Routine (11 a.m. – 3 p.m.)
- Balanced Lunch: Prioritize protein and fiber for sustained energy.
- Midday Movement: A 10-minute walk outdoors enhances focus.
- Limit Caffeine After 2 p.m.: Prevents sleep disturbances at night.
Evening Routine (5 p.m. – 9 p.m.)
- Early Dinner: Finish eating at least 3 hours before bedtime.
- Dim Lights: Use warm lighting or candles to encourage melatonin production.
- Family Connection Time: Engage in meaningful conversations and reflection.
- Blue Light Protection: Avoid screens or use blue-light-blocking glasses.
- Relaxation Rituals: Try gentle stretching, mindfulness, or herbal teas.
Night Routine (9 p.m. – 11 p.m.)
- Sleep Preparation: Keep your bedroom cool (60–67°F) and dark.
- Gratitude Journaling & Prayer: Helps with emotional balance.
- Consistent Sleep Schedule: Aim for 7–9 hours of sleep nightly.
How Does Traditional Chinese Medicine (TCM) View Circadian Rhythm?
TCM recognizes the body’s 24-hour organ clock, where different organs are most active at specific times:
- 1–3 a.m. (Liver): Detoxification and emotional processing.
- 3–5 a.m. (Lungs): Oxygen replenishment and grief processing.
- 5–7 a.m. (Large Intestine): Ideal time for bowel movements.
- 7–9 a.m. (Stomach): Best time for digestion and a nourishing breakfast.
Practical TCM Tips for Circadian Health:
- Sleep by 10 p.m. to support organ repair cycles.
- Morning Hydration: Drink warm water or ginger tea upon waking.
- Eat According to the Clock: Have the largest meal midday when digestion is strongest.
What is The Role of Light in Circadian Rhythm?
Morning light and evening dimness are key to regulating cortisol and melatonin for balanced sleep-wake cycles.
- Morning Light (Sunrise to 10 a.m.): Signals cortisol release for wakefulness.
- Midday Light (10 a.m. – 2 p.m.): Stimulates vitamin D production.
- Evening Light (Sunset to Night): Triggers melatonin production for sleep.
- Blue Light Exposure Before Bed: Delays melatonin and disrupts sleep cycles.
What Are Supplements to Support Circadian Health?
If you struggle with falling or staying asleep, certain supplements can help regulate your circadian rhythm and promote restful sleep.
Here are some key options to support your body’s natural sleep-wake cycle.
- Magnesium (200–400 mg): Supports relaxation and deep sleep.
- Melatonin (0.5–1 mg): Helps reset disrupted sleep schedules.
- L-theanine: Promotes calm and focus, reduces stress.
- Ashwagandha: Balances cortisol levels for better sleep.
- Glycine (3g): Improves deep sleep by lowering body temperature.
- 5-HTP: Boosts serotonin, supporting melatonin production.
- Passionflower Extract: Relaxes brain, reduces anxiety, and improves sleep.
- Valerian Root: Natural sleep aid, supports relaxation and reduces time to fall asleep.
Aligning your daily routines with your body’s natural clock is one of the most powerful ways to enhance sleep, energy, and overall health. By making small but intentional changes—like morning sunlight exposure, consistent sleep schedules, and mindful evening habits—you can restore balance to your circadian rhythm and experience profound health benefits.
Where Can You Watch The Dr Josh Axe Show on Circadian Rhythm?
Your body thrives on rhythm. Give it the support it needs, and you’ll feel the difference in your sleep, mood, metabolism, and longevity. Watch the full episode here!
