Meet Your Circadian Rhythm
What is the Circadian Rhythm?
We live in a modern world where food and light are readily available all hours of the day and night. However, the daily pattern of light and dark which is the circadian rhythm still governs our behavior and physiology & plays a major role in how productive we are.
We are meant to be awake, active and consuming food during the daylight hours or the active phase of the circadian rhythm, and asleep when it is dark. The body needs this master internal clock to maintain mental clarity, healthy moods, cardiovascular health, stress levels and immunity.
How does it work?
Ok so this part is one with some new terminology but it makes an interesting read. Located in the suprachiasmatic nucleus (SCN) of the brain’s hypothalamus, the master clock receives light signals from the eye’s retina and sends that information to various parts of the brain, including the pineal gland that releases melatonin (the sleep hormone).
These signals vary throughout the day, which is why your circadian rhythm typically coincides with the sun’s cycle. At night, your SCN receives signals that it’s dark and late in the day. This causes it to send a message to the brain that it’s time to release melatonin, which makes you sleepy. The opposite occurs during the daytime because light signals suppress melatonin production.
Every 24 hours, the clock is reset as sunlight comes through. In addition, “clock genes” found in every cell of your body, also influence this rhythm, regulating physiological processes like energy metabolism, immunity, and memory formation.
We mess up our clock by staying up late, working on our computers or smartphones, rarely getting outdoors or exercising, eating processed foods, and going on drinking or food binges in the early morning hours, and then drinking large volumes of caffeine to stay awake!
It’s not surprising then that the drastic change in lifestyle and human social habits in the last 50 years has been linked to the rise in diseases like obesity, diabetes, sleep disorders, depression, and certain types of cancers, autism, and a variety of dementias, disorders that are likely linked to disturbances in the circadian rhythm.
How to Support a Healthy Circadian Rhythm?
We can have a positive influence on our circadian rhythm through some lifestyle changes:
- Avoid heavy meals and caffeine later in the day – What you eat can impact how you sleep. Food and alcohol cause heartburn, caffeine and nicotine are stimulants that can trigger your brain to keep your body active. Aim to give your body 12 to 14 hours without food to reset (this can include the hours you sleep). Eating our final meal of the day 3-4 hours before bedtime supports the circadian influence on digestion, absorption and detoxification. Eating outside of regular mealtimes often results in weight gain particularly when large meals are consumed later in the evening.
- Consistent Sleep Schedules – Sleep allows the body to conserve energy, repair, rebuild and detoxify. Adhering to a regular sleep schedule that is aligned with our natural circadian rhythm supports these much-needed processes. It’s common to want to take a long nap or sleep in on the weekends, but this can make your circadian rhythm worse. During sleep, growth hormone increases to repair tissues while blood pressure, heart rate, body temperature, glucose and insulin decrease. We consolidate memories and dream during REM sleep while we deeply relax during quiet sleep.
- Exposure to Sunlight & Physical Activity –Exposure to sunlight will help reset your internal clock for the day. As morning approaches, cortisol (the stress hormone) rises to its peak within 30 minutes of waking while melatonin continues to decrease upon exposure to light. Spending time in the bright morning sunlight can facilitate this shift. Daylight is considered the active phase in the circadian rhythm. Working in as much physical activity through the day as possible supports sleep, blood sugar control and metabolic and cardiovascular health.
- Manage stress – Higher stress levels offset your stress hormones and your melatonin levels, leading to more dysfunction of your internal clock. Meditating daily, taking mindful walks in nature, exercising regularly, and limiting your intake of triggering news are all things that can helpkeep your stress levels in check.
- Limit nightly screen use – We now know the effects of morning light on your circadian rhythm. The light in the evening works the same way. Household light from both lamps and blue light emitted from laptops, smartphones and tablets, can trick your brain into thinking it’s still daytime, causing it to suppress melatonin production. “Bright light wakes up your brain,” Start dimming lights about two hours before bedtime and resist the urge to scroll through social media in bed.
The takeaway
There is a reason we are advised to eat early in the day, sleep on time, wake early and exercise!! Your circadian rhythm is essentially your body’s internal clock, and it plays a big role in your mood and energy levels. You can keep yours running smoothly by incorporating the above lifestyle changes, one step at a time and seeing the difference.
Did you try any of the above and notice any changes? Share your experiences in the comments below.
