This month, three scientists were awarded the Nobel Prize in medicine for their work explaining how humans, animals, and even plants adapt their biological rhythm to the cycle of the Earth’s revolutions. It is pretty cool stuff, especially when you realize you have an internal clock that is influenced by the rotation of the earth, the shining of the sun, and many other factors that keep time without your conscious thought. This internal clock, also called the circadian rhythm, enables your body to automatically know when to wake up and get out of bed and when it’s time to go to sleep, eat, and even ovulate. It plays a major role in how productive and focused you are. Like I said: pretty cool stuff. It gets even cooler when you learn that your surrounding environment and how well you take care of yourself can cause this rhythm to go out of balance, which has negative consequences for your health and well-being.
OK, so what's the circadian rhythm?
The circadian rhythm is the biological mechanism that controls the sleep-wake cycle, when hormones are released for ovulation and digestion, and when it is time for your body to sleep so that your muscles can rest, your memories to consolidate, and your immune system to get stronger. Just like the ebb and flow and rhythm of nature, your body also needs this internal clock to operate with the natural rhythm of the earth to maintain good mental clarity and healthy moods, heart function, stress levels, and immunity.
These crucial processes for your health and well-being are largely tied to the shining of the sun, or the natural blue light that comes from the sun’s rays, that is picked up by the suprachiasmatic nucleus (SCN) in your brain. When sunlight comes in through the eyes, the SCN picks up the cue that it's daylight and time to get up and be active. As the light diminishes and then disappears, the clock signals the body that it is time to sleep. Every 24 hours, the clock is reset as sunlight comes through. In addition, genes, or "clock genes" found in every cell of your body, also influence this rhythm, regulating physiological processes like energy metabolism, immunity, and memory formation.
Is our modern lifestyle messing with our biological clock?
In short: absolutely. It's pretty cool that we have a clock that is able to adjust our biological rhythm to our environment, but it's not so cool that our clocks are actually fairly screwed up because we don't abide by nature’s rhythms. 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—just to name a few.
To say that our circadian rhythms have been disrupted is an understatement. Every system of the body needs to be in sync for the system to work well and efficiently. When the circadian rhythm is off, the body goes out of sync. 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 associated with disturbances in the circadian rhythm.
Can we adopt a circadian-rhythm-friendly lifestyle?
Yes! The good news is that the circadian rhythm is susceptible to disturbances, but it can also be brought back on track with these five lifestyle changes:
1. Enhance natural light exposure.
It's important that you expose yourself to natural life (versus the light coming from your computer screen or TV screen), especially in the morning and throughout the day.
- Once evening sets in, start dimming the lights inside your home.
- Make sure your bedroom is completely dark (no TV or LED screens) when you go to sleep.
- If you travel a lot in different time zones, try using this app. It details when to expose yourself to light and when to avoid it to try to reset your clock and avoid jet lag.
2. Get outdoors.
Though it is helpful to use a lamp when necessary, it's also important to expose yourself to natural light throughout the day.
- Spend more time outdoors where you get more exposure to natural light.
- Take two or three days to go camping where you have no access to electronics or even watches, allowing the sun to dictate when to rise and when to go to sleep. Research shows this can greatly affect your sleep-wake cycle.
3. Practice good sleep hygiene.
The more regular your sleep, the better regulated your circadian rhythm will be.
- Make sure your room is only for sleep and sex and is kept dark, quiet, and free of electronics.
- Relax and do other stress-free activities—like journaling or reading—for an hour before sleeping.
- Do not take naps longer than 20 to 30 minutes.
- Limit caffeine use in general, and do not have any caffeine in the evening.
- Keep a consistent schedule for going to sleep and awakening, only varying by one hour every now on then (like on the weekends).
4. Eat at set times.
Harvard scientists have discovered that we have a food-related clock that might supersede the light-based master clock, likely designed evolutionarily to avoid starvation. Wakefulness and sleepiness are associated with the timing of digestion and metabolism, so it makes sense that how and what you eat will affect your internal clock.
- The studies suggest that fasting can help readjust sleep clocks in people with jet lag, so you can try a 16-hour fast by eating an early dinner around 4 p.m. and not eating again until 8 a.m. the following morning. Then, go back to a normal eating regimen, making sure you have 12 hours in between dinner and breakfast the next day.
- Avoid eating heavy foods like dairy and saturated fats from meats and instead reach for vegetables and lean protein sources.
- Eat your heavier meals earlier in the day.
5. Manage stress.
Your "clock genes" and the regulation of all biological systems are intricately connected to the stress response. Higher stress levels offset your stress hormones and your melatonin levels, leading to more dysfunction of your internal clock.
- De-stress with a regulation meditation practice for 10 to 20 minutes each day.
- Take mindful walks in nature, appreciating the beauty and the present moment.
- Eat foods that fuel the body rather than those that create stress and inflammation like sugar, trans-fats, processed foods, etc.
- Lower caffeine intake.
- Avoid doing high-intensity activities and watching stress-filled TV at night.
- Exercise in the morning.
Not feeling optimal? Here, a doctor explains how nature can save your health.