Circadian Rhythm is commonly referred to as your sleep/wake cycle, and this cycle has huge implications for human health and longevity. Ideally your daily cycle should be in sync with the earth with wake cycles controlled by exposure to high levels of “blue light” early in the day and lack of exposure to Blue or Green light during the evening.
Many aspects of our modern lifestyle can wreak havoc on our ideal circadian rhythm with potentially deadly consequences if continued over the long haul. Three of the biggest disrupters of a healthy circadian rhythm include:
Overexposure to blue and green light spectrum in the evening and night
Underexposure to Blue and Green light early in the day
Out of sync feeding cycles with a lot of eating occurring in the evening and night
Blue and greenlight are part of the spectrum of light given off by the sun, digital screens (including phones, tablets, TV’s and computers, electronic devices and fluorescent and LED lighting. Early exposure to sunlight is the ideal source with an early walk outside.
In the normal course of human evolution prior to the advent of electricity humans got no blue/green light exposure at night and this is important because Blue and/or Green light signals “wake-up” to the pineal gland in the brain and shut off melatonin production. This is a very big deal because melatonin does a whole lot more than make you sleepy including supporting the healthy functioning of all our cells and specifically the energy powerhouse of your cells the mitochondria.
Out of sync prolonged eating – another key element of our evolutionary heritage is that humans rarely ate anything at night. There was no light so people tended to eat during the day and go to sleep relatively early. In addition, modern life includes way too long a daily window of eating with most Americans eating during a 15-hour window with almost constant food/calorie intake.
This prolonged eating window coupled with late night eating is also out of sync with our genetic heritage. Constant food supply and nighttime lights are a very new phenomenon for humans beings. This is only something that has only been part of our existence for the past 50 – 100 years. For hundreds of thousands of years prior to this no one ever ate at night, and people consumed all their calories during a much shorter time window during the day. In addition, people were forced to fast on a frequent basis.
Camping to the Rescue! – Believe or not something as simple as going camping for one week has been proven to rapidly fix all of these issues! A 2013 Study in “Current Biology” showed that people’s circadian rhythm will synchronize to a natural, midsummer light-dark cycle if given the right stimulus (camping)/ For the first week of the study participants went through their normal routines of work, school, social activities and their normal sleep schedules.
For the second week participants camped in tents outdoors with only natural light and campfires (no blue or green light!). No digital devices were allowed. The response was pretty amazing: they shifted their wake up time approximately 2 hours earlier and melatonin release and shut-off was optimized with light/dark cycles of the earth. This was true even for self-proclaimed “night owls”.
Needless to people almost always adjust their food intake timing while camping as well with the strong tendency to not eat during darkness.