I awoke with the sun on Monday morning, refreshed and aligned with the world. I was exultant to learn that three Americans had won the 2017 The Nobel Prize in Physiology or Medicine 2017 . Jeffrey C. Hall, Michael Rosbash, and Michael W. Young won the prize for “for their discoveries of molecular mechanisms controlling the circadian rhythm,” a topic that has fascinated me for years for how overlooked but critically important it is. The researchers' discoveries, grounded in their work with fruit flies, reveal a massively interesting coordination of the poetically named TIMELESS, PER, and DOUBLETIME proteins that synchronize the rhythms of cells to the Earth and Sun.
Ok, great. But what are circadian rhythms? Most of the time The National Sleep Foundation ’s lay definition will suffice: circadian rhythms are “basically a 24-hour internal clock that is running in the background of your brain and cycles between sleepiness and alertness at regular intervals…known as your sleep/wake cycle.” But we can take some interesting insights from a geekier Wiki definition that “a circadian rhythm is any biological process that displays an endogenous , entrainable oscillation of about 24 hours.”
For those who haven’t spent years working on esoteric test vocabulary, let’s breakdown these italicized terms a bit. Endongenous means “built-in” or “self-sustaining.” A person or plant that is active regularly (yes, even plants are active!) during daylight hours and inactive at night should normally and naturally continue that pattern unless disrupted. If things are operating as they should, healthy livings organisms on planet Earth should follow a consistent pattern or rest and wakefulness on a 24-hour cycle. The Nobel-winning research proved that circadian rhythms are controlled by clocks down to the level of individual cells, controlling critical metabolic functions, influencing sleep, behavior, body temperature, appetite and hormone levels. It’s a pretty deal: our cells have adapted a finely-tuned system to keep us safe and happy and operating at our best. And the system purrs along, diligently serving as an organic, unconscious personal assistant.
Until it doesn’t.
This is where entrainable comes in, which effectively means “trainable.” So, while our circadian rhythms have a kind of automatic inertia to them, they can be taught. Which mean they can change – for good or bad. Perhaps counter-intuitively, what can be trained can be disrupted. In the short term, we all know from our experience what happens when our circadian rhythms are fiddled about with. Think jet lag. Alertness, mood, ability to sleep well, susceptibility to colds and other infections , proneness to error, and appetite are all affected. In the long term, chronic sleep deprivation can increase the likelihood of diseases of inflammation such as heart disease and diabetes.
So our circadian rhythms can’t completely protect us from ourselves, but there is hope. Even in our sleep-disrupted digital chaos, we can take a few steps to help re-educate these entrainable rhythms. The Sleep Foundation offers sensible tips on good sleep hygiene that I’ll expand on in my next blog post. Our bodies want to help us regulate our sleep and energy cycles, if we’re able to stay out of their way.
So, hats off to Jeffrey C. Hall, Michael Rosbash, and Michael W. Young for their achievement proving that for the entire natural world, health relies on healthy sleep cycles.