What You Don’t See That Impacts Sleep Health & Wellbeing
Most of us under-appreciate darkness.
Darkness tends to make us nervous.
Perhaps as a result, our world is being polluted by something we all take for granted and would never think of as pollution.
Light.
Light is polluting the night.
As a visual species, humans feel safer and more at ease in lit-up places. So we light up the night, thinking this is of benefit to all. Countrysides within miles of cities are brightened too, especially on cloudy nights when light is reflected back down on earth.
What we don't realize is that all this light negatively impacts human health, wildlife, and our ability to experience a source of awe and wonder.
Affecting human health
Humans need darkness at night. In response to darkness our bodies produce melatonin, the master hormone that signals all the essential functions the body performs at night.
Melatonin is essential for sleep. The ideal sleep environment is dark like a cave. Even little points of light from ubiquitous LEDs on TVs, computers and GIF electric sockets disturb the production of melatonin, disrupting and undermining sleep.
Melatonin does even more for us than help us sleep. It is associated with hundreds of bodily processes. Further, it is a powerful antioxidant, reducing inflammation, the source of disease.
Low melatonin is associated with breast and prostate cancer, thyroid problems, colitis, and the acceleration of biological aging.
Impact on wildlife
Wildlife depends on darkness.
Many animals are nocturnal, sleeping during the day and active at night. Light pollution destroys their ability to function. Prey species hide in darkness while some predators depend on it. Frogs and other amphibians require darkness for their breeding rituals.
Birds migrate by the stars and can be led off-course by city lights. Many birds end up colliding with lit-up buildings in disorientation. Further, artificial cues from the night can cause birds to mistime their migrations.
Plants also depend on night darkness to regulate circadian rhythms. Some plants depend on nocturnal pollinators.
A lit-up night is disrupting whole webs of ecological interrelationships.
Blinding us to awe
The night sky inspires a timeless sense of awe. A sky full of stars reminds us how vast the universe is and provides perspective on our place in the grand scheme of things. It connects us to a sense of mystery and how our ancestors may have experienced the world.
I, personally have always been fascinated by the mystery of darkness. Though wary of it like anyone else, I am drawn to the familiar made unfamiliar in darkness.
I will make opportunities to be outside away from the city at night. Be it cross-country skiing under a full moon or kayaking under the stars, there is something utterly magical about the world at night.
I remember once meeting a man in New York City who had never seen the stars. He had never left the city. He lived in an entirely human-made world. His impoverishment saddened me and I knew there were millions of others like him, missing the existential wonder of seeing infinity stretched out before you.
Health, wildlife, awe.
Not to be traded away.
Darkness is necessary - despite our attraction to light.