Peter Olszewski offers up his thoughts on Linda Geddes ode to the value of sunlight in our lives.

Just when you thought you were aware of just about all the potentially harmful pollutants, along comes news of light pollution, and new knowledge about the dangers of being deprived of good old natural light via our very own star, the sun.

We underestimate the importance of natural light and we make the seriously flawed assumption that the electric light that lights our homes and offices is just as good as the real thing – sunlight.

That is a simplified version of the message of a startling new book, Chasing the Sun: The New Science of Sunlight and How it Shapes Our Bodies and Minds by science journalist Linda Geddes.

Basically I think we all understand the basics about sunlight in that exposure to it can be both benevolent and malevolent.

But Geddes book concentrates of just how vital sunlight is and her observations are illuminating [ouch, bad pun Peter]. She points out that while we all know that  a  measured dose of sunlight makes us feel good, we  are only just beginning to fully understand  how vital sunlight is, how it can heal or prevent  a myriad  of physical and mental maladies and how deprivation of it  can cause  significant health and well-being problems.

And this comes with a warning about our urban lifestyles where much of our high-rise cities become sun-less shadow lands and our addiction to the new technology, which keeps us indoors looking at computers and hand, held devices for hours on end instead of being outdoors soaking up some sun.

To tell the new story about sunlight knowledge,  Geddes takes us back about 130 years ago, to the work of  Nobel Prize winner Niels Rybirg Finsen who dealt with the direct impact of the sun’s rays  on bacteria and on our skin,  and in doing so he  instigated a cure for lupus vulgaris or skin tuberculosis, a dreadful disfiguring  facial disease caused by flesh eating bacteria – Finsen  found the cure by directing ultraviolet rays on patients’ faces.

Finsen first became interest in the sun because as a student in Copenhagen he lived and worked mostly in a sunless room and suffered from anemia and tiredness.   But he noticed his health improved when he was exposed to sunlight. He began to experiment, established the Medical Light Institute and as Geddes writes, “He ushered in a new era of interest in the health benefits of sunlight, which continues to this day.”

And before Finsen, Florence Nightingale  in 1860 observed that dark rooms were anathema for patients:  “What hurts them most is a dark room”, she wrote, “And that it is not only light but direct sunlight they want.”

AS well as thoroughly documenting the need for humans to be subjected to the right sort of light – sunlight –  author  Geddes, in her compact fact-packed compendium, also documents the  emergence of the wrong sort of light and how it causes havoc with the natural  order of things.

She cites a Cities at Night project, which documents the extent of light pollution and how it’s changing due to the popularity of LED street lights.

“Urban lights scatter photons in unwanted directions, including upwards into space,” she writes.

“This scattered light obscures drivers’ vision and wreaks havoc on wildlife.  Mesmerized by this apparent daylight in the night sky, insects life cycles are disrupted, birds migrations thrown off course and trees cling to their leaves longer in autumn – potentially shortening their lives.” 

Even the reproduction of flowering plants is affected by these artificial suns, by disrupting the behavior of pollinating insects, their daily appointment with flowers that open and close at specific times are missed.

And of course there can be no discussion about sunlight and what happens when the light of day fades into the dark of night: mostly we sleep, or we should sleep and once again, our sleep patterns, naturally triggered by the rise of fall of the sun, are vital to our health.

The tightly written book opens with the science of circadian rhythms, explained in not-too-technical terms, and ends on this note, “We spawned from a revolving planet, itself shaped by starlight. And although we create our own electric star to light the night, our biology remains tethered to a monarch mightier than them all: our sun.”

A good read that’s inducive to a good night’s sleep.