The Photoperiod Effect, Diabetes, Hypertension

and more, in a nutshell

first published October 2, 2006 - last revised October 2, 2006

by Russell Johnston

Introduction

Photoperiod: the length of time spent exposed to light, whether sun or artificial light.

ipRGCs, “intrinsically photosensitive retinal ganglion cells” (“dots”): the third kind of photosensor present in the human eye; quite distinct from rods or cones. Insensitive to red light, these sense night and day and control the majority of the human hormone system.

If you've been waiting for some good news, here it is: we stand at the edge of a breakthrough in our understanding of chronic illnesses as a whole. The primary cause of the present epidemic of diabetes, Alzheimer's, multiple sclerosis, allergies, asthma, overweight, depression, bipolar illness and much more is just now coming into view. That's a very good thing, because those very illnesses are rising throughout the industrial (and industrializing) world at a spectacular rate – diabetes has doubled in the past thirty years, cancer increasing about 1% per year, and more people in North America now have eczema than don't – eczema has doubled in less than a generation! One could go on for some time listing the rapidly rising rates of chronic fatigue syndrome, cancer, heart disease, multiple sclerosis, obesity, and far more. However my analysis of the scientific research we now have in hand convinces me that there's still better news: it won't be very difficult to reverse the tide. The best news is that we don't have to wait. Each of us, personally, can get ahead of the curve right now and substantially improve our present and long term energy, health, mood and weight (plus more) with some relatively simple lifestyle changes that you probably haven't heard much about yet, but which very recent research is increasingly pointing to. (At very little cost.)

To start with something startling to most of us; did you know that using only a red light (if any) when you go to the bathroom in the middle of the night may be the most important “lifestyle change” that you can possibly make to improve your health, putting your entire hormonal system back on track – a hormone system that affects every other aspect of your health? If you haven't been closely following very recent medical research, that might sounds a bit bizarre – but then again, most new scientific discoveries are surprising and always have been. Surprise is, after all, part of the definition of “discovery”: discoveries are unanticipated knowledge, not just the eventual confirmation of old ideas. A great many medical discoveries have emerged over the last few years, and decades. These discoveries are radically changing our picture of how human bodies work, and what keeps our bodies and minds vigorous and healthy into old age – not to mention, what turns so many of us obese, tired, ill, and prematurely old. We now know enough to piece together a very plausible picture of just how and why chronic illnesses develop, and simple steps we can take to avoid them.

I expect readers to be skeptical of this new picture: by all means check the studies and decide for yourself. Believe me, you won't be more skeptical than I was about my present conclusions than I was, for years – yet this is what the research is increasingly showing. Not stating – but giving strong evidence for.

The answers I will describe here are ones that I half-stumbled over by accident at least twice starting a quarter-century ago when very little supporting research was available – but at that time I rejected them out of hand because it all seemed unthinkable to me. Long periods of darkness being vital to health? Artificial light after sunset being truly harmful, even over a long period? It just didn't seem scientific to me. It was unthinkable. Practical answers to my own chronic health problems should have been obvious to me back then, but the very idea that light, and dark could be seriously affecting my health was simply insane to me then, so I ignored my own experience. Now there's a wealth of scattered evidence from medical research to show just how sane and scientific such ideas are.

Now that the research is in, none of us have to guess: we know that how much light we are exposed to does affect our health. Medical science now fully accepts this, in the case of breast cancer at a minimun. Granted, many of the conclusions I'm stating here go well beyond what researchers have stated, even as hypotheses – but what I allege is very much consistent with the newly-emerging evidence. The same goes for the mechanisms and causal “pathways” that I'll describe here. Tying cause and effect together in such ways may be (so far) unique to this paper: but the evidence I'll cite does support such hypothesizing, and often in surprising concrete detail.

Just as you probably do, I thought the idea that extending my days and interrupting my nights with artificial light could be doing me serious harm was too crazy even to put into words until only a couple of years ago. It wasn't among those things that I even imagined to be possible, under any circumstances. So, like so many others I have pursued many other possible ways of improving my health and escaping chronic conditions: I tried diet, vitamins, and all the rest. Unfortunately, without much result. My medical problems slowly became worse year by by year. Consistent with my own experience, recent research into the benefits of vitamins is quite discouraging, with only a few bright spots. Like so many others, I was looking in the wrong place. Now, a growing body of research is pointing towards another way in which returning to a natural rhythm could markedly improve our health. This is the “Photoperiod Effect”: the effect of prolonged exposure to light each day upon our health. Chronic light exposure is pushing us towards chronic disease. Bright light and exercise during the day are also very important in helping set our biological clocks and rhythms, but it is artificially long, extended days under artificial light, that are most profoundly wearing upon our health, energy, and mood over the years. That is the conclusion that a small universe of data points scattered throughout thousand and hundreds of thousands of studies have convinced me of.

My own sudden recovery from so many of the effects of a very serious, chronic and disabling diagnosed genetic illness proved to me that as in other “genetic illnesses”, environment was at least as important in creating illness as genes. Spurred by that success, I dove into the research headlong to find out just why I had made that recovery, and whether other chronic illnesses (some frequently comorbid with my diagnosis) might also have similar causes. I found more than I could have imagined, so many threads that tied together to form a single picture of why chronic illness is now so problematic in the “First World”, and in newly industrialized nations such as China as well.

As my health improved, I hit the studies. At least glancing at hundreds of thousands of abstracts of medical experiments, surveys, and reviews, and reading tens of thousands of them. By the summer of 2005 a unified picture had began to emerge from the blizzard of data: a conclusion that I still find quite as remarkable as I found it to be a year ago, although our children may wonder why we could ever have thought anything else: artificial light may well be the most important factor harming the health of people in industrialized nations – at the very root of chronic illness after chronic illness. The majority of those illnesses, including diabetes and multiple sclerosis were rare or unknown before the invention of cheap and very bright gas lighting around 1810.

As a great many medical researchers are willing to admit now, albeit in more limited ways: the evidence is that darkness - real, consistent, uninterrupted darkness - is essential to the health of our hormone system and our bodies as a whole. Using artificial light to extend our days has a price over years and decades – a terrible price. However shocking that might seem, this hypothesis fits the growing mass of scientific research on chronic illness and the human hormone system very well. In fact, shockingly well. Now, I can't guarantee that I have every detail of this very large picture exactly right – in fact, I'm quite sure that I must have made at least a few mistakes. At the very least, I may have made errors in trying to piece together the very precise causal pathways, that can explain in true detail, down to the cellular level, just how over-exposure to light is producing each of these effects. As well, a few of the very many studies I'm working from may well turn out to be wrong in time, themselves – scientific studies aren't perfect.

Even so, we now know enough to firmly conclude that light, and especially, the now common use of artificial light to dramatically shorten our night-time period of darkness, has undeniable negative effects on human health. Believe it or not, our present free use of artificial light, including TV, computer games, and more, and our lack of respect for our need for long, consistent, uninterrupted periods of darkness every day, is inevitably leading to chronic illnesses such as diabetes, heart disease, and far more – problems that are growing more prevalent every year as our use of artificial light – computers, TV, mobile phones with bright screens, blue LED electronic displays, bright green LEDs on fire alarms, etc, etc - increases. This Photoperiod Effect, well known to affect plants, birds and many other species, including other mammals affects humans as well - and it is very far from harmless. Nature designed us for a long, dark night that we now almost never experience. Poor health is the ultimate result, and countless millions of unnecessary, and very painful deaths. Some of those terrible deaths have been suffered by my loved ones and close friends – including a mentor of mine who helped me through my own illness, and died a few years ago of diabetes; John King-Farlow. I hope the reader will forgive me if I take a moment to thank him now, since what you're reading now might not have come to exist without the kindness of John, and his wife Elizabeth. Now if someone could just lend me a time machine...