What I'm Reading: Lights Out: Sleep, Sugar, and Survival
I finished reading Lights Out: Sleep, Sugar, and Survival for the second time recently. If you care about health and nutrition, this book is a must-read. It is one of my favorite nutrition books, right up there with Protein Power Lifeplan and The Paleo Diet. The basic premise of the book is that our use of artificial lights has disrupted our connection with the seasonal and circadian light cycles of the earth. Until humans discovered methods of controlling fire, we were reliant on the sun for light, just as all wild animals are. However, the real kick in the pants for us came in the 20th century when artificial light became cheap and widespread. We are now in control of “the sun”.
So why does this matter? The human body, just like the body of all animals, is finely tuned to the amount of sunlight that hits the earth during the day. The basic formula is this:
- Long days = summertime
- Summertime = winter is coming
- Winter = famine
- Famine coming = feast now to store bodyfat
There are alot of hormonal workings going on that drive those things, from insulin to melatonin to seratonin and dopamine, but that’s the gist of it.
When you look outside your window in November, you see darkness, usually by the time you arrive home from work. Fifty-thousand years ago, we would’ve gone to bed soon after the sun went down, even though we had fire to light the darkness. Keeping a fire going would’ve been costly in terms of energy expenditure to find the materials to burn. Now we stay up four, six, even eight hours after the sun has set. While we should be laying down, creating melatonin which cascades into prolactin production, we are wide-awake, staring at the TV or computer screen, keeping ourselves up with bright lights. It all boils down to light toxicity which brings on metabolic disorders, including depression (from improper seratonin/dopamine production), heart disease, cancer, dysbiosis of the gut, and any number of other maladies. And because our bodies judge the “days to be long” (it’s “constant summertime” in the modern world!) from all the light hitting the skin, we crave carbohydrates, which causes insulin resistance so that the incoming calories can be stored as bodyfat. It is a survival mechanism that is no longer needed.
Read this book! Yearly! And go to bed earlier. The authors of the book recommend 9.5 hours per night in a completely dark room. Completely dark means completely dark, not mostly dark. That means cover your windows with blinds, shades, curtains…whatever it takes to keep the outside light outside. And cover up your alarm clocks and blinking LEDs. You may miss your favorite TV show, but you’ll feel better, look better, and have a much easier time eating better.
About Scott
Scott Kustes loves to cook and loves to eat. He started Real Food University to help you get maximum enjoyment out of the meals that you eat. To find out more about how he has rebelled against the fast food culture and counting calories or carbs, join the Real Food Revolution.
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[...] book that I highly recommend is Lights Out: Sleep, Sugar, and Survival. This book details all of the ways that lack of sleep affects your health and the evolution of our [...]
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Hi Scott,
I’m quite a ways into Lights Outs and it is blowing my mind. Might be quite a significant book for me, the way Nourishing Traditions was a few years ago.
I went back to look up when you posted your review (which I think you mentioned on a Protein Power blog comment, but I couldn’t find it). I noticed it was about a bit more than a year ago.
Did you ever look into this subject beyond this book, for instance, other books, the references in the endnotes, more recent studies, etc. I think I remember you posting on kids, sleep, & obesity not too long ago.
So I am wondering, a year later, how much of this book’s content and what parts have made an influence on your life and how you manage your light exposure, sleep, etc? Also, if you made significant changes and stuck with them until the present, how are you managing that with coexistance in a light, bright culture and world?
And what reaction to do you get when you tell this stuff to your friends, family, and co-workers? I liked your description “three heads look” when you say that cholesterol isn’t a disease. i imagine this is similar, if not worthy of a 4 head look
. Cheers.
Hey Anna,
Glad to hear you’re enjoying the book so much. I never checked into the referenced endnotes, but I can explain how the book influenced my health habits. Lights Out was one of the first books that I recall reading when starting this journey. I had read the Zone books prior to that and incorporated the 40/30/30 way of eating into my initial diet foray.
But Lights Out really kick-started my desire to learn anything and everything about the body. That our use of light could so heavily influence how we reacted to the rest of our environment fascinated me. It set me on the path of learning all about evolution and led me to find a Biochemistry textbook. After LO, I picked up Origin of Species and Jared Diamond’s series of The Third Chimpanzee; Guns, Germs, and Steel; and Collapse. Basically LO put me on a path to learn as much as I can about nature, animal life, how we are alike and different from the other animals, evolution, human culture, and how our environment influences our health.
Wow…I’d never really considered it until you asked, but LO was probably the book that catapulted me to where I am today.
So how has it affected me today? I sleep a lot more than I used to and I’m more conscious of how much light is present in my room. Now that it’s winter, I’m sleeping 8.5-9 hours per night and am usually in bed by 9:30. It helps that I’m not into watching TV, so I don’t have the draw of that. I try to keep as little light as possible in my room and when my wife’s away on travel, I bury the alarm clock below the bed so those lights are gone too. I need some thick curtains over my window to block out everything.
I did notice how much of a difference the dark makes when I used to come home from school and sleep in mom’s basement. It was like a cave and I could easily sleep 10+ hours with the deepest sleep ever achieved. I also try to get away from TV or computer at least 30 minutes before bed as the light disrupts sleep patterns and activates the brain. Books make me sleepy though. So blocking out as much light as possible from my room, sleeping at least 8 hours a night (most nights) and aiming for 9 in the fall and winter, and not watching flashy bright lights right before bed are the biggest changes I’ve made.
The reaction I get: My mom believed it outright. She’s not into the biochemistry and such, but she instinctively knew not to put night lights in our rooms as babies and said she thought it made a difference in terms of sleep quality. My friends and coworkers don’t really discuss it as they aren’t interested. Besides, most people have ready excuses of why they can’t go to bed earlier. My wife sorta believes me, but not to the degree that LO describes. I think she knows that it makes a difference though because she admits to sleeping better the darker it is.
I think people are reluctant to believe that anything about our modern world could be detrimental to our health.
Cheers
Scott
[...] Source: Modern Forager – “Our use of artificial lights has disrupted our connection with the seasonal and circadian light cycles of the earth. Until humans discovered methods of controlling fire, we were reliant on the sun for light, just as all wild animals are. However, the real kick in the pants for us came in the 20th century when artificial light became cheap and widespread.” > Read the Full Article Here [...]
Very interesting. I notice that I awaken when it’s light regardless of when I went to bed. So, in the spring and summer I often get up at 5:00. The sun comes up and my eyes pop open. In the winter I sleep until 7 or 7:30. I just need to go to bed earlier. I’m going to get this book for sure!
I am 100 pages or so into Lights Out, and I have to say it is very rough going. I think I am quite sympathetic to the book’s main ideas, but a great deal more distilling and editing should have been done before this hit the shelves. The tone is sensationalist (“Type II diabetes has increased fourfold, and why you’re next” [my italics]) and very scattered. It reads as though the authors are so excited by what they have to say they can can barely spit it out.
The copious endnotes gave me the impression that the book would be carefully reasoned and clear, but it jumps all over the place, mixing science, politics and cultural critique in a confusing jumble. It makes all sorts of assertions about what early life was like, but because the endnotes are not referenced, how does the reader know what assertions have been peer-reviewed and which are the educated guesses of the authors?
There needs to be separation of the science from the politics. For example, explain the science of a high-protein diet, then explain why the food pyramid doesn’t reflect that science. The authors repeatedly conflate the two.
The authors also seem unable to resist the urge to be clever, strewing “witty” asides far too liberally e.g. “The worms would tell you if they had brains.” or “The Bible tells us so.” Sometimes the tone is formal, more often informal, sometimes conspiratorial.
Finally, I must ask: why is there not a single chart in the book? I know a good chart would help me a lot!
I feel like I will need to re-read it to get the most out of it, but the writing is so painful to me, I know I won’t.
Matthew,
I’m glad you brought this up.
I actually enjoyed reading the book, and found it very thought-provoking and a good reminder that I don’t make enough effort to get enough good sleep. But I don’t have an extensive knowledge base in early human lifestyles (only a fairly recent interest which spurred some reading) to compare to some of the authors’ assertions, either. Mostly I wondered, if this is so obvious, then why are Wiley/Formby the first and only ones to “get it”?
I did some further online “digging” later, particularly about T.S. Wiley and her collaborative relationship with the other author, Ben Formby, because I was thinking about reading their next collaborative book, Sex, Lies, & Menopause. Wow, I stumbled into some strange stuff.
Of the two authors, Formby is the one with academic degrees and research credentials and Wiley’s credential appear consist of “what she has learned on her own and from Formby” rather than conventional academic credentials. In the end, I didn’t bother reading SL&M, because I could never really determine if Wiley has any credibility or not. At some points she was claiming academic degrees which it turns out she never earned. That raises a big, big flag with me. “Attended” is not the same as graduating.
Also, it appears these two authors no longer have a collaborative or cooperative relationship (they “broke” over a disagreement on publishing some material about bioidentical hormone therapy in their second book – I think in the appendix) and Formby has distanced himself professionally from Wiley and sort of disappeared, at least in terms of lay publishing. Wiley moved into a entrepreneurial bioidentical hormone protocol arena.
I first learned of various charges and characterizations against T.S. Wiley when I started reading some of reviews of SL&M on Amazon.com. A little more online searching dug up more details and charges about all sorts of things.
For instance, there is a lot of controversy “out there” surrounding Wiley, her husband and their ethics, business practices, and her self-promotion and “credential inflation”. I don’t know how much is true, but my eyebrows were raised.
Wiley also developed an unusual high dose bioidentical hormone protocol and pedaled that program to compounding pharmacies that is apparently quite different even to most BHT practices (which already aren’t mainstream), and that has created a hornet’s nest of issues. There are many, many women claiming to be severely damaged by the unusually high doses in her “Wiley Protocol”, which she claims is based on her “research”. Of course, I don’t really know how credible they are or not, either, but without a lot more investigating, the strange nature of the charges against Wiley, with her documented “credential inflation” created enough doubt in my mind to give me pause before reading more of her work or accepting anything she says without credible, supporting evidence, from “outside” sources.
I was unable to find much more about or from Formby, other than he is associated with a “institute” of some sort in Santa Barbara and he has published a *lot* of research papers. I don’t have the expertise to evaluate his papers or assign merit to them (quantity is not quality, of course). Some of the reviewers of both their books have said that when the references cited in the copious end notes are looked up, they often offer little in support of the authors’ interpretations and assertions. I wish I could have found out more about Formby, but he seems to keep a much lower public profile than his former protegé, Wiley, despite his many published research papers.
So in the end, I had a lot of questions about the authors of these books and how much of what they say is supported by accepted data and how much is not supported well at all. Throughout the book, they bolster their argument that it is all from NIH research, locked away in specialized journals and periodicals, and they put the pieces together to create the puzzle picture, but as my husband reminds me often (whose research in another area is NIH supported), NIH funding doesn’t necessarily guarantee the science is good, either.
I’d be curious to know of any other Modern Forager readers came across any of this contradictory info about the book’s authors, or if anyone even looked that further.
I think many of the 1-star reviews on Amazon really nail it.
I recognize that this is not my blog. But I would be wary about making anything but a very qualified endorsement of Lights Out.
It would be a shame for the excellent advice Scott offers to be tainted by association.
Interesting stuff on Formby and Wiley.
Matthew, I discarded the conspiracy theory stuff in the book. I don’t think it’s aliens that assassinated JFK or whatever they were talking about there. However, I do think the premise, the nuts and bolts, of the book is highly important. Too many people don’t sleep enough…it boils down to that. Whether we need complete darkness or mostly darkness or whatever is of less importance than just sleeping. Considering that most of us are covered while sleeping and that it tends to be pitch black under the covers, I’d say most of us are hitting that anyway. On the surface, the premise makes sense…whether it holds up under tougher examination than I gave it 18 months ago is a different story, but I don’t think anyone will go wrong with getting 8+ hours most every night.
In the end, as with most everything I read, I take what makes logical sense and discard the rest.
For more info on the importance of sleep, check out this tag.
Cheers
Scott
[...] Is It About? Well, it’s about sleep. Whereas Lights Out: Sleep, Sugar, and Survival looked at sleep through the lens of evolution and how it affects our cravings for food, The Promise [...]
[...] and have a nap in the day to make it up. There is a great book Called Light’s Out which the Modern Forager reviewed here….It talks about the effects on our hormones chronic sleep depravation is having and how we [...]
In the book, they talk about the different color spectra of morning and evening. Since most of us can’t go to bed at dusk, would there be any value to wearing lenses to block out the pink and blue spectrum and increase the dusk colors?
Also, what about wearing night goggles? I’d really like something to block out light but let me see to read.
Not sure it’s kosher to answer my own question, but this website by Dr. Phelps, says pretty much the same thing as “Lights Out” and he recommends amber lenses. He uses dark therapy to treat bipolar disorders. Very interesting site.
http://www.psycheducation.org/depression/LightDark.htm
Hey Jan, I’ve heard the blue light in particular is what hurts your sleep, so Dr. Phelps may be onto something. Worth trying for $10
Cheers
Scott
I’m just now reading this book and while I see some interesting possibilities,
what I don’t understand is why it’s all about cold winters with many extra hours of darkness … didn’t humanity spend a lot of time in the tropics during our evolution, in africa? In the tropics, the nights are the same lenght all year round (it’s kind of weird, I lived 2 degrees from the equator for 10 months and the days never changed length, it was hard to track passing months). Sure there are seasons of a sort everywhere, it gets rainier or drier, but every time I read about “the time of coming ice” I just wonder if euro-centricity can be distorting the biological information here.
Lisa: Your skepticism is well founded.
The jist of the book, “we need good quality sleep and enough of it”, is true. The rest is unsubstantiated. Read my earlier comments and that posted by Anna (on June 12th, 2008 1:23 pm) for further clarification on my doubts.
Lisa and Matthew, good calls. The further from reading this book I’ve gotten, the less I believe a lot of what they write. Basically, just get more sleep, in a really dark room, preferably a bit cool.
Cheers
Scott
Scott,
It’s too cool that people are reading that far back on your blog. Gotta love it!
I think a book like this is a good reason to read “around a subject”. In other words, read up on the subject, from more than one vantage point, perhaps even from competing theorists. I think then it is easier to separate wheat from the chaff, to use another one of those annoying grain metaphors. I do agree with Scott’s view, that the main point of getting enough quality sleep and not burning the candle at both ends, is the most important and most well-substantiated point to take from the book.
Lisa, Regarding your comments on living at the equator: People living in the northern latitudes have the greatest incidence of SAD (Seasonal affective disorder) and also the highest depression/suicide rates, probably because of lack of sunlight in the winter. Also, check out http://www.mercola.com for his articles about sun and vitamin D. Light coming through glass loses its beneficial UVB, and the harmful UVA comes through. I think the other side of the coin may be that it’s not so much that artificial light is in itself harmful, but that the lack of enough natural sunshine is causing the problem. However, I have had luck wearing red goggles after the sun sets and a sleep mask at night. I feel much more calmer and relaxed. My carbohydrate carvings have gone away. The only problem is, when I have to be around bright nights at night, now, it gives me a headache!
Just read all your comments, and just recently started this book, (you can see my habits haven’t conformed yet, as I am on the computer at 10pm). It’s a really interesting book, especially the science of it.. As a paramedic, I have some background in anatomy and physiology, (not a doctor) and a lot of what the authors say about the different hormonal reactions in the body make sense. Some I remember specifically and others have jogged my memory, or seem plausible, especially the feedback loops, the body has many of those, positive and negative. I am a bit bummed hearing about the lack of credibility of the authors, but like Scott said, on starting the book, I immediately disregarded some of the conspiratorial talk.. I was slightly annoyed that they even included it, but at the same time, our government isn’t perfect, and the mix of politics and science has proven to dilute or even block the truth in other areas… so who knows.. Americans would have a hard time hearing that their workaholic drive for more stuff was the cause of illness.. Anyway, I will keep reading and enjoying my bed.
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