
“Why We Sleep” Is Riddled with Scientific and Factual Errors - AuthorizedCust
https://guzey.com/books/why-we-sleep/#no-two-thirds-of-adults-in-developed-nations-do-not-fail-to-obtain-the-recommended-amount-of-sleep
======
raz32dust
Previous discussion:
[https://news.ycombinator.com/item?id=21546850](https://news.ycombinator.com/item?id=21546850)

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AuthorizedCust
While true, it appears to have been extensively edited and added to since
then.

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Fnoord
Do you have a changelog?

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AuthorizedCust
Only informal. The author mentions extensive time spent on this since original
publication, mentions questions he's responded to or sought more advice on
since publication, and I noticed that that last-updated date, near the top,
changes from 2-25 to 2-26. It seems to be actively maintained. While I
understand HN's preference for no duplicate posts, this seems to have evolved
significantly since original posting.

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knzhou
I've seen this posted all over the internet to great acclaim, and honestly, it
just feels feverish and desperate to me, grasping at tiny points as if they
refute the central thesis.

For example, the point that you linked to says that the official
recommendations on sleep are "7 to 9 hours", which Walker simplified to "an
average of 8 hours". I don't see how this simplification is so bad. The point
is that these numbers are all much higher than the 5-6 hours many people claim
to subsist on. It doesn't even change the numbers that much: slightly more
than half of people sleep less than 8 hours, and slightly less than half of
people sleep less than 7 hours. This nitpick does not refute the central point
that having 5-6 hours of sleep generally impairs you, it only takes aim at
phrasing.

I find point #2 (of 5) in this article especially laughable. Here it's claimed
that sleep deprivation is actually a good thing, because it can be used as a
temporary treatment for severe depression. Under this logic, bulimia is a
healthy habit because you should induce vomiting after being poisoned.

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AuthorizedCust
Also, I didn't read his point 2 as saying sleep deprivation is good. I see it
as refuting the idea that not having "enough" sleep absolutely bad.

~~~
knzhou
Respectfully, who cares? In biology, nothing is an absolute. All good things
have bad sides and all bad things have good sides, and that shouldn't stop us
from identifying things that are generally good. Nobody giving general advice
can or should be expected to cover every edge case.

~~~
sleepthrowaway6
Disrespectfully, for someone that harps on about the main thesis, you fail to
ascertain the blog author's main point:

Matt Walker is lacking integrity. Despite his Ivy League status, despite his
PhD and numerous accomplishments, and despite all his prestige and educational
attainment, he's still a high-quality conman.

That's the point. He twisted facts to sell a book and abused his position of
authority to mislead others for money.

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fossuser
I got a strong motivated reasoning/bullshit vibe from Walker in this
interview: [https://www.npr.org/2018/07/20/630792401/sleep-scientist-
war...](https://www.npr.org/2018/07/20/630792401/sleep-scientist-warns-
against-walking-through-life-in-an-underslept-state)

Particularly this section:

> “Sleep is not like the bank. So you can't accumulate debt and then try and
> pay it off at a later point in time. And the reason is this - we know that
> if I were to deprive you of sleep for an entire night - take away eight
> hours - and then in the subsequent nights, I give you all of the sleep that
> you want - however much you wish to consume - you never get back all that
> you lost. You will sleep longer, but you will never achieve that full eight-
> hour repayment as it were. So the brain has no capacity to get back that
> lost sleep...”

I don’t think this follows - seems likely to me that sleep is not some linear
time thing and that there’s a standard overhead that doesn’t need to be
repeated to extend and make up the time. This feels like a symptom of not
understanding the mechanism and making a bad assumption.

I also found the “I won’t mention the cognitive failures I can detect”
irritating. If there’s some actual thing to mention, say it - this kind of
thing sets off alarms for me.

It doesn’t surprise me that the rest is similarly bad, I’m glad someone dug
into it.

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aSplash0fDerp
Not to choose a side, but sleep deprivation can be related to running an
engine with low oil or running it while overheating. Extreme exhaustion is
usually a chemically imbalanced period.

If we see 6 hour workdays become the norm during the automation boom, we may
see that shifting to 12 hour business days with a well rested workforce was
the only way to keep up with the next wave of innovation while keeping 1st
world working conditions.

Would you invest an extra 2 hours a day to your sleep?

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btrettel
While I can't speak to the accuracy of the book criticized, science in general
is riddled with similar problems. Follow the citation trail and you'll often
find that a cited article doesn't say what was claimed or says something
similar but not quite the same. Alternatively, you might see that the cited
article does say what is claimed, but the evidence is weak.

When researchers talk about all of the "low hanging fruit" being taken, it
seems to me that they're blind to all the nonsense that appears once you start
following the citation trail. Maybe every topic has been _touched_ , but even
something that seems definitive in a review article could have major flaws
when examined more closely.

I'm almost done a PhD in engineering, and this has been my experience at
least. I try to "debunk" something in roughly half my publications now.

Edit: I don't mean to suggest that identifying many of these problems is
_easy_ , just that it's not done frequently enough. For example, if you're
doing research in a particular field, you're probably basing it partly on
previous review articles. Take a look at some primary sources in addition to
that. This applies extra if you're _writing_ a review article. Don't just
mirror what some previous review articles say and cite some newer papers. Find
some old but good papers that were missed by previous reviews. Check primary
sources. Etc. This is the job of a someone writing a review in my view.

~~~
sleepthrowaway6
It's also quite jarring to come across a paper on a niche topic (e.g a
specific hormone's effects on certain biological processes), that completely
botches simple, fundamental and accepted facts in your field; facts that the
main thesis relies on.

It's absolutely silly and I find myself finding little of use in the author's
conclusions, or their observations. After spending way too much time parsing
through endless research papers, the only things I pay attention anymore are
methodology and data.

This tells me: is the data relevant to my work? And was the data collected
"properly" (I swear, half the time the researchers half-ass methodology that
the results are fairly worthless)

~~~
btrettel
> the only things I pay attention anymore are methodology and data.

> This tells me: is the data relevant to my work? And was the data collected
> "properly" (I swear, half the time the researchers half-ass methodology that
> the results are fairly worthless)

I've come to the same conclusion, and I'm a theorist myself. Theory is hit or
miss, mostly miss. I still read it just to find the nugget of truth if there
is one. If the data is relevant and was collected properly then it can be a
goldmine, regardless of the theoretical explanation given by the researchers.
But often the researchers measure the wrong thing, or measure the right thing
in the wrong conditions or with some other problem. (One major problem I've
found is that the uncertainties on many measurements in my field are enormous,
but don't need to be, and very few seems to have noticed or cared.)

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pastor_williams
The author of "Why We Sleep" has written a blog post responding to the OP
article and other questions from readers:

[https://sleepdiplomat.wordpress.com/2019/12/19/why-we-
sleep-...](https://sleepdiplomat.wordpress.com/2019/12/19/why-we-sleep-
responses-to-questions-from-readers/)

~~~
Ono-Sendai
Random quote from the above: "The book’s misattribution of the CDC statement
to the WHO will be corrected in the next edition. "

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guzey
Walker said this in [1] and I believe that this position is indefensible

At the time at the time of the book’s publication in 2017 (and today), CDC had
no documents and no pages on its site that would declare a sleep loss
epidemic.

As I noted in section Possible origin of the “sleeplessness epidemic” thing
[2],

>Between late 2010/early 2011 and August/September 2015 [3-6], CDC had a page
on its site titled “Insufficient Sleep Is a Public Health Epidemic”. More than
2 years before Why We Sleep was published, the page changed the word
“epidemic” to “problem”, so that its title became “Insufficient Sleep Is a
Public Health Problem”. … the fact that CDC itself changed the wording from
“epidemic” to “problem” more than 2 years prior to the book’s publication,
indicat[es] that they no longer believed in the presence of an “insufficient
sleep epidemic”

 __Issuing a correction that would just change “WHO” to “CDC” in the next
edition of the book – as Walker suggested – is deceptive. __The CDC long ago
(more than 4 years ago) removed the word “epidemic” from the article, and then
removed the article itself.

If Walker believes that that is sufficient to state that CDC has declared a
sleep loss epidemic, he might as well say that CDC has declared an epidemic of
inhalation anthrax (and forget to note that it was declared in 1958 [3])

Also, Walker never explains why the source for this sleep loss epidemic claim
in the book is a random National Geographic documentary.

[1]
[https://www.bbc.co.uk/programmes/w3csz3s6](https://www.bbc.co.uk/programmes/w3csz3s6)

[2] [https://guzey.com/books/why-we-sleep/#possible-origin-of-
the...](https://guzey.com/books/why-we-sleep/#possible-origin-of-the-
sleeplessness-epidemic-thing))

[3] [https://perma.cc/72CZ-L9DG](https://perma.cc/72CZ-L9DG)

[4] [[https://perma.cc/23UM-849W](https://perma.cc/23UM-849W)

[5] [[https://perma.cc/2E68-ZRL9](https://perma.cc/2E68-ZRL9)

[6] [[https://perma.cc/UJ4W-JHNY](https://perma.cc/UJ4W-JHNY)

[7]
[https://www.cdc.gov/museum/timeline/1940-1970.html](https://www.cdc.gov/museum/timeline/1940-1970.html)

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kneel
>I have many stories of people who slept well on less than eight hours of
sleep, read Walker’s book, tried to get more sleep and this led to more time
awake, frustration, worry, sleep-related anxiety, and insomnia.

This is me. I get at most 7 hours, usually 6. I only feel impaired if I drop
down to 4.

Reading about Matthew Walker's research years ago caused much anxiety and a
loss of sleep, how ironic.

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fireattack
Some of the points feel a little bit pedantic (or even semantic?).

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xmprt
Not sure why this links to section 5 but the entire page is worth reading. It
a little ironic to say that this article changed my perspective on sleeping
(considering this article is showing how you shouldn't believe the first thing
you read) but given how little research I had done prior, I think I at least
know now that there's a lot more that I don't know.

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AuthorizedCust
I accidentally kept an anchor in the URL. My apologies!

