
A Meta-Analysis of Blood Glucose Effects on Human Decision Making (2015) [pdf] - gwern
http://www.gwern.net/docs/2016-orquin.pdf
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nshelly
Fascinating. It shows the importance of having a consistent blood sugar level,
especially when we are around expensive food choices. At the same time, it
seems that we could use fasting (resulting in a low blood glucose level) as a
motivation to work hard if we know that work will get us more food.

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XorNot
Except work doesn't get us more food. I have a dollar on me, I know I can get
a lot of sugar right now with that.

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derefr
I've always wondered how productive I could be if I handed my access to
spending money, plus a list of food I like, over to a trustee, and then told
them to buy me food but only give it to me right as I finish things I care
about. It seems like it would create some pretty strong conditioning effects.

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TeMPOraL
Until you slip up - because e.g. you gave yourself too big a quantum of work
to do before your next reward, or something unexpected popped up that you need
to deal with ASAP. Then you'll find yourself tired, hungry, frustrated and in
a downward spiral - because you'll be quite likely making mistakes sabotaging
your work instead of making progress, thus putting off your eating time
further in the future.

And I'm not talking out of my ass; I screwed myself a few times like that with
the whole "precommitment" idea, including losing quite a bit of money -
instead of helping me focus, this only stressed me out further as I was
desperately thin on funds.

Not saying precommitments are a bad idea, just make sure you can handle
failures mentally before going full-Klingon on them.

~~~
derefr
Note the "food I _like_ " part. I imagine that I could have a pantry full of
Mealsquares or something similar (a nutritionally-complete but not-"tasty"-as-
such food), and pots of black coffee, to keep me going monotonously until I
managed to finish my work. The reward is the rich, fatty, sugary, salty,
umami-y food; not food at all.

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throwaway0209
Haven't read the article yet, saved it. However, my experience is that I am
usually agressive and stupid when hungry.

Looking forward to reading the whole paper.

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robobro
As a type 1 diabetic, I agree with these conclusions, and I'd sum it up this
way: when I have a low blood sugar, I feel anxious and want nothing more than
more sugar inside me. Bouts of hypoglycemia definitely make me more impulsive.
With a low enough blood sugar, time feels as if it slows down: I imagine this
is linked to adrenaline... I can tell I have a high blood sugar (over 150)
before checking when I feel grumpy (and bossy), I'm thirsty, and tend to have
0 appetite whatsoever.

Interestingly -- things that require long periods of concentration tend to
lower my blood glucose (according to my continual glucose monitor) and stress
tends to raise it.

If anyone would like to ask me any questions, I'd be glad to answer. :)

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petegrif
The paper makes no mention of subjects in ketosis. Would have been
interesting.

~~~
hoodwink
Agreed. The brains of keto-adapted individuals can use ketones as a source of
energy which are much more stable, although for a long time it was believed
that brain relied on glucose.

~~~
digi_owl
My layman understanding is that glucose is the first choice. But stay off it
for a day or two and the body starts turing fat into ketones as an
alternative.

~~~
hoodwink
Yes that accords with my layman understanding as well. The body will go down
the "path of least resistance" for energy and glucose is easier to metabolize
than ketones. Deprived of glucones, the body will switch over and hum along
once adapted.

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mnkc
If you're interested in the methods and related questions, check out this (4
part) youtube talk:
[https://www.youtube.com/watch?v=xG79jpAYxmQ&index=7&list=PL5...](https://www.youtube.com/watch?v=xG79jpAYxmQ&index=7&list=PL53QUs1SimPO4ErDLB5Hd-s9XCPCkD1E9)

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Houshalter
So is this a contradiction of this?
[https://news.ycombinator.com/item?id=8695417](https://news.ycombinator.com/item?id=8695417)

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Swizec
Judging from the abstract the tl;dr version is: "If you're hungry, you think
about food".

Certainly aligns with my experience.

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dietrichepp
That's not what the article is about. It's about several competing theories
for how blood glucose affects decision making, their predictions, etc. It's
not about hunger per se (blood glucose and satiety are biologically different
enough you wouldn't want to confuse the two).

