
Empty-Stomach Intelligence - lbr
http://www.nytimes.com/2006/12/10/magazine/10section1C.t-1.html
======
gpcz
This reminds me of a passage from Ben Franklin's "Autobiography" about
vegetarianism, but could be reinterpreted as a statement on the benefits of
being hungry:

"When about 16 years of age I happened to meet with a book, written by one
Tryon, recommending a vegetable diet. I determined to go into it. My brother,
being yet unmarried, did not keep house, but boarded himself and his
apprentices in another family. My refusing to eat flesh occasioned an
inconveniency, and I was frequently chid for my singularity. I made myself
acquainted with Tryon's manner of preparing some of his dishes, such as
boiling potatoes or rice, making hasty pudding, and a few others, and then
proposed to my brother, that if he would give me, weekly, half the money he
paid for my board, I would board myself. He instantly agreed to it, and I
presently found that I could save half what he paid me. This was an additional
fund for buying books. But I had another advantage in it. My brother and the
rest going from the printing-house to their meals, I remained there alone,
and, despatching presently my light repast, which often was no more than a
bisket or a slice of bread, a handful of raisins or a tart from the pastry-
cook's, and a glass of water, had the rest of the time till their return for
study, in which I made the greater progress, from that greater clearness of
head and quicker apprehension which usually attend temperance in eating and
drinking."

Perhaps Steve Jobs's "stay hungry, stay foolish" quote was literal as well.

------
jackschultz
> The finding was startling, but “it makes sense,” Horvath says. “When you are
> hungry, you need to focus your entire system on finding food in the
> environment.”

I never liked these types of rationalization. If the result was opposite, you
can easily say that it would make sense because when full, you can concentrate
fully on the task at hand, rather than on finding food.

~~~
PakG1
No you can't. This is one of the first fallacies taught in Logic 101. If A
then B, does not mean if !A then !B.

~~~
_delirium
His or her point is that the "evidence" at hand can be rationalized either
way. That is because there is no causal evidence about the relationship
between hunger and productivity adduced here.

~~~
PakG1
Thanks for clarifying the point for me instead of simply downvoting. I see
what was meant here now. But I think the point could have been made better by
pointing out the lack of causal evidence, rather than complaining how it could
be rationalized because pretty much anything in the world can be rationalized
if you try hard enough.

~~~
seabee
The point was made best because it presented a counterexample. Merely pointing
out 'ad-hoc fallacy' (or similarly, my pet hate 'citation needed') might make
the author and a few other people feel good about themselves for seeing the
flaws, but it's a lazy response which adds the smallest value greater than
saying "I disagree", and is better suited to a points-scoring exercise rather
than a discussion.

------
fchollet
Even assuming that the human brain somehow "works better" in a state of hunger
(which this study does not prove), I would still do better work in a state of
satiation.

The number one factor for doing good work is to sit down, get in the zone, and
stay concentrated on your work. I find that being hungry is very distracting
--hunger constantly nagging you out of your task with the urge of getting up
and grabbing a snack. So independently of how well hunger makes the brain
work, for me hunger is detrimental to the only thing that matters.

~~~
graeme
You say you " _would_ still do better". Does this mean you've not actually
tested your belief empirically?

I find hunger is one of the least well understood of our bodily functions,
despite it being accessible to every one of us. Few people test it.

From my experience, and from the experience of everyone I've every talked to
who tries intermittent fasting: You won't get hungry, once you adapt. Most of
us adapted in a few days.

I don't eat until 12-1, and I get up around 8. Hunger never bothers me until
lunchtime, and I feel clear headed and productive all morning.

If you HAVE tried this experiment, then apologies. But I find it very
irritating that so many people i. Have very strong opinions on the matter of
fasting ii. Have never experimented to see how they react to fasting

~~~
superuser2
Fasting signals your body to aggressively conserve resources, making less
available to you and optimizing for maximum fat content. Which is why it's not
an effective dieting technique. When you "get used to it" your body has
reduced its energy consumption but also the energy available to you and your
brain.

The mice are doing better at _getting themselves fed_ but I wonder what the
impact of hunger is on higher order functions like programming, relationships,
management, etc...

~~~
Nav_Panel
It takes a very long time for your body to go into "starvation mode."
Intermittent fasting is actually a reasonably effective dieting technique
assuming you don't binge eat afterward to "make up the difference."

Good source: [http://www.leangains.com/2010/10/top-ten-fasting-myths-
debun...](http://www.leangains.com/2010/10/top-ten-fasting-myths-
debunked.html)

> Looking at the numerous studies I've read, the earliest evidence for lowered
> metabolic rate in response to fasting occurred after 60 hours[0] (-8% in
> resting metabolic rate). Other studies show metabolic rate is not impacted
> until 72-96 hours have passed (George Cahill has contributed a lot on this
> topic).

> Seemingly paradoxical, metabolic rate is actually increased in short-term
> fasting. For some concrete numbers, studies have shown an increase of 3.6% -
> 10% after 36-48 hours[1,2].

[0]:
[http://www.ncbi.nlm.nih.gov/pubmed/3661473](http://www.ncbi.nlm.nih.gov/pubmed/3661473)

[1]:
[http://www.ncbi.nlm.nih.gov/pubmed/2405717](http://www.ncbi.nlm.nih.gov/pubmed/2405717)

[2]:
[http://www.ncbi.nlm.nih.gov/pubmed/10837292](http://www.ncbi.nlm.nih.gov/pubmed/10837292)

~~~
superuser2
Parent seems to be talking about long-term permanent strategy, not sub-72-hour
increments. I apologize if that was incorrect.

~~~
graeme
I said I don't eat until 12. A 16 hour fast, typically.

------
crazygringo
I don't know if I'm different, or what -- but I simply _cannot_ concentrate on
an empty stomach. When I find myself just staring at the computer screen,
unable to write code -- it's usually because it's 11am and I didn't eat enough
breakfast, or 11pm and I didn't eat enough dinner. It's not the distraction of
hunger, it's just that my brain isn't getting the energy it needs to think
properly. I _have_ to go snack on something (usually substantial) to get
enough energy going back to my brain -- and then I'm fine.

In fact, I've often been mystified by people trying to lose weight who barely
eat anything all day, yet still manage to get work done effectively,
participate in meetings intelligently, etc. I wish I could, but I swear, when
I'm hungry it's like my IQ is cut in half.

Still, just from talking with friends about it, it seems like I'm the outlier
here.

~~~
Malician
This is somewhat related and quite interesting.

[http://www.nytimes.com/2010/07/20/health/nutrition/20best.ht...](http://www.nytimes.com/2010/07/20/health/nutrition/20best.html?ref=health)

I have a similar issue. From what I can tell using my layman's understanding
of the nutrition involved, fat or protein will give you steady energy
throughout the day, but sugar or refined carbs (like white bread) will just
temporarily spike your blood sugar and lead to much unhappiness a little
later.

Either way, if I don't pay attention to my energy intake, I don't necessarily
get hungry - I just end up slouched in front of the computer accomplishing
nothing without the energy to even get up and move. My thinking falls into
repetitive ruts - I'll attack a problem from the same direction over and over,
neglect any sort of creative solution, or even fail to execute a basic
troubleshooting routine I should know applies.

The article still seems to apply, though: being too full is really terrible
for maximum motivation and really getting things done. It may be best to eat
good, solid meals, but none of them too massive, and not just before you need
to do hard work.

------
kgarten
I wonder why it's so difficult for news reporter and journalists to link to
the actual paper. "According to researchers at Yale Medical School ..." great
start (irony ;) ). Here's the paper link (unfortunately behind a paywall):
[http://www.nature.com/neuro/journal/v15/n8/full/nn.3147.html](http://www.nature.com/neuro/journal/v15/n8/full/nn.3147.html)

Given the paper I find these sentences highly speculative: "... causes mice to
take in information more quickly, and to retain it better — basically, it
makes them smarter. And that’s very likely to be true for humans as well."

To broad and too vague, ... there are too many influences on knowledge
acquisition (information intake)

~~~
gwern
Always check Google Scholar, which in this case (
[http://scholar.google.com/scholar?cluster=866211161589883826...](http://scholar.google.com/scholar?cluster=8662111615898838267&hl=en&as_sdt=0,9)
) turns up two public copies:
[https://www.med.upenn.edu/ngg/user_docs/Dietrichetal2012Natu...](https://www.med.upenn.edu/ngg/user_docs/Dietrichetal2012NatureNeuroscience.pdf)
/
[http://www.researchgate.net/publication/228063201_AgRP_neuro...](http://www.researchgate.net/publication/228063201_AgRP_neurons_regulate_development_of_dopamine_neuronal_plasticity_and_nonfood-
associated_behaviors/file/79e41502949107cec2.pdf)

Not that I'd place any weight on this. Mice responses differ from group to
group, breed to breed, and need not generalize to humans at all (
[http://www.gwern.net/DNB%20FAQ#fn97](http://www.gwern.net/DNB%20FAQ#fn97) ).
In particular, if hunger really did improve general cognitive performance in
humans, it should be trivial to show this! Take two groups of undergrads, keep
them busy for a few hours so they miss lunch, administer IQ test; done.

In fact, it's so trivial that it's been studied in any number of contexts,
particularly dieting:
[http://scholar.google.com/scholar?q=hunger%20cognitive%20per...](http://scholar.google.com/scholar?q=hunger%20cognitive%20performance)
I dunno about you guys, but skimming over the abstracts and titles, I'm not
thinking 'hunger will turn me into a genius'...

------
beagle3
Hunger and appetite are not the same thing, although they are often conflated.
I doubt anyone posting here has actually felt hunger.

That feeling of "I should eat something now" is either appetite, or ritual
(and/or carb addiction). If you are not malnourished, it often takes 20 days
of fasting for hunger to appear (as many as 40), and when it arrives, you'll
realize it is there: It's not a feeling that goes away if you're immersed in a
book, work project or video game. It's a feeling that you'll be willing to
fight for food now, if needs be. (Addiction can also cause that feeling, but
addiction will go away if your mind is taken with other things. They just feel
different in a way that I don't know how to describe).

Despite living in a western society, I have experienced it several times. The
first, involuntarily (was a vegetarian in the army, and despite rules to the
contrary, there was only sufficient amounts of food if you ate meat), and not
fasting - I just wasn't eating enough for over a month, and then it came with
a sudden force.

The other times, I lost my appetite, so I didn't eat until it came back (as I
often do). Usually, appetite comes back within a day or two. A few times, it
took over 10 and over 20 days.

Food consumption, hunger and appetite have no simple linear relationship.
After two days of fasting (voluntary or forced), the appetite disappears. I
know that seems very unlikely to anyone who hasn't tried it, because it seems
like the appetite (or a feeling you call hunger) just keeps getting stronger
when you don't eat - to the point that it would be impossible to sustain if it
continued linearly. But it doesn't - it just goes away after a couple of days,
your body switches to some kind of maintenance mode (characterized by ketosis)
that actually feels good.

------
kvee
How do we reconcile this with hunger causing ego depletion and choice fatigue?
([http://www.nytimes.com/2011/08/21/magazine/do-you-suffer-
fro...](http://www.nytimes.com/2011/08/21/magazine/do-you-suffer-from-
decision-fatigue.html?pagewanted=all))

~~~
Bsharp
Reconciliation: NYT wants to report on something that sounds interesting and
people will talk about.

------
alabut
There's similar findings that a hungry stomach can make you more awake and
even cure jet lag. It goes back to the 80's - Ronald Reagan used the technique
to look fresh when landing across the globe.

[http://blogs.hbr.org/2009/05/a-fast-solution-to-jet-
lag/](http://blogs.hbr.org/2009/05/a-fast-solution-to-jet-lag/)

When I learned about it last year, I figured it might also work as a technique
to pull off all-nighters and tried it out whenever we had a press embargo for
some feature we hadn't even created yet. It seemed to help a lot, especially
for someone like me that usually needs an absurd amount of sleep to function.

------
capex
There is a difference between being actually hungry, and beginning to feel the
need to eat. Other commenters are comparing hungry kids not being able to
focus on learning, which is absolutely true. Its not just the hunger for them,
its about food insecurity. They don't know if they'll get food tomorrow, so
the idea of staying fed is primordial there.

That said, for me, a state of feeling light-headed with the need to eat in the
background works best. Satiation is a never ending pit, you'll need to fill in
15 minutes after you last felt satiated. But if you can ignore that little
sugar-triggered signal, focus becomes both easier and intense.

------
chenster
Since I started working from home, I found that I'm super focus and productive
in the morning after consuming a cup of coffee. My productivity is at its
lowest after lunch, even a light one, feeling my glucose is running low.

I found it helps to take a small break and do 15 min walk and come back to
work re-boost my attention again. Another thing that helps is to maintain a
low in-door temperature definitely adds more O2 to my brain. Maybe that's why
my last workplace is always so cold with AC blasts at its max.

~~~
eru
Have you tried a standing desk or a walk and nap after lunch?

Those things did make a difference for me.

------
DanBC
I'm having trouble calibrating what people mean by "hungry" in this thread.

Obviously they're nowhere near the eating disordered end of "hungry". (Where
people use a lot of cognition on counting calories and working out how to burn
more calories or evade monitoring, to the point that physical movements slow
down, because they're concentrating so hard on other stuff.)

But is this just missing one meal? or missing a day of food?

------
klt0825
This is actually one of the reasons I do what is now called "Intermittent
Fasting". I found in my teens that I was much, much more focused and alert on
an empty stomach. I've always assumed it had to do my insulin response to
meals as low-carb diets had a similar effect but not eating during the day was
just easier.

------
talles
For me, almost everything feels better with an empty stomach. Studying,
working or just having a good time. I do some small water fasts during my
month (1-2 days fasts) and these days are definitely the best ones: I feel
lighter with a clearer mind.

But there is on thing in the article that I think is BS: “When you are hungry,
you need to focus your entire system on finding food in the environment”. I'm
not an expert in this area but I always believed that this benefits were due
the shutdown and cleanse of your digestive system.

------
jules
I see a major flaw in the generalization from hungry mice solve a maze faster
to hungry mice are more intelligent (let alone humans). Supposedly you train
the mice to solve a maze by giving them a food reward. It stands to reason
that the hungry mice are simply more motivated to get the food reward. If you
had given the mice some other kind of reward when they solved the maze (e.g.
sex) then the hungry mice may not solve it faster, but sex deprived mice may.

------
bernatfp
That's exactly what I've been noticing with myself. As time passes from my
last meal, I start becoming more productive, I can read faster, remember many
more things... I feel like my brain weights less. On the other side, just
after having had lunch I need to have a short nap, otherwise it takes me like
1h to be fully operative again.

------
sfrechtling
I also find that I perform best when I fast for the morning, and then have a
rather large lunch. Its a little hard around 11am, but I don't crash as easily
- and I'm able to push through problems easier afterwards.

The only thing I find is that it sometimes impacts on my creativity; I'm not
able to think of alternate solutions.

------
rlwolfcastle
_The stimulation of hunger, the researchers announced in the March issue of
Nature Neuroscience, causes mice to take in information more quickly, and to
retain it better — basically, it makes them smarter. And that’s very likely to
be true for humans as well._

I am a little sceptical of the claim in the last sentence.

------
amjaeger
When the lab rats are in the maze, is the prize for successfully exiting the
maze a piece of cheese or other food? If so I wonder if this test effective.
If I'm hungry I can probably find the fastest route to a store or restaurant,
but I'm not sure about improved calculus skills.

------
lbr
I notice this all the time - focus better hungry. Just did some research and
dug up the article.

~~~
michaelchum
Same here, I feel more focused and have stronger mental acuity when my stomach
is empty

------
jamesrom
Hunger works for me. I'm less likely to procrastinate if I'm hungry. I can
concentrate better. I can more easily tune out everything else.

Music : Ears :: Hunger : Brain, at least when concentrating.

------
robmcm
So should we be giving kids state sponsored school breakfasts or not?

~~~
patatino
Good question. I once saw a documentary about this topic. They pointed out a
lot of the kids went to school without breakfast at home, because their
parents were poor. After implementing a sponsored breakfast at school grades
improved a lot. Unfortunately I don't remember the name of the documentary.

~~~
vidarh
The poverty issue might very well mean that these meals might be beneficial
primarily by counteracting chronic under/malnourishment and that this is a
more important effect than any benefits of short-term fasting / hunger.

But there are other potential effects as well: It is one thing to be hungry if
you are able to decide yourself what to do. Another when dealing with
authority. We can tell when my four year old son is getting hungry before he
notices it himself because he starts getting cranky when we try to interfere
with what he is doing.

Purely guessing based on that anecdote, it might also well be these kids would
perform better at _what they want to do_ when hungry, but that they are more
docile and find it easier to sit still and pay attention to the teacher when
well fed.

For my part, I used to prefer to go to school without breakfast for many
years, but then again I was usually allowed to sit and work on whatever I
wanted most of the time in many classes, as I was usually ahead.

Of course this is all speculation.

~~~
hmsimha
Your speculation definitely resonates with me. I always had a hard time
sitting still and paying attention in class if I was hungry. For whatever
reason, if I've gone a little bit too long without eating enough, I end up
experiencing sharp pains in my stomach that are incredibly distracting, even
though I doubt I ever went long enough without food to truly have an empty
stomach.

------
terranstyler
This study basically says that Ghrelin makes you smarter. It may well be that
this is to counter the effect of lower blood sugar due to hunger.

Being hungry could still make you "dumber".

------
cperciva
So much for the "kids can't learn if they're hungry" argument for subsidized
or free school breakfast and lunch programs...

------
thejosh
I've heard the same thing somewhere, where if you need to go to the toilet
that's the best time to make a decision.

~~~
hackula1
I find that in this situation, my response is always the same: "Just do it..
be right back"

------
md224
(2006)

------
islon
tl;dr: hunger makes mice smarter, likely to be true for humans as well.

------
contextual
_The stimulation of hunger... causes mice to take in information more quickly,
and to retain it better — basically, it makes them smarter. And that’s very
likely to be true for humans as well._

So based on a so-called scientific study of mice, we have this great insight
on how humans think. This study and ergo this article are either wrong, or
mice are so close to humans in the way they behave that it's ethically and
scientifically indefensible to conduct harmful and lethal experiments on them.

In other words, if mice are such a reliable proxy for human beings, we
shouldn't experiment on them because they are people too. If they are not
reliable proxies, then we need to stop using them as such.

That fundamental question is largely being ignored in the scientific
community, but until it's answered, these studies are bad science.

