
Salt, We Misjudged You - gruseom
http://nytimes.com/2012/06/03/opinion/sunday/we-only-think-we-know-the-truth-about-salt.html
======
arn
So, I always cringe a little when I read medical conclusions in the mainstream
media. And I'll be upfront. I'm probably biased on the side of medicine on
this one. I'm a former nephrologist.

The one study this person mentions by name (and dismisses) is the DASH-Sodium
Study.

<http://en.wikipedia.org/wiki/DASH_diet#Study_Results>

"Like the previous study, it was based on a large sample (412 participants)
and was a multi-center, randomized, outpatient feeding study where the
subjects were given all their food."

"The DASH-Sodium study found that reductions in sodium intake produced
significantly lower systolic and diastolic blood pressures in both the control
and DASH diets. Study results indicate that the quantity of dietary sodium in
the control diet was twice as powerful in its effect on blood pressure as it
was in the DASH diet."

So, positive conclusions (lower salt -> lower blood pressure) in a seemingly
well designed study. People were randomized, it was prospective, and people
given all their food. So, change one thing and see what happens.

The author here seems to cite other studies to make the opposing case (low
salt = bad), but doesn't give exact references. I did a quick google search
and found this one:
[http://www.nytimes.com/2011/05/04/health/research/04salt.htm...](http://www.nytimes.com/2011/05/04/health/research/04salt.html)
But you can already tell it's an inferior study. "It involved only those
without high blood pressure at the start, was observational, considered at
best suggestive and not conclusive."

So, let's try to compare apples to apples.

He points out that the DASH study didn't conclude anything about death or
cardiovascular disease. Yes, that's true. So sure, there's a chance that
despite blood pressure reductions a low salt diet could cause problems. But
it's not the obvious conclusion. Anyone have any solid studies on this?

~~~
crazygringo
> _He points out that the DASH study didn't conclude anything about death or
> cardiovascular disease. Yes, that's true. So sure, there's a chance that
> despite blood pressure reductions a low salt diet could cause problems. But
> it's not the obvious conclusion._

That's the whole point, you say it yourself. The idea that "salt is bad" has
just as shaky underpinnings as "lower blood pressure is good". The only thing
we care about is death or disease, not lowering blood pressure. So even if
less salt = lower blood pressure, that doesn't tell us if this is good, or
harmful.

The obvious conclusion is that there _is_ no conclusion.

~~~
arn
> The idea that "salt is bad" has just as shaky underpinnings as "lower blood
> pressure is good".

Wait, "lower blood pressure is good" has shaky underpinnings? Is there a
debate on that? I don't think there's a debate that high blood pressure
results in worse (death/disease) outcomes.

~~~
joe_the_user
_"Wait, "lower blood pressure is good" has shaky underpinnings? Is there a
debate on that? I don't think there's a debate that high blood pressure
results in worse (death/disease) outcomes."_

There's no debate that high blood is _associated_ with heart disease. There's
always "a debate" if you try to go from correlation to cause. You always have
to be careful this.

You have to show that a particular mechanism for lowering blood pressure
results in better outcomes. You can't unambiguously say "we've lowered the
blood pressure, we know the results will be better now".

~~~
arn
I acknowledge that jumping from a to b to c (low salt to low blood pressure to
less death) has gaps in causality. But why do you not take objection to his
uncited assertions that low salt intake and bad outcomes together imply
causality?

~~~
gruseom
Where in the article does Taubes assert that? All I see him asserting is that
more than one hypothesis is plausible and the evidence is contradictory.

------
jswinghammer
As someone who has lost around 40 pounds of fat switching to the high fat
paleo diet I'm not at all surprised that the current state of the conventional
wisdom on food is wrong in any number of ways. It is funny that we really have
no idea what we should be eating naturally at all.

Grains were making me sick and I didn't notice for years. It wasn't until I
read a book listing side effects of grain consumption that I considered that
the grains were the cause of my problems.

~~~
mark_l_watson
I believe that we all have unique metabolisms and the real "science" is the
personal study of how we feel physically correlated with what we have been
eating, amount of exercise, lack of tension, etc. I ended up as a vegetarian
(with a little fish) because I kept track of how I felt and compared with
recently eaten food. I have friends who thrive on high meat diets. We are all
different.

~~~
rubashov
A lot of people "feel" fine but blood work shows they're insulin resistant,
have various deficiencies, or are loaded with cortisol. Going by "feeling"
really doesn't work. Also, the evidence against a vegetarian diet is
overwhelming.

~~~
ktizo
_the evidence against a vegetarian diet is overwhelming_

Someone better warn the Buddhist monks, they've been at it a while and if only
they'd known they might have lived a bit longer.

~~~
gurkendoktor
There are many vegetarian Buddhists here in Taiwan and their food is sadly
well-known for being overly greasy (as to add flavor). It doesn't help that
the local Buddhists avoid onion and garlic, two staples in non-vegetarian
local food. It's considered normal to eat supplements, but that's of course a
recent phenomenon.

I'm not saying it's all bad (I'm mostly vegetarian), but the studies are all
over the place as with everything in nutrition :)

~~~
Tyrannosaurs
There are so many varieties of vegetarian diet the term is a little
meaningless in terms of understanding nutrition.

I've been vegetarian for about 20 years, I eat a lot of fresh veg, not much
fried stuff, not much processed stuff, try and make sure I mix things up and
get some protein. Broadly speaking I think I've got a pretty good diet.

But I also know vegetarian's who are massively overweight, eat crap (and too
much of it), drink too much and so on.

As a broad group I suspect vegetarian's eat better but I think that's more
likely to be linked to the fact that this is a group of people who have
thought about what they eat as much as anything inherent in the lack of meat.

~~~
gurkendoktor
Right. Studies about vegetarians could only uncover those deficiencies that
would affect _all_ veg*ns, but I've never seen any that did.

~~~
Tyrannosaurs
And that would be interesting (and I think they do exist - I'm curious about
the poster above saying that they show it's not healthy because my
understanding is precisely the opposite), just I think that there are other
factors you need to control for to really understand it.

------
3pt14159
Sort of an aside here, but salt and MSG should be used to increase the
tastiness of otherwise bland foods, like asparagus, so that what you eat is
more in line with what your body needs, rather than what is the most tasty in
our post-industrial world. That is how I use salt: reduce starches and refined
grains, and increase vegetables, lentils, and the like. Sure I still have
_some_ bread and a normal amount of meat (at least by Canadian standards), but
I prefer to make healthy foods delicious.

~~~
muraiki
We might also want to think about _why_ some foods taste bland. I feel that
I'd never really tasted what a tomato tastes like until I had some at a
monastery in Greece.

I was surprised to see tomatoes sitting out at dinner, seemingly to be eaten
as-is along with the meal. I bit into one and it had a flavor unlike any
tomato I've ever had in the USA. I could finally understand that a tomato is a
fruit! It was nicely sweet with no bitterness and no discernible acidity.

In the USA when we ship stuff across the country, gassing it to stop it from
ripening, and then gassing it again to cause it to ripen again -- all the
while eating things mostly out of season -- it's no wonder that our foods
taste bland!

~~~
Alex3917
The other part of it is that if your body is used to a high calorie diet with
lots of sugar and fat, vegetables are going to taste bad no matter how good
they are. And if you're eating healthfully, then even supermarket vegetables
will taste reasonably good.

~~~
muraiki
That's true. I remember when I stayed in Japan for a while, initially I found
the food underwhelming. It turns out that good 'ol Japanese homecooking isn't
designed for the American palate, which is accustomed to lots of sugar, fat,
and calories. After a month, though, I loved the food and tasted all sorts of
subtle flavors in the vegetables.

Once I came back to America, I found that food here was overwhelming my
tastebuds. In particular, I remember trying to drink some Pepsi. It tasted
like I was drinking pure sugar (well, I guess that's what it really is). I
couldn't even finish it or any other kind of soda. Now I'm able to drink stuff
like that again, but that's probably not an improvement. :)

------
Cushman
All right! Next up: MSG.

Even those of my friends who know that the health concerns are bogus have a
weird paranoia of MSG. I think it's a general suspicion of any chemical which
makes food taste better (which somehow doesn't apply to salt and sugar).

~~~
fein
I think part of the problem with MSG is the name. It's hard to convince the
general public that something with the name "Monosodium Glutamate" is a
naturally occurring substance, let alone one of the more abundant naturally
occurring amino acids.

Hell, if we called table salt "Sodium Chloride" all the time, people would
probably have a bit of a changed perspective.

None the less, MSG is delicious!

~~~
Cushman
I think that's the idea behind the "All Natural AC'CENT® Flavor Enhancer"
branding-- they don't say "monosodium glutamate" _anywhere_ on the package
except the ingredients.

I just call it _supersalt_. Because it's like salt, but not salty!

~~~
fein
Technically, MSG is supposed to be the "extra" taste area they didn't know
about/ teach in school. So although it seems salty, it's actually the savory
flavor. MSG is found in just about every single food you eat that has that
"savory" flavor.

~~~
whatusername
The "Extra" taste is called Umami: <http://en.wikipedia.org/wiki/Umami>

Also -- despite what you may have learned in school -- the taste buds aren't
mapped to areas: <http://en.wikipedia.org/wiki/List_of_common_misconceptions>
(Search for Taste for links to the relevant sources)

~~~
Cushman
To clarify, since your parent didn't actually misspeak-- There are actually
only five main tastes your taste buds can detect. They just aren't organized
by location.

------
alecdibble
I have always wondered why so many facets of "institutional health" are
promoted as the status quo even with much contradictory evidence or lack of
"common sense".

A couple of things that come to mind: salt saturated fats sugars

I know many instances of this problem have to do with monetary interests. But
salt? Who gains from low salt intake? Reputation? Or is it something else.

~~~
Cushman
Taube's theory (about cholesterol, but I think it applies here as well) is
that it's "where the light is". Things which are measurable are optimized for
even if they're pragmatically pointless.

So a study comes along that finds a correlation between sodium intake and
cardiovascular disease. Totally possible. The USDA looks at those numbers and
says, we're eating Xmg of salt, we should be eating Ymg. They make a
recommendation, years go by, and they look at the numbers again and, hey, salt
consumption is down to Ymg! Success!

What about mortality? Who knows. That's not their department.

------
gouranga
TBH my general health has improved after I stopped giving a crap about rules
and regulations and just eat when I need to not when I want to. Determining
between want and need is the hard bit.

------
dbbolton
Increased blood osmolarity will lead to an increase in blood volume, period.
If you add fluid to a closed system, the pressure of that fluid on its
container will increase. However, in most cases, excess solutes should be
excreted relatively quickly and blood volume will return to normal.

~~~
goostavos
>If you add fluid to a closed system, the pressure of that fluid on its
container will increase.

Does the inverse hold up as well (in regards to the human body)? If people
have high blood pressure, if the gave a couple of pints of blood each month,
would that do anything to lower the pressure?

~~~
dbbolton
Of course it would lower the pressure temporarily, until the body restored
blood volume to normal levels. But hypertension is defined medically as a
chronic condition.

------
teeray
"If it disagrees with experiment, it is wrong"

<http://www.youtube.com/watch?v=RXABcv9djQ0>

------
harrisreynolds
The harsh reality is that there are so many variables when it comes to diet
and nutrition information that formal studies are close to worthless. That is
why I find information like the studies Weston Price did [1] interesting. His
conclusion was that any society on a whole food local diet was generally
healthy and that pre-mature physical degeneration only happened when
"primitive" diets were replaced with "modern" diets (i.e. highly processed).

Here's a simple rule. If you could find/grow it in your back yard, eat it. If
not don't.

[1] [http://www.amazon.com/Nutrition-Physical-Degeneration-
Weston...](http://www.amazon.com/Nutrition-Physical-Degeneration-Weston-
Andrew/dp/0879838167)

------
gregwebs
There is a good overview of evidence on salt in this series of articles:
[http://chriskresser.com/shaking-up-the-salt-myth-the-
dangers...](http://chriskresser.com/shaking-up-the-salt-myth-the-dangers-of-
salt-restriction)

Gary Taubes (author of this article) goes over the evidence on salt
restriction in more detail in Good Calorires, Bad Calories, but it is missing
some recent studies indicating negative outcomes for salt restriction. I
believe Taubes is often wrong (as most people are) when proposing his
hypotheses. But he is very good at tearing down wrong hyptoheses.

------
brm
This is the best, most reasonable thinking I've read on this study (From Jay
Parkinson, the M.D. behind the startup sherpaa.com)
[http://blog.jayparkinsonmd.com/post/24488678085/when-i-
read-...](http://blog.jayparkinsonmd.com/post/24488678085/when-i-read-that-
something-is-good-or-bad-for-you)

------
jiltgeis
The important thing to remember is that processed salt, which is devoid of all
minerals and trace elements is not the same as good-quality natural sea salt,
which does contain the trace elements and minerals and is able to be absorbed
by the body more easily. Processed salt actually saps the body's mineral
reserves and is very hard on the body. In colder harsher seasons for those
living in temperate climates, more (good quality) salt is necessary than for
people living in the tropical regions for example. Moreover, practically all
general restaurant food has entirely too much processed salt content and will
actually age you overnight.

------
aero142
There was an idea in 'Fat Head' where the narrator pokes fun at the idea that
we are a species who's evolution has made us so that we crave foods that are
actually killing us. It's not proof that we can't crave foods like sugar, fats
and salt that might be harmful to us, but I think it sets up a health amount
of skepticism towards the idea that our innate cravings are in fact harmful.

~~~
patrickk
" _...we are a species who's evolution has made us so that we crave foods that
are actually killing us._ "

" _...it sets up a health amount of skepticism towards the idea that our
innate cravings are in fact harmful._ "

It's modern processed food that's harmful.

We evolved to cope with the amount of salt, sugar, carbohydrates etc. that was
readily available to our ancestors on a hunter-gatherer diet (we would've
reached an evolutionary dead end otherwise if our "innate cravings" were not
useful to us in a survival sense) - you would have to do a lot of hunting and
gathering to get the amount of salt, sugar, saturated fat etc that a single
fast food meal provides - it was relatively rarer so we have cravings to
ensure we got enough of them back when they were scarce.

Evolution is a very slow process. Adding syrup to carbonated water,
advertising the crap out of it and selling it at huge markup (coca-cola) can
happen over the course of a single human's lifespan.

~~~
aero142
Salt is a very important part of a human's diet and was a major trade item for
all of recorded history. Salt has been used as a preservative for meat for as
long as I'm aware of. Animals often sit and lick natural salt deposits.

There is a common belief that meat and especially fat are bad for you and
cause heart disease, which is the particular idea that Fat Head makes fun of.
He reduces his carb and sugar intake and lowers his cholesterol and loses
weight.

I quit drinking soda and reduced my sugar intake because it made me feel bad.
I sometimes crave sugar after running a lot or when I'm tired and I will
occasionally drink a soda, but I usually regret it. Same with candy etc.

I can only speak for myself, but the idea that my natural cravings and the
reaction of my body are good indicators of what is healthy has been very
successful for me. I currently believe that fat and meat, plus vegetables are
very health and I crave all these things. My body is very sugar sensitive and
so I avoid it because of how I feel. The guide that my evolutionary tastes are
not trying to kill me seems to be a pretty good guide towards finding a
healthy diet, and I believe it will serve me better than the National Health
Services recommendations have. If you believe that there is good reason that
evolution may be guiding you towards something unhealthy, you may be right,
but my default answer is the it is correct unless there is a better
explanation.

~~~
patrickk
" _If you believe that there is good reason that evolution may be guiding you
towards something unhealthy..._ "

I don't think there's any doubt about this. Compared to evolutionary rates,
the typical diet in the west has changed at lightning pace from just a few
decades ago, meaning our bodies and taste buds are behind the curve. We need
willpower and common sense to have a healthy diet, rather than raw survival
instincts.

Unfortunately what's driving change in our diet is the demand for companies to
serve food with high profit margins and low cost raw materials (e.g. high-
fructose corn syrup). Capitalism is great for providing us with cheaper
clothes and ever-cheaper computing power, but providing cheaper food means
providing crappier food. There's no Moore's Law for food.

I think it was here on HN I read about studies done in remote communities
(possibly some remote whaling community) that had recently become westerised,
and the diet quickly shifted to one more similar to a typical American diet.
Within 5-10 years (or a relatively short time frame, can't remember exactly)
obesity and type-II diabetes rates exploded.

Another interesting story was reports from surgeons who operated on injured
Afghan fighters from the current conflict. Normally when operating on
westerners, you expect a certain amount of yellowish fatty tissue surrounding
the major internal organs. This wasn't present on Afghan locals, which
surprised the surgeons who were so used to seeing it on western patients and
pretty much assumed it was normal up till that point. The difference was down
to diet.

~~~
aero142
I like your comment but you are confusing the issue. Your argument is that
processed food is bad for you and cheaper because of production scale and I
completely agree. My point is that if I take two meals and put them in front
of someone, one with a red steak wrapped in bacon and vegetables and one is a
hamburger and fries, I suspect most people will chose the high fat meat and
veggies. However, the government has been pushing the food pyramid
<http://www.nal.usda.gov/fnic/Fpyr/pmap.htm> as a school indoctrination
program for as long as I can remember. As far as I can tell that hamburger
fits right in with your six to 10 servings of bread a day, and they would tell
you it's the bacon that is making you fat and giving you heart disease. So
yes, cheaper food is worse for you generally speaking but that is about
economics, not evolutionary tastes.

------
aurelianito
Am I the only one who saw this title and thought about salted password hashes
stored in a database?

------
artsrc
This misinterpretation of what the authors of the study Cochrane should have
said, led to the conclusions being re-written to conform to what was actually
found:

<http://www.bbc.co.uk/programmes/b0138yld>

------
Meiscooldude
Fat Head (2009) <http://www.youtube.com/watch?v=LgBLQIJEcbE>

------
gantz
Is there at all a system to try to compare studies or evaluate how apples to
apples they are?

------
singingwolfboy
Everything in moderation.

~~~
Karunamon
Seriously, almost all of modern food/health science could be reduced down to
this simple phrase. Eating too much of "X" is bad for you. No, really? Ya
think?

Even cigarettes in moderation won't kill you.

~~~
frankc
I don't mean to beat this to death, but any kind of statement about moderation
presupposes that we already understand how different amount of some substance
will effect us. The topic under discussion boils down to "what is too little,
what is too much and what is moderation?". You cannot answer that with "just
go for moderation" when moderation is precisely what we are trying to define.

I see this kind of thing all the time and it irks me because I see so much
agreement with what amounts to a circular statement.

------
tripzilch
People should just learn to use bcrypt to season their food.

