Salt, We Misjudged You

http://nytimes.com/2012/06/03/opinion/sunday/we-only-think-we-know-the-truth-about-salt.html

by gruseom • 14 years ago

314 157 14 years ago

Everything in moderation.

Karunamon• 14 years ago

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.

gfosco• 14 years ago

I had fun debating the cigarette thing with my doctor.

frankc3• 14 years ago

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.

frankc3• 14 years ago

No offense but this is really an intellectually weak statement because moderation is dependent on what is considered "too much", and here we are looking to redefine just what "too much" really is.

gruseom2• 14 years ago

That's a tautology. The question is, what counts as a moderate intake of salt?

If Taubes is correct, average US salt intake is moderate. The government says it is excessive.

abtinf• 14 years ago

Everything in moderation. Extreme moderation.

mikeash2• 14 years ago

Everything in moderation, especially moderation.

teeray2• 14 years ago

"If it disagrees with experiment, it is wrong"

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

jswinghammer7• 14 years ago

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.

mkoivuni• 14 years ago

Agreed, nutritional "science" and conventional wisdom has become a joke.

frankc3• 14 years ago

It should be noted that the author of the linked article is Gary Taubes, who is best known for Good Calories, Bad Calories, a book that seeks to turn the conventional wisdom of nutrition on its head.

drostie• 14 years ago

I just wish we could see more directly a sense of how little we know about good nutrition.

My favorite example is Vitamin B12, mostly because I learned the story when I reduced my meat consumption to about once a month. So there's this family of massive molecules containing the metal cobalt which we can't make on our own because we're not adapted to eat cobalt, and they're all called "Vitamin B12". It helps in the last step of making the protein building-block called methionine; if you get malnourished in this way your body just basically fills up with "almost finished" methionine which is useless and might even be poisonous. There can also be a slight risk of nerve damage although as I understand it we don't actually understand why the hell that would be.

The biggest cause of malnutrition in this sense is simply being old -- you can't absorb Vitamin B12 so well in the first place because it is huge and weird, and old people have even more trouble either because their gut is slowly dying or because they're infected with H. pylori, which is a safe bacteria more than 80% of the time and might even be important for a well-functioning stomach, but might sometimes cause a chronic tummy-bug.

Okay, so that's the problem, but what do we know about how much of the B12s we need and get? We know very little. The US Recommended Daily Allowance of B12s is 2.4 μg, but the US Daily Value for B12 is 6.0 μg. How much do you get in your food? You get almost none from vegetables, and vegans are basically all ipso facto suffering from B12 deficiency unless they take supplements or eat enriched cereal -- but most of them are quite healthy and see no problems from it. As for vegetarians like (almost-) me, the exact range for milk and eggs to get to this limit is imprecise because the limit itself varies by a factor of 3, so you might need to eat three eggs per day or else ten; so you might need to drink two cups of milk per day or else five, to live up to those numbers. So in theory there are lots of vegetarians also who come in at half or one-third their daily requirement, and never notice anything. Meanwhile there are people over 60 who eat plenty of meat but are starting to feel the effects anyway.

We actually don't even know how well you absorb it. A USDA researcher named Lindsay Allen did a 2011 study where she marked Vitamin B12 in eggs so that she could detect it, and then fed those eggs to 10 people. She found that the body absorbed 50% of a 1.5 μg dosage but only 20% of a 2.6 μg dosage. Let me repeat that. She found that, in absolute value terms, eating more B12 led to less of it being absorbed, 0.75 μg versus 0.5 μg. It's probably not statistically significant with 10 people, but still. We don't even know that eating more leads to you absorbing more of it. (I also wonder whether RDAs are "amount absorbed" while DVs are "amount eaten", as this is pretty much never reported, but I will assume that they aren't crazy and that it's always "amount eaten.")

I wouldn't use the scare-quotes around "science" when talking about nutrition science, as I think there is potential for real research here and I think people do indeed do it -- but it's a lot of work before we have a firm understanding, and most of that work hasn't been done yet, and yet you hear these confident conclusions. I would just like to hear people publish standards in the form, "you might need this much, or that much, we don't really know."

The engineer in me craves error bars. Where are the error bars?

merlincorey• 14 years ago

I always knew salt and vinegar chips were good for me!

heretohelp• 14 years ago

High-fat paleo diets avoid starchy/carby foods like chips fyi.

rubashov2• 14 years ago

Well Loren Cordain, godfather of "paleo", remains convinced that salt is bad. He claims the chloride does some bad stuff (I forget) and also the sodium screws up potassium and magnesium levels somehow.

jswinghammer7• 14 years ago

I avoid processed foods as a rule so it's hard for me to get a lot of salt anyway. I really don't worry about it one way or the other.

einhverfr5• 14 years ago

I don't there can be much doubt that improper ratios of sodium in the body can be bad. In particular I'd look at the ratio of sodium to potassium. But the same goes the other way too. Being sodium-deficient is really not fun. I know from experience.

Sodium and potassium have a significant number of important roles in the body and they are balanced against eachother. Too much sodium will mess up the potassium functions and vice versa.

Panoramix2• 14 years ago

Which book was it?

wusher• 14 years ago

Most likely The Paleo Solution. That's the one that turned my diet around.

jswinghammer7• 14 years ago

The Primal Blueprint is the best source of information on this approach. It's less of a diet and more of a lifestyle change. It was a great read.

mark_l_watson• 14 years ago

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.

jswinghammer7• 14 years ago

I believe it. For me wheat really messes me up but white rice is fine. I eat it now and then because I like it so much. Whatever works.

rubashov2• 14 years ago

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.

gurkendoktor3• 14 years ago

I'd even guess that people who are happy and at peace with what they eat might outlive hardcore perfectionists. Are there any studies about that? (I'm thinking of a parallel to the study where religious people lived longer.)

einhverfr5• 14 years ago

Of course statistics dont necessarily translate to the individual. But to further agree with you I would point out a rather nasty (I think) trend in medical science, which is to treat individuals who diverge from the statistical models as defective.

Look up the medical literature for "Cytochrome P-450 defects" for example. What folks are typically talking about here are differences in rates of metabolizing various pharmaceuticals. Some people like are considered defective because we process many medicines very slowly. Personally I think this is great. I take less medicine, and I suspect it may be why constant moderate drinking (alcohol) eventually makes me mildly sick and I have to stop for a while. It's great. Except that it's called a defect by pharmaceutical researchers.... and there's even experimental gene therapy to correct it.

conradfr2• 14 years ago

While researching a bit about the interaction between ADHD and food, I stumbled on articles about that kind of diet.

My (real) question is : what do you eat and how do you keep pleasure in eating ? From breakfeast to super, how can you even avoid bread (and cheese), the best thing on Earth ? It seems so impossible to me.

bad_user3• 14 years ago

I am not on a paleo diet. Instead I'm on a dissociated diet and I lost 42 pounds since February.

I do not avoid diary products. I do avoid bread, but when I do eat bread, I prefer bread that's made of whole grains. And so I'm making my own bread. In general I follow these 2 rules:

(1) I stopped eating refined carbohydrates or preprocessed crap (entirely, no exceptions ... all the sugar I want comes from fruits)

(2) I never combine food rich in carbohydrates with meat or diary (I eat potatoes for instance, but without meat)

As to your question on how can you give up bread: refined carbohydrates give you a dependence, just like nicotine. The more you consume, the more you crave for more. When you stop eating bread daily, you simply will stop carrying about bread.

jswinghammer7• 14 years ago

I find things that work for every meal and try new recipes. Bread tastes great but I avoid it because if I eat it then I will pay a heavy price. Try the primal blueprint for 60 days and see what happens. I noticed a huge change in 24 hours but my results are not typical.

einhverfr5• 14 years ago

One of the most interesting things is how many sciences inform archaeology, and how few sciences are willing to be informed by archaeology.

High grain diets archaeologically are associated with increased tooth decay and tooth loss rates and lower life-expectancy than high-meat and high-dairy diets. Overly high dairy diets are associated with anemia (probably because cow milk decreases the ability of humans to absorb iron from foods). The Vikings were eating butter smeared on dried fish for breakfast and living significantly longer (and with very low rates of dental caries) than the grain-eating Continental Europeans of the same time. Indeed a Scandinavian living to 5 could expect to live to an older age than a Frenchman living to 20 despite the fact that life expectancy was so heavily slanted by childhood deaths in both cases.

Our conventional wisdom of nutrition is basically plausible hypothesis... if you ignore anything interdisciplenary. I think the archeologists know more about the effects of nutrition on the human body today than anyone else.

3pt141592• 14 years ago

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.

riffraff2• 14 years ago

just FYI, in the pre-industrial world of my home town you can still go picking up wild asparagus[1] which are _far_ from bland, I have no idea if those exist in any form where you live but I strongly advice you to try them out if you can.

[1] stuff like this http://3.bp.blogspot.com/__88ZCQ5jRIs/Sju4DrHvsZI/AAAAAAAAg1...

NoPiece• 14 years ago

That looks amazing, but wouldn't you season it? A little olive oil and salt then throw it on the grill for a minute?

streptomycin2• 14 years ago

> salt and MSG should be used to increase the tastiness of otherwise bland foods, like asparagus

False. Asparagus (like many vegetables) should be roasted with garlic in a little bit of oil.

3pt141592• 14 years ago

Heh. I never boil 'em, always grilled on the Barby or roasted in the oven and garlic is delicious.

muraiki2• 14 years ago

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!

smsm422• 14 years ago

I started eating vegetables without salt many years ago, and once I got used to it, they don't taste bland to me at all. Even the regular grocery store ones. Of course, if you get homegrown organic ones, they are way better - but even the grocery store ones still have a lot of taste, unless your taste is ruined by years of training it that vegetables should taste like salt. I actually hate when more than a trace of salt is added to the vegetable salad - then only thing I can taste is the salt, it overwhelms everything else.

Alex3917• 14 years ago

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.

ronaldj• 14 years ago

My parents grew tomatoes in their garden every summer here in the US. I've been eating tomatoes like that since I was a child. Sliced, as a side, in the summer, with a little salt and pepper. I only do this when they are homegrown though.

alecdibble• 14 years ago

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.

Cushman7• 14 years ago

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.

teeray2• 14 years ago

Not to sound like I'm putting on my tin-foil hat, but a lot of money floats around in this space. It's entirely possible for a segment of the food industry to be viewed the same as cigarette companies if extensive studies show that, for example, eating cereal is actually killing you. No company wants that death sentence, pun not intended :-P

Cushman7• 14 years ago

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).

fein2• 14 years ago

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!

Cushman7• 14 years ago

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!

ticks2• 14 years ago

Conversely, it winds me up when products boast that they have no artificial ingredients, yet have colours or flavours which are mixtures of natural substances that have little to do with the products that they are being used to imitate.

kijin• 14 years ago

You're probably right. Did you know that dihydrogen monoxide kills thousands of people every year? That substance has been found in the blood of every terrorist and serial killer in human history. Scary stuff if you put it that way.

MartinCron4• 14 years ago

One way to look at MSG (the way I look at it) is that it has been shown to stimulate the appetite. As a result of this, people often eat MSG-infused food more than they should. My wife once said that MSG "makes me think this tastes better than it really does".

So, MSG may or may not be bad by itself, but the highly processed empty calories that it hangs out with, definitely bad. Bet you can't eat just one? I don't take that bet anymore, I lose too often.

Cushman7• 14 years ago

I think that's exactly what I mean by "paranoia". It's certainly true that MSG makes food taste better than it "really does", and makes you want to eat more-- as do added salt, sugar, or any seasoning for that matter.

For some reason only in MSG does this quality inspire distrust.

aero1423• 14 years ago

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.

patrickk2• 14 years ago

"...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.

ticks2• 14 years ago

Indeed. Some processing is good, but a lot of it just makes the food too easy to eat. I would argue that even processing food at home, such as mashing potatoes can be a problem unless you are careful about the portion size - i.e. remember how many potatoes were used to make it.

aero1423• 14 years ago

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.

mikeash2• 14 years ago

Our bodies are full of feedback systems that only work in our natural (i.e. pre-civilization, pre-agriculture, hunter-gatherer, nasty, brutish, short) environment. It should be no surprise that our food cravings are among them.

There are other fun examples. One is that our breathing reflex is based on CO2 concentration being too high rather than O2 concentration being too low, even though O2 concentration is more important! Breathe into a closed system with a CO2 scrubber in it and you'll quickly get loopy and then pass out from lack of oxygen (and then die, if nobody disconnects you) all the while feeling fine. Another is that the iris of the eye responds to visible light but protects against more. Looking at the Sun is normally OK (uncomfortable, but tolerable) because the feedback is set up properly, but during the totality of a solar eclipse (which of course occurred back then, but not often enough to matter, apparently) your iris will crank open and let in tons of UV from the Sun's still-visible corona, frying your retina if you look at it.

It makes a great deal of sense that we'd evolve strong cravings for things which are good for us in small quantities but bad for us in large quantities when those things were scarce in the distant past, and death came early by other means for other people, well before a bad long-term diet could kill. That doesn't mean this must be what happened, but given how much humans love sugar, and how rare concentrated sugar would have been for our ancestors, it's no surprise if sugar turns out to be bad for us when consumed in the quantities we really want.

arn4• 14 years ago

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... 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?

streptomycin2• 14 years ago

> I always cringe a little when I read medical conclusions in the mainstream media.

I usually do too, especially articles about nutrition which are notoriously unreliable due to the near complete lack of randomized, controlled, prospective studies and the abundance of observational studies, but this one doesn't seem too bad. In fact, the same author published a similar article in Science last millennium http://www.stat.berkeley.edu/users/rice/Stat2/salt.html so I don't think you can blame the mainstream media too much here if they're just printing an article similar to what would satisfy Science's editorial standards.

cperciva• 14 years ago

there's a chance that despite blood pressure reductions a low salt diet could cause problems

For that matter, there's a chance that because of blood pressure reductions, a low salt diet could cause problems -- if the kidneys respond to low blood pressure by secreting renin, and renin causes more cardiovascular damage than high blood pressure.

splat• 14 years ago

Taubes has written a bit about salt before. Unfortunately, the only thing he's written that I can find that goes into more detail is this Science news focus article:

http://www.sciencemag.org/content/281/5379/898.full

It talks about the DASH study and some others in a little more detail, but unfortunately it's 14 years old now, so I don't know what research has been done since.

ellyagg• 14 years ago

Scientific American has also had a couple articles about this recently. Here's one:

http://www.scientificamerican.com/article.cfm?id=its-time-to...

crazygringo• 14 years ago

> 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.

arn4• 14 years ago

> 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.

grannyg00se• 14 years ago

Isn't blood pressure a symptom, or an indication of other processes going on? Why would you want to directly manipulate the measuring tool?

artsrc2• 14 years ago

The studies are not conclusive.

Populations with low sodium intake, and other factors, have no hypertension, and low rates of death and disease from heart disease.

The randomized studies have found lower death and disease from lower sodium. So far the probability that this is just chance is about 10%. So the standard p number is not reached.

The most likely outcome is that a bigger better studies will produce significance.

Symmetry• 14 years ago

I believe the contention is that studies like DASH show that changes in sodium consumption, rather than levels of sodium consumption, can effect blood pressure. That is, if you go onto a low sodium diet your blood pressure will fall, but then rise again to its previous level as your body adjusts.

joe_the_user2• 14 years ago

Uh,

He points out that the study followed people for 30 days.

And made recommendations for life-long behavior.

And wasn't looking at final results but markers (blood pressure).

And was the main argument against salt consumption when we do have some data on people's life-long behaviors and their result.

And this wasn't "medicine" that spoke but a particular institution making recommendations.

Edit: removed possibly inflammatory point

alan-crowe• 14 years ago

I think that the Cochrane reviews mentioned are these two

http://summaries.cochrane.org/CD009217/advice-to-reduce-the-...

http://summaries.cochrane.org/CD002128/dietary-advice-for-re...

blantonl• 14 years ago

nephrologist = branch of internal medicine and pediatrics dealing with the study of the function and diseases of the kidney.[1]

[1] Wikipedia: http://en.wikipedia.org/wiki/Nephrology

niels_olson2• 14 years ago

arn, thanks for leading this one! Let me chime in that salt no doubt drives caloric intake. One need look no further than chefs and fast food to figure that out. So, in my mind, salt is a double whammy: BP and a secondary cause of weight gain, cholesterol, and everything else that comes with weight gain.

rsheridan6• 14 years ago

If you look at the numbers in the Wiki link you provided, the reduction in BP in DASH dieters was small in non-hypertensives and not exactly huge in hypertensives.

"Respectively, the DASH or “combination” diet lowered blood pressures by an average of 5.5 and 3.0 mm Hg for systolic and diastolic, compared with the control diet. The minority portion of the study sample and the hypertensive portion both showed the largest reductions in blood pressure from the combination diet against the control diet. The hypertensive subjects experienced a drop of 11.4 mm Hg in their systolic and 5.5 mm Hg in their diastolic phases."

I question whether the 5.5/3 mmHg is really worth eating bland low sodium food. Statistical significance does not necessarily imply clinical significance, and you're asking people to give up something pretty big. Willpower is a limited resource. We should have good reasons to ask people to use it up.

Here's an abstract of a metaanalysis which reaches roughly the same conclusion: http://www.nature.com/ajh/journal/v24/n8/full/ajh2011115a.ht...

einhverfr5• 14 years ago

I'd agree. I have had times in my life where I have had to increase my salt consumption to avoid problems. These include everything from altitude sickness to dehydration caused by eating a diet too high in fruit.

However, at the same time I don't think that things are as clear-cut as in the article. One of the serious issues we find in current dietary trends is that we eat more prepared foods which tend to be high in salt, hydrogenated oils, and sugars.

So I personally side both with the idea that we have gone overboard in trying to reduce salt and also the idea that the modern American diet tends towards too much salt. I would also make the somewhat controversial argument that I think that anything we replace salt with will be even worse. The solution is to eat more fresh foods and fewer junk foods and prepared foods, not try to engineer some sort of low sodium equivalents.

dbbolton2• 14 years ago

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• 14 years ago

>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?

dbbolton2• 14 years ago

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.

Meiscooldude• 14 years ago

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

gouranga• 14 years ago

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.

harrisreynolds• 14 years ago

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...

artsrc2• 14 years ago

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

gregwebs• 14 years ago

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

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• 14 years ago

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-...

aurelianito• 14 years ago

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

gantz• 14 years ago

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

jiltgeis• 14 years ago

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.

tripzilch• 14 years ago

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

Salt, We Misjudged You

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