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Link Between Salt and High Blood Pressure 'Overstated'
An anonymous reader writes: Diagnosed with high blood pressure? If so, you were probably told to moderate or avoid the use salt in your food. Well, a new study (abstract found that salt is not associated with systolic blood pressure after controlling for other factors. The study found that BMI, age, and alcohol consumption all strongly influenced blood pressure, and concluded that maintaining a healthy body weight was the best way to counteract it. The publication of this research follows a CDC report from Tuesday decrying the amount of salt in children's diets — a report that lists high blood pressure as one of its main concerns. The debate on this issue is far from over, and it'll take years to sort out all the contradictory evidence.
My wife.
CDC: "A vast majority of scientific research confirms that as sodium is reduced, so is blood pressure."
Which does not mean that salt *causes* blood pressure to increase.
Eat shitty food, which happens to contain a lot of salt, and you will have high blood pressure.
Eat good food, and add a ton of salt to it, and you will have normal blood pressure.
Anyone who has taken the time to experiment with their diet can see the results themselves (like I have).
Now I can go back to ramen noodles for lunch!
Of course. I read about this quite a few years ago in a book called Global Warming and Other Bollocks. It has a chapter on salt. I'm still recovering from being told that egg yolks are as bad for me as smoking, though I don't eat 20 eggs a day (or smoke any more), it turns out that actually they're probably only bad for people with heart disease or diabetes.
Anyone losing the will to live yet? I could go on...
Clearly, this indicates that the science behind anthropogenic global warming is flawed.
Just about everything that is bad for you today is being negated a few years later. Can't find the link today, but at one point "research" showed that jeans were responsible for higher risk of cancer. So I will just continue to live my life and enjoy it to the fullest. If something kills me, at least I had a good time.
To Terminate, or not to Terminate, that's the question - SCSIROB
But it does help with water retention, right? And you would imagine that as the body retained more water it would become generally more pressurised?
Troll is not a replacement for I disagree.
I'll take this with a grain of salt. Many years ago, "they" said the same thing about chocolate and greasy foods regarding acne breakouts. It was pretty evident to me and every single person I've ever known, including my own dermatologist (back in the day) that this was totally off-base wishful thinking, and the old "myth" was absolutely correct, whatever the biological mechanisms involved. The study was seriously flawed.
Look back up at my post, now look back down, you're on the Internet. Now look back up. I'm a signature.
I can tell you from personal experience having been a physical fitness health nut and also having gone through prolong periods of enormous stress that the two are undeniably linked. When you're under stress, you have fight or flight response. Several chemicals such as cortisol and adrenaline are produced in your body. When you're under chronic stress, you have this type of constant sense of this. It depletes resources in your body differently than when you're relaxed. It also causes you to store more body fat because when we were in the wild the environment stress response could be associated with food scarcity.
The time in my life when I was in the best shape of my life was when I was under the least amount of stress. I had low blood pressure, cholesterol, LDL/HDL, triglycerides, everything. My GP was cheering me on.
Get your stress under control and focus on having a healthy lifestyle and everything else will sort itself out. The problem in America is that we are a culture that pushes inordinate amounts of stress on our citizens. Where UK citizens would take a month long holiday every year because of the generous vacation time afforded by most European countries, the United States doesn't guarantee any paid vacation or sick time. And then we wonder why compared to other countries our citizens are significantly more tired, burnt out and less healthy.
We'll make great pets
those scientists were certain that salt was evil, bad, bad, harmful! Don't blow up my world view like this! Whenever the scientific community says something is so, it is so!
Way too many fad conclusions come and go in science, and especially with food. Eggs are bad, eggs are good, fat is bad, fat is good, carbs are good, carbs are bad, resveritol cures all, resveritol no better than placebo, Dr. Oz is a genius, Dr. Oz is a pocklining schill....
In the end it seems that if you wait about 10 years almost every headline on health gets contradicted, then thar contradiction gets at least qualified another 10 years after that.
Nothing so far has done better than simply trying to aim for eating plenty of real food with moderation on the highly processed stuff, and moderation on the calorie dense stuff.
The one thing about salt is that it does make stuff tasty, often the highly processed stuff, making it easy to overdo it. Avoiding salt sort of automatically helps one to cut out the heavily processed foods.
Then you just conveniently forget about the last time someone provided you with evidence. You just got through making this exact same argument, and someone dumped a ton of evidence on you. This is evidence you could easily have found yourself, and yet you repeatedly use the burden of proof to ignore the facts you've already seen presented.
How many times do you expect someone else to present the evidence to you?
Most likely there are people that have a considerably lower tolerance, or high tolerance, to salt, which leads to blood pressure changes.
I've known people eat salt out the ass and they are still healthy as you could be.
Then there are people that basically don't eat much salt at all and also have high blood pressures.
Salt most likely exacerbates certain conditions that aren't known yet, as well. (stress being a common known one)
There is still a lot of research with this to do. But going by the knowns, there is definitely a HUGE piece of missing information that gives a person high blood pressures, and salt may also affect one, or possibly even multiple, disorders.
This is not actually news though it's one more study on the pile. My wife is a physician and her instructors in med school pointed out that the relationship between salt and high blood pressure was based on correlations, not a causal chain. Basically it was a logical hypothesis that people started acting upon before it was ever established as fact. A lot of patients with high blood pressure problems (apparently - I'm not a doctor) have issues relating to osmotic gradients and other biological functions where salt is involved. So the theory went that by controlling sodium you could help control these problems. A good theory. But a good theory isn't a necessarily fact and it sounds like a lot of medical effort went into controlling sodium before anyone actually could test to see if it really mattered. Apparently the answer is turning out to be that it doesn't matter nearly as much as we thought.
Oblig XKCD
Being in the midst of trying to control mine, here is a basic explanation provided by my Endocrinologists with some help from Wikipedia.
It all comes down to the Renin–angiotensin system.
When the Kidneys think they don't have enough fluid volume to do their job, they send out signals that ultimately come back to themselves, causing them to retain salt and ditch potassium. Water, naturally, follows the salt and results in increased blood volume and subsequently, pressure. That's why many BP meds contains diuretics.
Too much salts mucks up all the complex feedback mechanisms.
Something that is apparently under diagnosed is a condition called Aldosteronism, where the adrenal glands make too much of a hormone called aldosterone, a primary messenger in this cycle. Aldosterone levels are not part of the standard blood workup done by your average family physician and diagnosing the condition requires a special, hours long process. It's is kind of a Zebra in diagnostic terms but is looking more and more like a horse.
So if you are afflicted with High BP and you're not having much luck controlling it, ask your doctor about aldosterone levels. High BP that is a result of this condition is more dangerous in the long term, but possibly curable by suppressing the aldosterone or removing one of the adrenal glands.
When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
The debate on this issue is far from over, and it'll take years to sort out all the contradictory evidence.
Once again, science is reduced to debate and belief. Medicine is rife with these sorts of "schools of thought"(*), it's almost as bad as economics. This is not the "more refined theory supplants approximate theory" that one finds in, for example, physics. It's "yeah, this looks good and makes sense, so we're 'gonna go with it" science.
This is what allows vested interests to decry science in favor of their own agenda. Who is the average person supposed to trust when scientists keep making and overturning bad conclusions, in the face of authority figures pushing their own agenda?
All I see here, in this forum, is appeal to the difficulty of experimentation. If the original single experiment is so hard or expensive to reproduce, should we be basing our conclusions on the single experiment?
Scientists need to kick it up a notch.
(*) As a typical example (dozens more are easy to find), Helicobacter pylori was identified as the source of gastric ulcers, yet the medical community didn't believe the results for many years. The amount of suffering and loss that occurred while this "school of thought" was slowly overturned is incalculable.
But it does help with water retention, right? And you would imagine that as the body retained more water it would become generally more pressurised?
As I understand it, that is a big part of the basis of the theory behind controlling sodium in heart patients. Osmotic gradient controlled through reduced sodium. Good sounding theory. However just because that sounds sensible doesn't mean it actually matters in medical outcomes. The human body is complicated and sometimes good sounding theories turn out to be completely incorrect. This appears to be one of those good sounding but false theories.
The problem is that "high blood pressure" refers to two different things: 1. your blood pressure is above the normal range (120/70) at a given time and 2. you have chronic hypertension - your blood pressure is *always* above the normal range. Eating a bunch of salt can temporarily raise your blood pressure due to water retention but there's never been any evidence that this temporary effect has any long-term effects. Chronic hypertension is normally caused by poor health habits, particularly in regards to having excess weight. Eating salt has nothing to do with it.
I deal with this all the time because my wife the RN was always taught in school that eating too much salt leads to "high blood pressure". Well, yes, by definition "1" above. But that's a temporary condition and there's no evidence that it's bad for you. It took me 10 years to "unteach" her this little factoid, and I still have to deal with her telling the kids to not eat too much salt "because it's bad for you."
The only way to solve this long term is to use only the term "chronic hypertension" to refer to the chronic condition.
Do you have ESP?
Finally, some truth. Did you know that salt isn't bad for you if you're not fat? Because you were probably taught the opposite. Although this article itself is wrong. Salt does not raise blood pressure. The amount of water you drink after eating salt raises your blood pressure. It's only like a couple hour thing though. 24 hours max.
There was an increase in hypertension
there are many other study's that show there is a link.
Too much salt has other effects beside blood pressure, so to tie this to the CDC report seem disingenuous.
The Kruger Dunning explains most post on
Bring me more of these... Salted. I work better with salt.
Did you know that in the 20th century they actually thought that salt was bad for you?
Listen to the animals I say. The lion will sit down with the lamb to share the salt lick.
Good enough for them, good enough for me.
Max Eilerson, Crusade, 1999
How can I believe you when you tell me what I don't want to hear?
My physiology professor explained it to me years ago. There's two reasons. First, we're told to cut salt not because salt is bad, but because we eat shitty food filled with salt. Telling people to avoid salt is easier than telling them to avoid bad foods. Second, 10% (or 25% according to UVA) of the population is salt sensitive, but there's no "easy" test for it, so doctors tell people to avoid salt anyway.
I guess there's really only one reason: telling people to avoid salt is the easy answer that gets results. I can see other comments already that swear "but scientists told us salt was bad!" Yeah, they lied to us sort of, because figuring out what food is healthy and what food is not is too complex for the general populace. They simplified it to unhealthy food usually contains a lot of salt therefore salt is bad mmmkay? Researchers didn't lie to us; it was your GP who doesn't have enough time to explain why McDonald's is bad for your already clogged arteries. Instead of going through with you on what to eat and what not to, because it's too difficult for most (my doc said avoid McDonald's and BK so now I just eat triples from Wendy's), they said avoid salt.
This is one of the many examples of why I don't care about consensus opinion. Show us evidence, or go away.
Fair enough. Do you have sufficient expertise that you are able to interpret the evidence? Is the evidence clear? Is the evidence properly gathered and analyzed? Do we have enough evidence to draw firm conclusions or merely enough to nudge the direction of inquiry? Will the patient die before you can get conclusive evidence?
Fact is that the human body is complicated and sometimes a good sounding theory is the best we have to go on. A lot of diagnosis are basically well informed probabilistic guesses because we don't completely understand the underlying disease process. Sometimes you have to act before you can be certain of your case. For instance if you have a bacterial infection it can take days to culture the infectious organism and the patient can die before you get a definitive answer. So the doctor has to take an educated guess before he has the evidence. Sometimes a consensus opinion is the best we can do.
What people miss about consensus opinions is why they matter. What a consensus is NOT useful for is as evidence proving or disproving a theory about physical phenomena. A consensus IS useful for as evidence against the (political) argument that there are substantially conflicting opinions when there in fact are not. A consensus is useful for establishing standard of care. A consensus is (sometimes) useful for protection against legal liability.
The link between salt and blood pressure is pretty clearly not the one your Dr. tells you, and this has been known for a really long time. Even the first study to show the "link" turns out to be bunk science:
http://www.stat.berkeley.edu/~...
More recent meta studies have shown that about as many papers find a positive link as a negative link between blood pressure and salt - yes, eating more salt can lower your blood pressure (or, more likely, it's all just noise). Look it up on Pubmed if you want to read all the details. It's a good skill: you'll quickly learn more than your Dr. does about any topic of real concern to you, unless your Dr. is a specialist or obscenely good at his job.
What's sad is that simple to understand explanations that lead to simple to follow prescriptions (ie eat less salt) tend to stick around way longer than the scientific consensus behind them.
My physiology professor explained it to me years ago. There's two reasons. First, we're told to cut salt not because salt is bad, but because we eat shitty food filled with salt. Telling people to avoid salt is easier than telling them to avoid bad foods.
Yeah, that's what I did. Avoided salt and went for the carbs instead. Now I've both high blood pressure AND am type 2. Worked great. Protein, often high in salt, or carbs. Choose your poison.
Obligatory http://xkcd.com/859/
Yeah, much of what we know is being overturned. Some of the disinformation was probably created by the food companies that wanted to make cheaper food. Back in the 70's we were told that fat was bad, and so all these processed foods got lots of extra sugar instead. Now we find out that sugar is bad and you need to consume more of the right fats. We're also starting to see that this "food pyramid" they taught us about should be basically inverted. The reason for the food pyramid is more to do with cost (grains are cheap) than nutrition.
Today, we know a hell of a lot about the impact of genetics, microbiotic flora, and many other things that affect individuals differently. For instance, many people have some mild sensitivities to various food proteins, although no always enough to notice more than some unexplained lethargy unpredictable times after eating certain foods. Of course, for some people, it's bad, like those with celiac disease.
Here's an interesting one: Apparently, about 10% of the population (US or world, I'm not sure) has a homozygous MTHFR C677T mutation. These people cannot convert folic acid (which is artificial anyway) or folinic acid (found in lots of vegetables) into methylfolate. As a result, these people suffer from massive B9 deficiencies (which indirectly causes others, like trouble absorbing B12). Moreover, it's not just that folic acid and folinic acid are not useful to them; they're functionally poison, interfering with the normal function of the methylation cycle. So these people need to take large quantities of methylfolate and cut out certain "healthy" vegetables. They also have to cut out "enriched" foods. We're starting to see a correlation between health problems increasing in these people and the mid-90's FDA mandate to enrich certain foods with Folic Acid. Lovely.
I would mod you up. I don't see why they can't simply test the hypothesis by feeding some animals or people more salt. Easiest thing to test ever.
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After reading this, I must go and have a bacon and egg sandwich with ketchup...and extra salt
Donte Alistair Anderson Roberts - hi son!
Karma: Chameleon
Even US worker bees that do have a fair amount of vacation time available to them rarely dare take even 5 days at a time off. Why? The not unfounded fear that some bean-counter or your PHB will start thinking, 'hey, maybe we don't need the guy on vacation AT ALL'. So even while on vacay, we sufferers of never-ending Puritanism can't fully relax due to the fear of a pink slip waiting for us in reward for our holiday tan.
Bingo. Processed foods are basically built out of salt and high levels of carbohydrates, which is just a fancy way of saying 'do you want a large order of diabetes with that'?
That's a nice theory, but none of the primary literature I've read on this topic, or review articles, have ever suggested that it was misdirection. Perhaps that's how your prof justified his behavior, but I don't think it is what most Dr's think they are doing.
That "point" you make, though, is essentially an argument from ignorance. "I haven't looked at the evidence, thus it's not true" is a good way to be wrong a lot.
The problem with the science surrounding nutrition is that for a long time the people investigating nutrition were not scientists, and later actual scientists were handicapped by the poor state of the art. So studies would compare diets where one had a higher salt content than the other, but simply put variables were not controlled, and as it turns out the other differences between the samples vastly outweighed the supposed independent variable.
High-salt foods are typically, but not exclusively, unhealthy highly processed foods of poor nutritional value. That is a real statistical correlation even though the salt itself is not the issue.
I got diagnosed with high blood pressure and got the doctor pressure me into starting to use blood pressure meds. I was also cautioned against losing "too much" weight even though I was clearly 17 lbs over the recommended BMI zone. I got a blood pressure monitor and started experimenting. In the end, I found that taking a 45 minute to hour brisk walk, had the most lasting and immediate effect on my blood pressure, even more so than the medication, which I've stopped taking.
Dr. Melik: This morning for breakfast he requested something called "wheat germ, organic honey and tiger's milk."
Dr. Aragon: [chuckling] Oh, yes. Those are the charmed substances that some years ago were thought to contain life-preserving properties.
Dr. Melik: You mean there was no deep fat? No steak or cream pies or ... hot fudge?
Dr. Aragon: Those were thought to be unhealthy ... precisely the opposite of what we now know to be true.
Dr. Melik: Incredible.
http://dowdnotesonnapkins.blog...
You would think sometime in the last few centuries someone would of bothered to get a few people together, control their food intake, adjust salt intake, and see what happened. If we are studying water retention, and its effect it could be a short-term study of around a week.
We know what happens to blood pressure in the short term. Salt affects blood pressure = known fact. We've understood that for a very long time. That is completely different from proving that salt affects heart disease or salt affects mortality in patients with heart conditions. Those things are MUCH harder to test because they require large, long term population studies. They're expensive and difficult studies to do. The problem is that people took the fact that salt affects blood pressure and applied it (without evidence) to treatment of heart disease when there was no known causal link between the two.
This is the logic that was used:
A) We know salt affects blood pressure.
+ B) We know high blood pressure can cause negative patient outcomes in patients with heart problems.
= C) Therefore controlling salt should reduce negative patient outcomes
The problem is that A + B does not equal C. We just assumed that it did because it sounded right. You have two bits of data that seem to add up to a logical result but it turns out that the equation is more complicated and thus our simple "answer" is wrong.
There is not one food that's bad for you, it's bad quantities of food. Hell, you can survive small exposures to highly toxic substances as much as you can have a serving of potato chips from time to time and remain healthy. My BMI is about 33 because I love the quantities.
Chewbacon
The Bible is like Wikipedia: written by a bunch of people and verifiable by questionable sources.
I was being serious, but if you want to think I'm clever, that's OK too.
That has given us margarine (plastic for your body), high carbohydrate diets loaded with wheat gluten, and the result is massive obesity - and all the concomitant health issues.
There is no causal link known between gluten and the obesity epidemic. Gluten sensitivity appear to be merely the latest in a long string of fads jumped on by people who are hypochondriacs as the demand for gluten free products has hugely exceeded known affected population. While there are a relatively small number of people with coeliac disease and other sensitivities, there is no (credible) published evidence that avoiding gluten has any benefit for most people or that it is a primary driver in the current obesity epidemic.
You NEED a good amount of cholesterol for a healthy nervous system, and avoiding eggs and cholesterol containing foods in general is thought to be responsible for the increase in Alzheimer's disease, among other issues.
That is little more than a hypothesis. We do not know with any certainty what causes Alzheimer's disease. Anyone who claims we do is selling something or confused. We are learning lots about it but we do not fully understand the disease process. There may be a correlation regarding eggs and cholesterol but the studies simply haven't been done to establish any sort of causal link in the disease process.
Furthermore you might consider linking to the source material you cite rather than an editorial in a random non-peer reviewed website that refers negatively to statin drugs as "mainstream medicine". That is not what I would consider an unbiased or credible source and it casts your argument in a worse light than it probably deserves.
But it does help with water retention, right? And you would imagine that as the body retained more water it would become generally more pressurised?
That doesn't automatically mean that it affects mortality or patient outcomes. The human body is complicated. Just because it seems logical doesn't mean it actually is a problem.
All we need are dissection records or dissection of well-preserved corpses from the era, so as to examine the state of organs.
The few remaining corpses of people 100+ years dead will most likely not give you the information you seek. There simply is not enough material remaining even among that which is well preserved to make authoritative claims regarding entire populations. At best we might get some hints and get some limited insight but there will be pretty sharp limits on making serious comparisons. Furthermore, I don't know how much time you've spend working with medical records but I've spent a lot of time with them in my professional life. Even modern medical records can be pretty bad. Medical records from 100+ years ago are very difficult to glean useful information from in a lot of cases. Not saying it can't be done but our understanding of medicine has advanced rather a lot since then.
Finding the source material is difficult.
That's putting it mildly. It's an interesting project you propose but you seem to be making it sound much easier than it is. That is a very challenging study.
That is the same as dipping then. The snot in your nose will dissolve the nicotine and then you'll be joining the rest of us smokers in no time. :D
It's not overstated, it's outright bullshit, and always has been.
Sodium does not increase blood pressure, nor does sodium chloride, nor any other common table salt.
People with high blood pressure choose saltier diets. Healthier people, in large part to the widespread publication of the salt = high blood pressure myth, choose less salty diets. It's like using statistics to compare STD rates among circumcised men after decades of telling people to circumcise their kids because it's safer - the health conscious will believe you and get it done, the reckless won't. Those people (and their kids) then continue to engage in health-conscious or reckless behaviors as they normally do.
Someone should tell these deniers we already have a consensus on the effect of salt on blood pressure.
BMI determines my BP. It's like clock work. Higher BMI, higher BP. Anytime I'm over 220, it goes up. Below 220 I'm in the normal range. If I eat something very heavily salty, of course it goes up. Don't eat a salt lick.
When you have High Blood Pressure, you develop High Cholesterol. When you have High Cholesterol, you develop High Blood Pressure. Thus far, the only known way to fight both at once is Fish Oil. Take three 1000mg pills per day (one every 8 hours). It's not a cure, but is sure helps...