>immune signals sent from the gut can compromise the brain’s blood vessels
This is known, Rhonda Patrick talks about it on Joe Rogan (I can hear you groaning).
What confuses me is that this ties new research to old, outdated research (the old wisdom that salt leads to high blood pressure). No sources, but latest studies show excess salt is not harmful in healthy people.
Certainly. The first sentence already instilled a sense of "they're full of it" in me. I know that's biased.
I checked one of the papers they refer to [0] and... well, they fed mice (not humans) a diet with an 8- to 16-fold increase in salt.
As with all nutrients, there is an optimal intake range, and anything below or above that is by definition sub-optimal. In humans, the optimum for sodium intake per day seems to be well above dietary recommendations, but also well below 16 times the amounts described in those recommendations.
Also, it is worth noting that the first sentence in the linked paper is again repeating the same unreasoned "we all know salt is bad" dogma. Diets high in salt in the western world are also high in many, many other things that are bad for you. Epidemiology is useless to derive new information, it only works to establish future work or to deny previous hypotheses.
Across populations the average salt intake is around 3.7 grams of sodium per day.
Sodium intake is actually regulated by the body, just like protein. Your body demands more salt when it needs it. Which means that around 3.7 grams might actually be the optimal amount of sodium intake.
There are many studies showing that the standard recommendation for reducing the salt intake is bullshit. Not only that, but reduced salt intake is linked to obesity and sugar cravings.
Also before refrigerators, like in the 19th century, people consumed a lot more sodium because salt was the primary way to preserve food, especially meat. All modern chronic diseases were rare back then ... and yes, heart disease was harder to diagnose, but improvements in technology can't explain it fully, plus we are also talking of diabetes and cancer.
For skeptics, I recommend reading "The Salt Fix" which provides a good overview of the history and of various studies: http://thesaltfix.com/
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I'm not saying that healthcare professionals are idiots.
The problem is that healthcare is reductionist. Studies that properly use the scientific method don't lie, but the problem is that people often reach the wrong conclusions.
It's like in that fable in which a group of blind people are told to feel and describe an elephant, only in real life some of the blind people have more political clout than others.
Maybe someone thought about it mechanistically in the sense that more sodium in our blood also means more water (to keep both electrolyte balance and dilution in acceptable ranges to sustain life). More water means more blood volume or pressure if volume is limited.
Someone then probably tried to prove this by checking whether dietary salt intake leads to hypertension. However, medical and nutritional science are very limited in the ways they can conduct research. So they probably did an epidemiological study and saw that populations with hypertension also had a high dietary salt intake. Proof! Except... well, no.
Our kidneys are perfectly capable of balancing this out as long as we don't ask too much of them. More salt in your food than you need? More sodium in your pee. Less salt in your food than you need? Well, you're screwed.
Edit: Sorry for being unable to provide a direct answer to your question, but I felt compelled to reply.
Edit 2: After a search in Google Scholar, the earliest study I could find is from 1950 [0]. They studied the link between salt and hypertension in rats by replacing their drinking water with 2% salt solutions and measuring their blood pressure. It seems to me that all non-epidemiological studies are useless extremes... With no "clean" water (all water intake was hypertonic) the kidneys can't really dispose of much.
Edit 3: The actual paper recognises in the discussion (with citations) that it is impossible to cause hypertension in rats without artificially controlling all their water intake. Wow. Even if all water is salted, as long as it's iso- or hypotonic there is no hypertension.
Just an anecdote, from my experience of water-only intermittent fasting for 5 days.
First time I did it, from around day 3, I will start feeling dizzy, if I suddenly standup from either lying down or sitting in a relaxed posture. Later I read that it was caused because of low blood pressure due to no salt intake. The next time I did intermittent fasting, I took some salt with my water, and the dizziness problem was not there.
I read long ago that a famous american cardiologist simply asserted that high salt intake leads to high blood pressure, and that it has been known as a fact since then.
There have been studies showing that, but they've been inconclusive according to the meta reviews.
It's like with cholesterol, i.e. the claim that eating saturated fat can increase LDL particles in your bloodstream (it can), but to jump from there to claiming that increased LDL causes heart disease is a stretch, because LDL is just a transport mechanism and naturally, it depends on what it transports.
People are inclined to search for easy solutions. But unfortunately nothing is easy about our metabolism.
>I checked one of the papers they refer to [0] and... well, they fed mice (not humans) a diet with an 8- to 16-fold increase in salt. As with all nutrients, there is an optimal intake range, and anything below or above that is by definition sub-optimal. In humans, the optimum for sodium intake per day seems to be well above dietary recommendations, but also well below 16 times the amounts described in those recommendations.
Is there some underlying assumption that those researches are idiots and didn't know all that?
The logical interpretation is that they gave 8- to 16-fold increase in salt purposefully, because they cared to see whether there are any specific effects mediated through salt. In over words, they want to put the effects on full blast to magnify responses and be able to see some novel connection, not to see how a mouse cops with mild over-consumption of salt.
Specifically, the article says that they found it resulted "in increased vulnerability of the brain to autoimmunity", which one wouldn't expect from sub-optimal salt intake alone. This is not some rehash of "very high salt = blood pressure, duh!".
Oh, not at all. They are not idiots. That paper was written with a purpose which was properly met (mainly getting to publish and, to a lesser extent, to confirm a previous notion or bias).
The issue is reporting of results to the public. Someone feeds mice a ridiculous amount of salt and notices they have some health issues. Let's assume for an instant that this is somehow useful for some reason (I mean, salt poisoining has been known for millenia and people actually commit suicide by drinking saturated salt solutions). Even in that case, journalists are still distilling the whole thing into "more salt is bad", which is what the average person will understand. The general public doesn't read scientific literature with a critical thinking mindset, if at all.
Mine still tells me I should avoid eggs because they will raise my cholesterol. I wouldn't call him an idiot, just not quite up to date on the latest nutritional studies. Not a big deal since our understanding of nutrition seems really weak and changes pretty often.
Which suggests that salt intake does raise blood pressure slightly, but it's a very small effect and does not measurably impact actual cardiovascular outcomes.
Total tangent, but since our understanding of nutrition is weak and has shifted so much over the decades, why is it not also reasonable to doubt our understanding of Earth's climate and the extent to which CO2 impacts temps?
Not yet mentioned: Collectively, the human gut evolves. Over quite a short timespan! Climate is basically rock solid by comparison.
For example, a new type of food may become quite popular over the course of like five to ten years. In that time millions upon millions of people will undergo a change in their gut flora from eating that food--even if only on occasion!
Who TF knows what the long term impact of such an evolutionary change could be? 90% of the time it's probably nothing but 10% of the people might develop IBS later in life because their gut bacteria suddenly evolved in such a way as to throw off the "balance of power" (as it were... The many zillions of gut bacteria are constantly at war with each other to process food faster and more efficiently).
The climate is a simpler, easier to measure, and easier to experiment on system than the human body. Also there are lots of different bodies which all change over time, but there is only one atmosphere.
The science of climate change is also multi-level, gradually converging on details with more and more sophisticated models, but the core of it rests on the absorbtion and re-emission spectra of CO2 and water vapor, which is some fairly simple long-settled experimental chemistry.
That's easy to answer. The problem with nutrition is not that science does not work. So extrapolating from "it is difficult to study nutrition scientifically" to "it is difficult to study climate change scientifically" is unjustified.
The issue with nutritional science is that you essentially have to rely on humans accurately taking some prescribed action and self-reporting it truthfully. As far as data points go, that is as flimsy as it gets.
Isn't the vast majority of climate change skepticism just political ideology anyway? I really haven't met too many people that were interested in rebutting the science.
I think the answer there is that if you are wrong and crazy to question our current understanding of nutrition, you are probably only hurting yourself and maybe your kids. If you are wrong and crazy about climate change, you are hurting everyone on the planet. And it's a very charged topic because we already have plenty of people who don't want to inconvenience themselves to benefit the climate, so questioning climate change tends to give such people more justification for behavior that is selfish to the point of monstrous already.
I'm an environmental studies major. I think it's complicated. I tend to not bother to argue it. My doubts are not some kind of definitive proof that the assertions of others are wrong. I mostly think it's not worth debating at this point in time.
There are plenty of negative changes that are well documented, such as species going extinct, species on the Endangered Species list, etc. We don't really need to prove global warming one way or the other to know that we need to make some changes in a big way and very soon because the course we are on is clearly a crash course.
>I wouldn't call him an idiot, just not quite up to date on the latest nutritional studies
Since "the latest nutritional studies" are a dime a dozen, and one says one thing, another says the opposite, it's wise to ignore them altogether until they are grown more and established into a concrete set of suggestions.
I'd ignore anything that hasn't reach the level of "nutrition 101" in a university course, and is still on "just published on a peer reviewed journal" level.
The older I get, the more I just settle on nutritional advice that goes something like "the more processed it is, the more likely it's not good for you" and "everything is fine in moderation" and "eat what you want, just eat less".
I've found it is folly to blindly accept doctor's advice, at least for general practitioners. Second opinions and personal research are a must for anything that matters, unless you have been lucky enough to find a good doctor one and are able to stick with them. Respect for the GPs who are capable of saying 'I don't know' or 'I'll need to research this'.
Even specialists disagree, leaving you with the choice of which you trust more. They can't all be right.
> Even specialists disagree, leaving you with the choice of which you trust more. They can't all be right.
That leads to confusion and general mistrust for doctors. If skilled doctor doesn't know what he does, how can I? If I don't know better than doctor, how can I know who gives better advice? How to find that good advice?
I've had enough doctors that my viewpoint is different. They are human and can absolutely be wrong. Challenge them if you don't agree with their recommendation, a good doctor will tell you why they gave the advice, what the probable consequences are for ignoring it, and how confident they are. If your doctor reacts negatively to being challenged, find another.
Look I'm not going to bother defending a doctors point of view, but simply say that within reason seek other professional advice or a different doctor if you have concerns. Though it is concerning that you've just simply brushed off a doctors recommendations so lightly just show me that I'm not going to persuade you either way.
Most doctors know very little about what food does to the body.
If you have a specific medical condition, a best practice is to start a folder of some sort and collect good information there and try to understand it yourself. Another good thing to do is keep a health journal where you track, to some degree or other, specific metrics pertinent to your specific condition.
What I have concluded is that a lot of advice of that sort is over-simplifying a complex biological process. Figuring out what makes sense in terms of diet involves fleshing out your own mental models for the pathology of the condition in question.
> Most doctors know very little about what food does to the body.
This is bullshit. "Most doctors" know very little about the electromechanical processes involved in a keystroke but they still know it results in a letter appearing on the screen.
A doctor's job is to keep you alive and to a lesser extent, healthy. They are not in the fitness businesses but they sure know that fit people have less health problems. Problems that they ultimately get stuck treating.
Do they know the chemical processes at work (in detail) in the brain when you eat something? Probably not... Not unless they're a gastroenterologist/neurologist. But do they know that eating loads of sugar every day can lead to Type II diabetes? They sure do! I'd even go so far as to say, "Doctors know quite a lot more than most people" about such things!
They also know loads of things about salt! Ask any psychiatrist about the effects of high salt intake on various mental conditions (and their respective treatments). Ask any pediatrician what would happen if you fed a tablespoon of salt to a baby. Ask a dermatologist about salt in general (wow, take a seat and be prepared for a lecture).
This comment is strangely defensive (are you a doctor?). I’ve had to deal with all kinds of issues over past decades and the “doctors know little about food” hypothesis is 100% true in my case. Without getting into too much detail looking back over past dozen doctors or so maybe 1 focused on factors related to nutritional effects for causes/cures of conditions i was dealing with. And knowing what i know now, nutrition was more effective in treatment/prevention than anything they prescribed. It almost seems to me like they follow a manual that treats symptoms and when-in-doubt-do-surgery type solutions.
Most doctors recommend changing diet to aleviate symptoms. Its just that most people don't do it.
When you say "nutrition was more effective in treatment/prevention than anything prescribed and stating 1 focused on that" I call bullshit. Its just a known fact that diet changes can alleviate issues so its pretty much a given but its not going to alleviate the issues right away (in most instances) which is the doctors primary concern. So they often prescribed medicine to do just this.
If you need a doctor to explicitly mention to you that good nutrition will improve your health, then I'd suggest being a little more perceptive. But case in point, every doctor I've met has recommended diet changes to alleviate my symptoms.
> If you need a doctor to explicitly mention to you that good nutrition will improve your health, then I'd suggest being a little more perceptive
huh? the point was made about their in depth understanding of impact of specific nutrition. not that "good diet is important" generality. and I am being "a little more perceptive" by doing a decade of my own research. not sure why that comment was necessary or what it has to do with my point
By good diet, I mean higher intake in fruits and vegetables, moderate intake in meats. Stay away from high processed foods with excessive sugar, fat, and sodium. It shouldn't take a decade of research to figure that out unless your diet is completely strict due to specific ailments.
By good diet, I mean higher intake in fruits and vegetables, moderate intake in meats.
this is a common truism that may or may not be beneficial to any one individual. it has nothing to do with understanding of nutrition as pertaining to treating specific health issues.
it's like saying, "exercise and sleep good". while this is true in most cases, has nothing to do with original point "Most doctors know very little about what food does to the body."
No, but what's good for the gander is usually good for the goose (I know its a rephrasing of the original). That's how we get effective medicine and built models of understanding. While individual factors are prevalent, they usually don't cause as much deviation from the overarching model. For example, higher intake in fruits and vegetables is a practical step, easily understood, and well studied to help reduce meat related illnesses like heart disease and CVD. While the mechanisms aren't well understood, that doesn't preclude the data.
> "A doctor's job is to keep you alive and to a lesser extent, healthy. They are not in the fitness businesses but they sure know that fit people have less health problems. Problems that they ultimately get stuck treating."
But doctors don't get "stuck" treating health issues! On the contrary, that's how they get paid! Doctors' jobs, unfortunately, have perverse compensation structures which disincentivize their helping patients reach maximum healthiness. They get paid to keep you alive, yes. But they get paid much more if you remain in a state of imperfect health -- and thus remain a patient, requiring paid treatment -- than if you happily stay fit and only visit for routine checkups.
Some cultures (eg the proverbial village doctor in some parts of Asia) resolved this conflict of interest by having members of the community pay the doctor only while they're healthy, but pay nothing when faced with illness. Interesting to think what such a model might look like in modern western civ.
I'm not going to get into the back and forth below this comment.
I have a form of cystic fibrosis. It is standard practice for CF clinics to have a dietitian on staff. Last I checked, they recommended a "high fat, high calorie, high salt" diet for CF. In line with that, they straight up recommend you eat junk food.
I'm currently drug free, which is supposed to be impossible. I achieved that in part by focusing on improving my nutritional status. Instead of eating a high calorie, junk food diet, I got very picky about food quality and nutritional value.
So that's where I'm coming from. I'm a former homemaker. If me reading up a bit on nutrition and food chemistry and applying it to my life can get such dramatically better results than conventional wisdom for my condition, it seems to me the bar for what doctors need to know about food and health is set pretty low.
My experience has been roughly in line but I usually find they're somewhat knowledgeable. Just remember they're stuck with recommending guidelines or else so they haven't got much room to move when the guidelines are a total farse.
An idiot would be a person taking seriously nutritional advice from a doctor that spent a grand total of ~5 days learning about the subject in medical school.
I always understood the salt issue as a public health suggestion. EG if 1 person in a hundred has salt-sensitive hypertension, telling everyone to lower their salt intake will help that 1% of the population. The other 99% are just inconvenienced.
Obviously, they could tell people that this is the reason and treat us like adults, but they don't seem to want to.
I find I consume more salt at times after intensive sport (semi-marathons, swimming). It looks my body naturally requires more salt to restore itself. So the advice to consume less salt should not be generalized.
The question is whether salt (sodium chloride) is exactly what your body needs... or just the best it knows it can get.
Perhaps magnesium would be better, but sodium chloride can also do the job at the cost of some side effects. And if salt is all you have tried, then your body will signal that it needs salt, because that's what worked in the past.
Cravings. Also, if you put salt in your mouth and it tastes good, you need sodium. If you can't stand the taste or it tastes "chemical", then you don't need it as much.
It's strongly hypothesised [1] and currently a very active research question that gut microbes are able to send signals to your brain to influence your "cravings". If that should be the case, listening to your cravings wouldn't be what your body naturally requires or what's healthy for your.
I didn't say anything that would imply that. However, if gut microbes, who act in their self interest, do cause cravings, then cravings cannot be used to determine what your body needs.
There is a significant difference between the following two statements:
1) Cravings cannot be used to determine what your body needs with 100% accuracy because some of them might be caused by gut microbes.
2) Cravings should still be taken into account because most probably only a small percentage will come from cravings.
I understood you were referring to the first in your previous comment, so apologies if that was not the case.
Either way, the only research that I know of pertaining to this topic is that some yeast (IIRC candida) can trigger carbohydrate cravings. That is something you should probably never listen to, even if they are physiological. Note that I have a strong bias here as I adhere to a no-fiber ketogenic diet.
The gut brain axis is a new and exciting field of research. Here's an educational animation showing the pathways that make these connections possible: http://mmm.hsiao.science
Yes. The traditional Indian medicinal system called Ayurveda (as well as traditional Indian culture in general) regarded food as a form of medicine. Every form of food could potentially affect your body in various ways and many disorders and diseases were treated by either modifying the diet or by special herbal concoctions (as the concept of synthetic, molecular medicine wasn't discovered back then)... it makes sense for preventing many lifestyle related problems.
The Welness Sense ... combines the yogic view of food as sattvic, rajasic and tamasic with Ayurvedic perspective and further relates it to the modern view of foods as acidic and alkaline. This is also the first time that Ayurvedic prakriti (vata, pitta and kapha) has been discussed in the context of yogic prakriti (sattvic, rajasic and tamasic) in a truly cohesive fashion. The Wellness Sense extracts the essence of Ayurveda, yoga and tantra to combine it with modern medicine in this simple, step-by-step handbook on how to take better care of yourself. Accessibly written, deeply researched and distilled from Om Swami’s own lived experience, The Wellness Sense puts your health and happiness in your hands.
If your doctor tells you to do 10 things, where 1 of them is the right move, 1 of them is dangerous, and 8 of them are placebos... then you don't really have a doctor.
Quite possibly ... not too long ago, knowing what you could and couldn't eat and the effects were surely part of oral tradition.
E.G. US natives knowledge of the pain-killing effects of 'something' in birchbark existed long before Bayer synthesized the same chemical in the late 1800s.
Willow, and yes birch ('canoe birch' = white). Each is probably preferred where it's more common. Fur trappers knew about birch where willow was rare, and BTW long before Herr Bayer was born.
sample of one. Lactulose breath test confirmed SIBO with pretty high levels of both - hydrogen(78) and methane(29).
Antibiotics didn't really work and resulted just in a minor improvement (depending on study, the antibiotics work in 30%-70% cases). The GE was very reluctant to prescribe even the second antibiotic, and lectured me on very low chances for success in the long term anyway as the issue tends to return soon even when antibiotics work ("we can't give you antibiotic every month, cant we?"). When the 2nd didn't work too, i didn't see a chance to make him prescribe the 3rd. So i went with traditional methods and medicines (interesting that the traditional way in addition to addressing direct manifestation - ie. bacterial overgrowth in this case - also focuses on root causes which wasn't the case with the GE). That worked (slowly, took few months), and the maintenance mode is far cry from the supposed monthly or whatever periodic begging of the GE for antibiotic (i didn't like his approach, yet i understand that being board certified he most probably has very good reason for his position/approach as, in particular, frequent use of antibiotics is known to be not a good thing).
(IANAMD, and not promoting any method/supplement, just sharing my personal experience and thoughts/speculations) Started with salt flushes (osmotic laxative action to weaken/break/wash away the biofilms as antibiotic studies, in particular for SIBO, frequently hypothesize that bacteria organizing into biofilm is a reason for the antibiotic inefficiency) almost daily at the beginning tapered down to once per 2-3 weeks currently plus the oregano oil, artemisia extract, berberine, garlic (fresh when i can and tablets when i cant) and HCL supplementation (each of this alone i tried over the years and they all had shown noticeable improvements, while taken together they produced much stronger effect for me - not surprising given our current knowledge of multi-species bacteria colonies like the one in SIBO)
The discussion on this piece is quite alarming. From general distrust of doctors, to thinking people can research themselves into knowing better, to slights about animal studies not being effective arbiters to humans.
No wonder there's so much BS in the medical industry. Too many non-doctors with an opinion.
Anecdotal thought: I have noticed that I feel angry after eating bread. Sounds goofy, but I realized that it wasn't the caffeine from coffee and it wasn't me "not being a morning person". Recognizing this has helped my relationships a surprising amount.
I have a problem with bread too, I start falling asleep for like 5-10 minutes. I think it's either gluten sensitivity or carbs to blame. I try to avoid bread because of this.
So, a few thoughts from a person with a condition that significantly impacts how my body processes salt:
1. After years of pursuing diet and lifestyle approaches to managing my condition and reading up on health stuff generally (and talking to people with PhDs in topics like Chemistry and Biology), I concluded that the circulatory system is the means by which all of the body interacts with all other parts of the body. So if one thing is out of whack in one part of the body, the primary way it impacts some other part of the body is by way of how it impacts blood health. At this point, I think this should be viewed as a kind of "Biology 101" thing and I'm not very impressed with dramatic pronouncements that the gut impacts blood vessel health in the brain, le gasp. To me, that's kind of "Well, duh!"
2. The body uses various molecules in conjunction with various others, so one of the things you see is that adding more of X by itself will naturally cause chemical derangement. Salt in particular works in conjunction with a number of other minerals and the natural source of salt -- the sea -- contains a variety of other minerals. "Table salt" is not how nature supplies us with salt. It is, itself, chemically deranged from the get go and very much on purpose.
One of the things they put in table salt is a chemical to make it pour easier. We assume this chemical is harmless, but I'm not aware of any actual studies on what it does to the body, especially not if you start consuming a lot more of it than "normal". So if you are consuming a lot of table salt, you are likely consuming other things that aren't normal while not getting the variety of minerals found in ocean water. I found high quality sea salts that had that variety of minerals to be highly helpful in regulating my body's relationship to salt. Getting more salt helped me, but only if it was accompanied by the right minerals, the right carbs and the right fats. It took some experimenting to find the right combo.
3. About 70 to 80 percent of the immune cells in the body are found in the gut. So, your gut is a primary part of your immune function. It really should be no surprise at all that what you eat impacts immune function.
4. I found it enormously helpful to read up on Altitude Sickness. This was a huge Aha! moment for me that makes it clear how the blood connects different organs.
You begin peeing at altitude well before you are at any risk of suffering Altitude Sickness because the thin air means you can't breathe out as much blood gas wastes as you normally would, so your body starts shunting the excess blood gas wastes through the kidneys to get rid of them. This has other consequences, such as dragging salt and other electrolytes out with it. So you need not only more fluids at altitude, but also more electrolytes as well. Heat waves above 105F and hiking at altitude are about the only time I consume Gatorade.
> We assume this [anti-caking] chemical is harmless, but I'm not aware of any actual studies on what it does to the body, especially not if you start consuming a lot more of it than "normal".
In Europe, thankfully, it's Sodium Ferrocyanide[1] which has been studied[2][3].
"The Panel concluded that ferrocyanides (E 535–538) are of no safety concern at the current authorised use and use levels."
> The ferrocyanides are less toxic than many salts of cyanide, because they tend not to release free cyanide. However, like all ferrocyanide salt solutions, addition of an acid can result in the production of hydrogen cyanide gas, which is toxic.
I'm assuming (maybe wrongly) that if stomach acid was capable of triggering the production of hydrogen cyanide gas, those two linked reports which say "perfectly safe for humans" would say "DO NOT EAT THIS BLOODY HELL WHAT ARE YOU THINKING" instead.
Not for cyanide. It occurs in nature far to frequently for us not to be well suited to clear it. Our bodies even convert it to B12 in some cases. A hand full of nuts (organic, free-range, et al) will likely have more hydrogen cyanide than the anti-caking agent in table salt.
This is known, Rhonda Patrick talks about it on Joe Rogan (I can hear you groaning).
What confuses me is that this ties new research to old, outdated research (the old wisdom that salt leads to high blood pressure). No sources, but latest studies show excess salt is not harmful in healthy people.