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More Dietary Salt Increases Urea Synthesis And Energy Requirements

  1. The salt recommendations mentioned by Peat in some of his articles have been the source of much controversy. He has given accounts of people with various conditions recovering when they increased their salt intake to 1-2 tablespoons daily. I also posted studies showing that when sodium intake is below 5g (equivalent to about 1 tbsp salt) daily serotonin starts to rise and the renin-angiotensin system goes into overdrive, combined with increased catecholamines.
    It is considered "common knowledge" across the blogopshere and even mainstream medical practice that increased salt intake increases thirst, and consequently fluid intake, while at the same time reducing fluid excretion. It is the combination of increase fluid intake and decreased excretion that is given as explanation by doctors as to why eating more salt will increase blood pressure.
    This study decided to test the effects of various amounts of extra salt added to the diet of humans. The different amounts of extra salt tested were 6g, 9g, and 12g daily. What the study found was quite counterintuitive. Increasing salt intake led to decreased thirst and increased urine volume. Reducing salt intake generally had the opposite effects. What increased salt intake also did was increase urea synthesis and it was this increase in urea synthesis that allowed the kidneys to form urine saturated with sodium so that the extra sodium can get excreted. However, because synthesizing urea is such an energetically expensive process, increased salt intake indirectly increased energy requirements and thus made people hungrier as opposed to thirstier. Finally, the higher the salt intake, the lower the aldosterone release was in humans, exactly as Peat wrote. However, the higher the salt intake the higher the glucocorticoid release was in those same subjects. I think the increase in urea and energy requirements (metabolism) would be solid reasons to increase salt intake as per Peat's recommendations. However, the high cortisol release is potentially bothersome and may explain some negative effects of higher salt intake in sick people, as @burtlancast mentioned a few times.

    JCI - Increased salt consumption induces body water conservation and decreases fluid intake
    Mission Control for the body's salt and water supplies

    "...The results confirmed that eating more salt led to a higher salt content in urine - no surprise there. Nor was there any surprise in a correlation between amounts of salt and overall quantity of urine. But the increase wasn't due to more drinking - in fact, a salty diet caused the subjects to drink less. Salt was triggering a mechanism to conserve water in the kidneys. Before the study, the prevailing hypothesis had been that the charged sodium and chloride ions in salt grabbed onto water molecules and dragged them into the urine. The new results showed something different: salt stayed in the urine, while water moved back into the kidney and body. This was completely puzzling to Prof. Jens Titze, MD of the University of Erlangen and Vanderbilt University Medical Center and his colleagues. "What alternative driving force could make water move back?" Titze asked.

    "...Experiments in mice hinted that urea might be involved. This substance is formed in muscles and the liver as a way of shedding nitrogen. In mice, urea was accumulating in the kidney, where it counteracts the water-drawing force of sodium and chloride. But synthesizing urea takes a lot of energy, which explains why mice on a high-salt diet were eating more. Higher salt didn't increase their thirst, but it did make them hungrier. Also the human "cosmonauts" receiving a salty diet complained about being hungry. The project revises scientists' view of the function of urea in our bodies. "It's not solely a waste product, as has been assumed," Prof. Friedrich C. Luft, MD of the Charité and MDC says. "Instead, it turns out to be a very important osmolyte - a compound that binds to water and helps transport it. Its function is to keep water in when our bodies get rid of salt. Nature has apparently found a way to conserve water that would otherwise be carried away into the urine by salt."
  2. @haidut

    In the Ray Peat Wiki (currently receiving an error message, so I can't find exact quote) he mentions that large doses of Salt can sometimes damage the stomach lining.

    Wonder if this is a situation (much like Aspirin) where it might need to be dissolved in liquid for easier digestion.


  3. So is Ray using "appetite" in place of "taste" here, or does he mean something else?

  4. Thank you for reporting, I will get that fixed up. :hattip
  5. Just like calcium: phosphorus ratio and calcium:magnesium ration, is there such a thing called sodium : potassium ratio ? Will the requirements for potassium rise as one eats more salt ? ( I know its very reductionist but could the hunger be an increased need for K not for other macros/micros ) ?
  6. Hmm. Interesting. I never really crave salt :( but i have symptoms that are associated with getting to little so its strange,
  7. It's very difficult to have potassium deficiency as the body has strong affinity for it and absorbs it like crazy from every food that contains it, if the organism perceives a deficiency. Potassium and magnesium are intracellular minerals. Magnesium can be easily lost when ATP synthesis is low but potassium is not easily lost unless there is cell damage and then it spills in the blood. Even a suboptimal potassium intake does not tend to create deficiency as long as there is no tissue damage like over-exercising or severe hypothyroidism that can cause rhabdo. But trying to eat potassium rich foods like OJ, potatoes and even ripe/cooked bananas should address any deficiency concerns. I don't think there is a sodium : potassium ratio to be striving for.
  8. if high salt increases the energy requirements

    could this lead to low blood sugar and consequently to higher cortisol?
  9. I think Peat mentioned (in the KMUD interview) that Urea itself was a metabolic stimulant, and that urea applied to wounds could make them heal faster, and without scarring. It also works great as a skin moisturizer, if used topically.
  10. I've heard anecdotal stories that people on low salt diets lose the taste for it, even if they are lacking it. You could try salt or electrolyte tablets, they are sold at places like Walgreens, Sporting Goods stores, and Amazon. Oddly, I never seen them at places like GNC or Vitamin Shoppe.

  11. I cannot find my original source but I remember the issue with both aspirin and salt was in the form of a tablet/capsule.
    Dispersed as powder/granular was much less or not an issue
    Mixed with foods/liquids was a non issue
    I will keep looking for it.

    This is why the idea of salt tablets/capsules is no bueno
  12. That's certainly a possibility. Another one is that aldosterone and cortisol may have an inverse relationship since they both bind to the same "receptors" and when aldosterone is lowered by the high salt then cortisol rises to compensate. But I like the energetic deficit explanation more.
  13. That's true. Salt is also a direct metabolic stimulator itself. I think it increases the breakdown of ATP, which the cell takes as a message to produce a lot more as a response.
  14. It sounds like pannacotta would be a great staple.
    Thanks for sharing this research.
  15. Oh yeah! I eat it every time I go to an "Italian" restaurant around here. Even the fake ones have it on the menu. It probably has carageenan but I just don't care as it tastes so good.
  16. I can “confirm” the anecdotes that some people accustomed to low salt diets or some with hypothyroid states lose appetite for salt. Other hypothyroid people crave salt and seem to partially self-treat by increasing salt intake.

    Habit seems to be part of it. In some cases, when the person is willing to increase salt intake, the appetite for salt also returns. Improvement of symptoms with adequate salt intake also reinforces the increased appetite for salt.
  17. Does Peat distinguish different kinds of salt? Dr. Buteyko was big on unrefined (grey) sea salt. It contains 85 minerals in the same proportions found in the human body. He found that over-the-counter mineral supplements tend not to be absorbed by the body but minerals from sea salt do. Unrefined sea salt is also delicious. During my Buteyko teacher training we drank 'salt tea'. I thought it would be horrible. It was delicious. I encourage all my clients to throw out their table salt and get some of the good stuff.
  18. I posted this is a different thread:
    I was curious what Peat thought and emailed him the study. He didn't have a ton to say:

    I saw this study and wondered your opinion:

    JCI - Increased salt consumption induces body water conservation and decreases fluid intake

    They seem to be saying that increased salt intake would increase cortisol levels to break down fat and tissues for water, contrary to their belief that water intake was the main mechanism to maintain water balance.

    Would love to hear your opinion

    Thanks for the article link, it would be interesting to have more metabolic information about them during the salt changes.
  19. Ray recommends clean white salt. No iodine. So the old fashioned table salt is fine as long as there is no iodine. Sea salt if it is white and non-iodized works well too.
  20. Please excuse my not understanding this but are the studies saying salt isnt good or too much too little isn't good. Can you explain this in layman terms. also what is urea. Thank you.
  21. I posted that quote in reply to the note that the email-wiki was not available at that time. I have not really read the studies.

    Only screened the first one: It says that aldosterone and insulin went down with higher salt intakes. Norepinephrine (noradrenalin) increased with sodium infusion, but decreased on a high-salt diet.

    Free fatty acids were on average higher with high sodium intakes, but they said this was 'not all statistically significant'.
    Lowered aldosterone is a good thing. Increased FFA is not desirable. Both high aldosterone and high FFA impair glucose handling. For me the question is, why did sodium increase FFA in some participants and not in others?

    The authors discussed this question, but did not really come up with a definite answer. If I should guess, I would say that ones with increased FFA had lower liver glycogen stores (blood samples were taken in overnight fasted subject, even saline infusion was given to fasted subjects).

    Urea is formed in the body, for example to detoxify ammonia.

    Urea - Wikipedia
  22. oooooh okay.. got it. Thank you very much. I guess just go by what your body is craving IMO. Don,t overdue salt but make sure you have enough..hmmm. I think you said that somewhere.
  23. Because the extra salt increased metabolic requirements as the study itself said. The people on high salt diet were always hungry. So, even with good glycogen stores you can get into a fuel deficiency state depending on just how much salt revved up metabolism. Thyroid can do the same, as we all know, when consumed on empty stomach or by a malnourished person.
  24. That sounds like if you are obviously hungry and continue to eat while glycogen stores are good that would have you burn muscle and put on weight? Just how my non scientific mind is thinking. Lol
  25. No, because the extra energy you consumes will go into synthesizing urea.
  26. Really. . Wow.. I was so off. Okay this is interesting. Thank yooooooou.
  27. That's what the whole study was about - extra salt increases urea synthesis, which is an energetically demanding process, hence the increase in caloric demands. It's even in the title.
  28. I see it said that but didn't understand what it all ment. I wasn't sure if it was a good or bad thing. Giraffe explained it to some degree and you finished it. It was just very scientific reading.
    like what Giraffe explained above. I wasn't sure what ffa and aldosterone, and if the effects were good or bad. Also he explained urea which I still reading about. I thank you both for your patience of explanation.
  29. will supplementing orally with urea decrease metabolism since the body doesn't have to expend the energy to produce it? what effect will urea supplement have on body temperature? will it increase body temp if the temp was a little low?
  30. Herb Doctors: Continuing Research On Urea

    On urea, but you would expect the same therapeutic effect from more salt:
    "[..]And to keep [the cell] towards the slightly acidic, metabolizing state, in which it doesn’t tend to proliferate; a relatively slightly dehydrating effect."

    But once they're too de-energized, extra salt can be harmful:
    "If the cell is disturbed, then it shifts and loses potassium and takes up calcium and sodium. This is what Gilbert Ling has devoted his life to for the last 60 some years."

    I believe the amounts of salt that optimize health are a bit higher for humans in relation to other animals because we're under chronic stress. No other animal has to endure the task of comprehending Travis' posts.
  31. I want to know this too.
  32. LOL
  33. Aldousteroned?

  34. This has been my experience when I took 2 Tb+ of salt.
  35. This illustrates the anti-cancer effects of urea, which robs tumor areas of their water, which Gar Hildenbrand explained is what paralyses normal metabolism around tumors, and which the Gerson people resolve by restricting salt
  36. I think this matches well with the overall observation from Ling, Warburg, Pauling, Peat, etc that cells start to proliferate when they take up water. So, as per Peat's quote, keeping organism in a slightly dehydrated state should be potently anti-proliferative. In my experience, extra sugar causes this dehydration quite easily confirmed by strongly increased thirst in doses of 40g-50g or more per sitting.
  37. @haidut between burtlancast's comments on salt and tumor growth and your quote above, I'm now a little weary about my salt intake. I've searched to see if Dr. Peat has followed up on these discussions about the possible negatives of salt intake, but haven't found anything. I'm consuming 10 grams of salt daily due to Dr. Peats recommendations - am I potentially harming myself? Any expert advice would be appreciated?

    I was really excited about increasing my salt intake, too, as Dr. Peat seemed so sure about it!
  38. I don't think 10g is that much. Up until the early 1960s the average salt intake for an adult in the US was about 12g-15g daily. These days, with everything being made "low sodium" by default, those 10g probably bring you closer to normality and not anywhere in danger-zone. But I think salt should be eaten to taste, not so much based on set daily goals.
  39. Should not high salt intake be a good treatment for gout? And the gout epidemic a result of salt restriction while still having high protein intake?
  40. Matt stone writes a little on this and unfortunately I don’t have any scientific studies to back up, all just conjecture, but how about adjusting salt intake relative to urine frequency?

    On a high liquid peat diet, which is apparently most optimal due to the intake of primarily sugar as fuel accompanied with the minerals found in milk + oj, I find that I pee... a lot. I know this can’t be good, and I’ll often also start feeling weak and sometimes nauseous or have gastrointestinal distress.

    However, by correspondingly eating very salty foods, such as heavily salting meat and veggies, I find I feel much better. The more OJ I drink the clearer and more frequent my urine, so I think something is very off with my body’s ability to regulate sodium.

    I don’t think it’s smart to hit a set salt goal per se, but go based on how frequently urination occurs, the color of urine, and overall body sentiment. I think the more spaced the urination events (every 2-3 hours or so) and the darker the urine (to an extent) the better.

    Consuming sugar with salt I think might be the winner here. You get the lower aldosterone, increased energy needs, and then the sugar blunts the corresponding rise in cortisol. I know for me, when I have a heavily salted meal with eggs, cheese, veggies, and salsa, and then chase with OJ, my brain starts to tingle, as if everything “right” is occurring metabolically.
  41. Thank you so much for your response and for your help. I will apply your insight and eat salt to taste. Knowing that 10 grams is fine is important for me because this way I have an upper limit in mind while salting to taste.
  42. Of note to this thread, Ray Peat cited the following study in the article Salt, energy, metabolic rate, and longevity.

    The study is https://www.sciencedirect.com/science/article/pii/S0939475305001705

    Design and methods
    Rats were fed a low (LSD), normal (NSD), or high (HSD) salt diet. In a first set, body weight, tail-cuff blood pressure, fasting plasma thyroid-stimulating hormone, triiodothyronine, l-thyroxine, glucose, insulin, and angiotensin II were measured. Angiotensin II content was determined in white and brown adipose tissues. Uncoupling protein 1 expression was measured in brown adipose tissue. In a second set, body weight, food intake, energy balance, and plasma leptin were determined. In a third set of rats, motor activity and body weight were evaluated.

    Blood pressure increased on HSD. Body weight was similar among groups at weaning, but during adulthood it was lower on HSD and higher on LSD. Food intake, l-thyroxine concentration, uncoupling protein 1 expression and energy expenditure were higher in HSD rats, while non-fasting leptin concentration was lower in these groups compared to NSD and LSD animals. Plasma thyroid-stimulating hormone decreased on both HSD and LSD while plasma glucose and insulin were elevated only on LSD. A decrease in plasma angiotensin II was observed in HSD rats. On LSD, an increase in brown adipose tissue angiotensin II content was associated to decreased uncoupling protein 1 expression and energy expenditure. In this group, a low angiotensin II content in white adipose tissue was also found. Motor activity was not influenced by the dietary salt content.
  43. Thanks @tankasnowgod

    People wanting to lose weight might want to increase salt intake.
  44. In regards to the potential cortisol issue, I found this study on Salt Loading that measured both plasma cortisol and urine cortisol metabolites during a week of higher salt loading, in both normal and salt sensitive individuals- Salt Loading Affects Cortisol Metabolism in Normotensive Subjects: Relationships with Salt Sensitivity

    It seems this study found that plasma cortisol was lowered in normal individuals. The higher amount of urinary cortisol metabolites would be the body eliminating excess cortisol-

    " This study clearly demonstrates changes in cortisol metabolism in response to dietary sodium in normotensive subjects. Interestingly, the sum of urinary cortisol metabolites, which can be considered as an estimate of cortisol elimination, was on average increased in sr, but decreased in ss subjects after salt loading. Likewise, the excretion of UFF, UFE, and each of the individual cortisol metabolites (THF, allo-THF, and THE) was higher after salt loading in sr subjects but was unaltered or lower in ss subjects. Of note, these changes in cortisol metabolite excretion after salt loading were accompanied by a decrease in plasma cortisol concentration, particularly in sr individuals. Taken together, it can be envisaged from these data that salt loading induces an increase in cortisol elimination and hence a decrease in circulating cortisol in sr subjects, whereas these effects of salt loading on cortisol metabolism are blunted in ss individuals."

    "In agreement with a primary enhancing effect of sodium loading on cortisol elimination, the changes in plasma cortisol were negatively correlated with the changes in urinary cortisol metabolite excretion in the whole group. In ss subjects, the change in plasma cortisol was not significant, whereas urinary cortisol metabolite excretion tended to decrease. In this respect, the aforementioned inverse relationship between the sum of cortisol metabolites and the percentage change in plasma cortisol is of relevance. It suggests that the reciprocal relationship between changes in urinary cortisol metabolite excretion and plasma cortisol can be regarded as a continuum rather than as a qualitatively different response to salt loading in ss subjects."

    So it seems that in most individuals, increased salt intake would tend to lower plasma cortisol. Caution might be warranted in individuals with known salt sensitivities, and also to be sure to be getting enough sugar to meet increased metabolic demands when consuming extra salt.

    As you can see from the study, plasma aldosterone was absolutely crushed in both groups after one week of salt loading.
  45. Thanks. That last part about lower aldosterone should be rubbed into the faces of ALL cardiologists who relentlessly prescribe salt restriction for people with heart problems, and in more severe cases even dole out aldosterone antagonists like spironolactone.
    Spironolactone - Wikipedia

    All this fraud and money wasted on drugs when the solution is simply...eat more salt (to taste).
  46. A 3 page thread about salt and ive need seen magnesium mentioned. To my knowlegde electrolyte balance is the key, but also kinda tricky. Salt and potassium is what fuel the adrenals and the sodium to magnesium ratio is regulates the Na/K pump.
  47. Not much to say about it, nor is it that tricky. High aldosterone levels will encourage the excretion of magnesium, so the body can preserve sodium. Eating more salt will lower aldosterone levels, which lead to improved magnesium retention. If you want to improve Mag levels, you can either supplement directly and/or start eating more salt.
  48. So since I have some massive bloating going on, I guess that means I need to push my salt intake ever higher?
  49. @Cirion Hmm, I too been dealing with chronic bloating past 2 years.
    Since peating, it has reduced.
    Gonna up my salt intake.
    On Carnivore, I was intaking up to 8g of Sodium / day.

  50. The Aldosterone lowering effect of Salt is a illusionary one.
    Aldosterone amount in blood decreases,hence lowerered Aldosterone-levels.
    But sensitivity increases,and and it increases above the threshold that they deemed normal and viable compared to baseline for their study.
    Normal to High Sodium increases true Aldosterone activity potently,with all side effects.
  51. I've seen nothing to support this claim. Sure sounds like one of those "Rube Goldberg" claims to justify a failing hypothesis.
  52. One high-impact cause of higher Aldosterone is also metabolic acidosis,Chlorine component of salt can effect this.

  53. Anti-Peat - High-Salt Augments Aldosterone Toxicity Despite Lowered Plasma-Readings

    High-Salt Augments Aldosterone Toxicity Despite Lowered Plasma-Readings

    Effect of aldosterone and mineralocorticoid receptor blockade on vascular inflammation
    Hylton V Joffe, Gail K Adler
    Heart failure reviews 10 (1), 31-37, 2005
    Aldosterone, the final product of the renin-angiotensin-aldosterone system, is classically viewed as a regulator of renal sodium and potassium handling, blood volume, and blood pressure. Recent studies suggest that aldosterone can cause microvascular damage, vascular inflammation, oxidative stress and endothelial dysfunction. In animal models, aldosterone-mediated vascular injury in the brain, heart, and kidneys leads to stroke, myocardial injury, and proteinuria. These effects may be modified by dietary salt intake; aldosterone-mediated vascular damage is increased in susceptible animals fed a high-salt diet compared to a low-salt diet despite lower plasma aldosterone levels on the high-salt diet. In humans, there is a growing literature supporting the adverse effects of aldosterone in heart failure, hypertension, left ventricular hypertrophy, and renal disease. Aldosterone receptor antagonists are beneficial even in patients on angiotensin converting enzyme inhibitors and attenuate aldosterone-mediated vascular injury by mechanisms that appear to be independent of changes in systolic blood pressure. This review focuses on the adverse effects of aldosterone on the vascular system and describes our current understanding of the underlying mechanisms for this injury.

    also "haha" at rube goldberg.he is a genuine guy,and a creative thinker.
  54. what does "in susceptible animals" mean?
  55. A single sentence in the abstract of a meta-analysis is hardly proof of anything, especially when that sentence is qualified to "susceptible animals." Did you track down the full text of the study to which this is referring to?
  56. In susceptible Animals means that the conductors made the rodent hypertensive to study effects
    of Aldosterone Levels along this model of hypertension.

    "It is currently
    unknown whether there are additional direct
    effects of aldosterone on target organs. The
    primary insult caused by aldosterone in susceptible
    individuals and animals
    has not been identified,
    and the mechanism by which high salt
    intake contributes to this injury is unknown
    Furthermore, the relative importance of circulating
    aldosterone levels, local cardiovascular aldosterone
    production, and aldosterone uptake from
    the circulation remains to be determined."

    They havent figured it out how this part of the system operates,but they recognize that High-Salt amplifies damage
    mediated by Aldosterone,despite lowered readings of blood-level.An important finding,in that low Aldosterone
    blood-lvl-readings arent indicative of true ,low-Aldosterone-activity,but to the contrary.If we base future risks
    on bloodwork,it means there is a high possibility for a wrong outcome if,in this case,low lvl does not mean low lvl,
    but in vivo high lvl-activity.
    If im feeling calm,secure and sedated with my low,Hi-Salt induced Aldosterone machine-printout,
    and this thing is actually up-side-down,i have to adapt to reach a favorable outcome.
  57. Furthermore,the study was a review of the available literature,the uncontrolled for,population-based
    meta-analyses are a problem,there we are on the same page,but for an author of an review of controlled models
    it is just like using his footnotes,like anyone else imo.
  58. Oh, so in other words, they decided that high salt intake was a problem, despite no evidence, and now they are trying to prove it. I'm still not buying it, especially since it's a third hand interpretation.

    Reviews of "available literature" can be just as problematic. Again, if you really think this is something worth investigating (I personally don't), then you should track down the original study and review it.
  59. A salt lover....