US study questions need for most to cut salt

by Marilynn Marchione
This May 14, 2013 file photo shows salt shakers at a restaurant in Alexandria, Va. A large international study challenges the advice for most people to cut back on salt. Unless they have high blood pressure, the amount most folks consume is OK for heart health, and too little may be as bad as too much, the study suggests. (AP Photo/Cliff Owen, File)

A large international study questions the conventional wisdom that most people should cut back on salt, suggesting that the amount most folks consume is OK for heart health—and too little may be as bad as too much. The findings came under immediate attack by other scientists.

Limiting salt is still important for people with high —and in fact, a second study estimates that too much contributes to up to 1.65 million deaths each year. The studies both have strengths and weaknesses, and come as the U.S. government is preparing to nudge industry to trim sodium in processed and restaurant foods.

The first study's leader, Dr. Salim Yusuf of McMaster University's Population Health Research Institute in Hamilton, Ontario, urged keeping an open mind.

"There are those who have made a career out of promoting extreme sodium reduction that will attack us," he said. It's better to focus on healthy lifestyles and overall diets instead of a single element, "and that is something everyone can rally around."

No one should view this as permission to eat more salt, he said, adding that "most people should stay where they are."

The studies are in Thursday's New England Journal of Medicine.

Yusuf's is observational, rather than a strict experiment, and has big limitations in its methods. But its size lends strength—more than 100,000 people in 17 countries, the largest on this topic. It's also from a general population, not just people at high risk of heart disease, as many past studies have been.

Researchers found:

—Sodium levels generally correlate with the risk of high blood pressure. But this link is strongest when sodium intake is high and wasn't seen at all when consumption is low. The link also is stronger as people age.

—A different nutrient—potassium, found in vegetables and fruits—seems to lower blood pressure and heart risks, and offsets sodium's effect.

—People who consume 3 to 6 grams of sodium a day (about 8 to 15 grams of salt) had the lowest risk of heart problems or death from any cause during the nearly four-year study. More or less sodium raised risk. About three-fourths of the world's population is in the ideal range. Americans average roughly 4 grams a day.

Guidelines from various groups for heart disease prevention recommend 1.5 to 2.4 grams of sodium a day. The American Heart Association advises no more than 1.5 grams.

"These are now the best data available," Dr. Brian Strom said of the new study. Strom, the chancellor of Rutgers Biomedical and Health Sciences, led an Institute of Medicine panel last year that found little evidence to support very low .

"Too-high sodium is bad. Too low also may be bad, and sodium isn't the whole story," Strom said. "People should go for moderation."

The study was sponsored by the McMaster institute, nonprofit and government groups and industry, but funders had no role in running it. The countries included Canada but not the United States; China accounted for 42 percent of participants. About 40 percent had high blood pressure.

In this Feb. 7 2012 file photo, an employee holds packets of salt at a market in Cleveland. A large international study challenges the advice for most people to cut back on salt. Unless they have high blood pressure, the amount most folks consume is OK for heart health, and too little may be as bad as too much, the study suggests. (AP Photo/Amy Sancetta, File)

Sodium levels were estimated from a single urine test instead of the preferred method of over 24 hours at multiple times, which Yusuf said was impractical in such a big group.

That drew criticism from a host of scientists.

"This is a fundamental flaw" that undermines confidence in the results, said Dr. Elliott Antman, a Brigham and Women's Hospital cardiologist who is president of the Heart Association.

Dr. Robert Eckel, a University of Colorado cardiologist and a former Heart Association president, said the single measure is a big limitation, but that researchers "did the best they could" in such a large study and that the findings still have some merit.

"I find the potassium data of great interest" for potentially lowering risk, he said.

Dr. Martin O'Donnell of McMaster University, one of the researchers, said potatoes, bananas, avocados, leafy greens, nuts, apricots, salmon and mushrooms are high in potassium, and "it's easier for people to add things to their diet than to take away" something like salt.

The second study in the journal, on how much sodium contributes to heart-related deaths, was led by Dr. Dariush Mozaffarian of Tufts University and the Harvard School of Public Health, and funded by the Bill and Melinda Gates Foundation. Researchers looked at dozens of studies around the world on , calculated its relationship to high blood pressure, and then the relationship of high blood pressure to cardiovascular deaths.

There were 1.65 million deaths from intake over 2 grams of sodium a day, they estimate, and half a million deaths based on current worldwide consumption of 4 grams a day, said Mozaffarian, who has consulted for some food makers.

His study is less controversial and shows why policies to curb salt are important, Michael Jacobson of the consumer group Center for Science in the Public Interest, wrote in an email.

The federal Food and Drug Administration is preparing voluntary guidelines asking industry to trim sodium in processed foods, the main source in the diet.

"The totality of the evidence strongly supports" limiting sodium, Antman said, and the Heart Association feels "now is the time for action and not hesitation anymore."

Nutrition scientists Marion Nestle at New York University agreed.

"People don't eat salt, they eat food," she said. "Lots of people have and lots of people are getting older," making salt a growing concern, she said. "That's the context in which this is taking place."

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Padre53
1 / 5 (2) Aug 14, 2014
Again the pseudoscience of salt. Dr. Salim, You must think again. This single element (sodium) is perfect food of entropy. The salt is the greatest blunder of Homo Sapiens. The elite of the health science made experimental animals from the humanity. And all of the humanity suffers from Sodium-Induced Disorder Syndrome (SIDS)! The (pseudo)science of salt is the number one perfect example onto the blunders, mistakes and irresponsibilities of the modern health sciences.
http://www.scienc...s-120016
http://padre.uw.h...udal.htm
http://www.ration...ropy.htm
FainAvis
not rated yet Aug 14, 2014
Pardre - Do try to construct proper English sentences lest your musings will be dismissed as word salad and gobbledegook.
aksdad
2.5 / 5 (2) Aug 15, 2014
For the most part a well-written article that highlights the fact that cautions to decrease salt intake for the general population are not based on solid science. The comment that the second study is "less controversial" doesn't improve the accuracy of the study's conclusions. Level of controversy has no scientific merit. The fact that it's a meta-analysis, or a study of several other studies, is suspicious. Summarizing other research doesn't further knowledge, especially if you only summarize research favorable to your conclusion and ignore research that isn't.

I happen to have low, "healthy" blood pressure and never worry about salt intake. If I had hypertension I might monitor my salt consumption. Since the research isn't definitive, I'd try an experiment on myself. If lowering salt consumption noticeably reduced my blood pressure, I'd cut back on salt. If it didn't, I wouldn't worry.

Ultimately high blood pressure is the problem; salt consumption may not be.
Padre53
1 / 5 (1) Aug 15, 2014
aksdad
solid science. ... high blood pressure is the problem.
You must think again. The "solid science" of salt is ignored and censored! The high BP is only a little part of many adverse effects, including censored (secret) acute effects of unnecessary Na-intakes (above the optimum). Five decades global censorship and corruption - this is the "so called science" of salt. http://padre.uw.h...udal.htm
Padre53
1 / 5 (1) Aug 15, 2014
"Although the Salt Institute embraces the Data Quality Act, it fears the Food, Drug, and Cosmetic Act. That law requires that substances in food be restricted to safe levels. However, salt is considered by the US Food and Drug Administration to be 'generally recognized as safe', which means that levels cannot be restricted. The Center for Science in the Public Interest in 1978 petitioned the Food and Drug Administration to revoke the generally recognized as safe status and limit salt, especially in the biggest sources of sodium. ... After the Food and Drug Administration failed to take action, Center for Science in the Public Interest sued the Food and Drug Administration (unsuccessfully) in 1982 and 2005, and later in 2005 again petitioned the agency to protect the public health. ... It is unfortunate that government health authorities have not shown the will to act."
http://www.nature...51a.html
Padre53
1 / 5 (1) Aug 15, 2014
March 20, 2014 "Previous research found that protective ends on chromosomes (telomeres) naturally shorten with age, but the process is accelerated by smoking, lack of physical activity and high body fat. The current study is the first to examine the impact of sodium intake on telomere length."
http://blog.heart...n-teens/
And: 9 September 2013 "The average lifetime of our cells shortens. Soon (faster) the telomeres run out. Our aging accelerates. We get sick often and we will die soon."
http://www.scienc...s-120016
Padre53
2.5 / 5 (2) Aug 15, 2014
Why big data & fancy statistics aren't science?
Eight (no, nine!) problems with big data
http://www.nytime...ata.html
"By combining the power of modern computing with the plentiful data of the digital era, it promises to solve virtually any problem - crime, public health, the evolution of grammar, the perils of dating - just by crunching the numbers."
The researchers are not thinking, the existing knowledge is not used (it is ignored and censored), but statistical data are collected. Instead of statistics would be better to learn more and to think more.
snowflake0446
2 / 5 (3) Aug 16, 2014
There is sufficient evidence to show that insulin (release by the pancreas), not salt, actually increases blood pressure. Too much sugar is the main culprit. Insulin tells the kidneys to hold on to water resulting in increased blood plasma resulting in higher blood pressure. When I increase my sugar intake (to include complex carbs), I can get my BP to go up to 139/90 and then when I cut back on sugar, it goes back down to 120/80. Yes salt does have an affect, but it's minor at best. That's why it's impossible to lower your blood pressure to acceptable levels despite taking in NO salt whatsoever, why people with high BP's have to take diuretics. Why don't scientist get this? Why is this so difficult a concept to understand? It's like they're looking at the tip of the iceberg and seeing salt without seeing what's underneath...insulin's ability to tell kidneys to retain water.
thixotropic
1 / 5 (2) Aug 17, 2014
(+1 on Padre53's comment)

Salt that comes from the evaporation of sea water is necessary to human health, and is actually critical to proper control of blood pressure. Sodium compounds in different forms are heavily used by agribiz giants because flavors (and nutrients) don't survive the extremely heat- and pressure-intensive processing.

MSG is neurotoxic: the reason we all get sleepy from MSG is that our bodies release a ketamine-like substance to combat that excitotoxic compound. The enemy isn't salt -- we need real salt. It's these sodium compounds that raise blood pressure and are bad for our health.

So what is the American government seeking to regulate? Salt.
thixotropic
1 / 5 (2) Aug 17, 2014
"The Center for Science in the Public Interest in 1978 petitioned the Food and Drug Administration to revoke the generally recognized as safe status and limit salt, especially in the biggest sources of sodium. ... "

This is a common but crucial error: the problem is not salt. It is *sodium*. Confusing them or lumping them into the same category is dangerous when we're talking about what to restrict! Many genuine, traditionally prepared, high-quality foods like cheeses require a hefty amount of salt in their preparation. This is why the corporate food giants are pressuring the government to regulate salt, but not sodium: to kill the competition that real and wholesome foods represent for them.
Padre53
1 / 5 (1) Aug 17, 2014
snowflake0446
Too much sugar is the main culprit.
No! "The Recommended Dietary Allowance (RDA) for carbohydrate is set at 130 g/d for adults and children based on the average minimum amount of glucose utilized by the brain. This level of intake, however, is typically exceeded to meet energy needs while consuming acceptable intake levels of fat and protein (see Chapter 11). The median intake of carbohydrates is approximately 220 to 330 g/d for men and 180 to 230 g/d for women."
http://www.nap.ed...page=265
3-4 liters of human milk contains: 227-303 g carbohydrates, 1990-2650 kilocalories energy, 405-540 mg sodium and 1410-1880 mg potassium. Source: Yamawaki et al. 2005.
http://www.ncbi.n...16325533
The much sugar or the much sodium is the reason of the diseases?
Padre53
1 / 5 (1) Aug 17, 2014
thixotropic
Salt that comes from the evaporation of sea water is necessary to human health,
No! The natural sources of our mineral requirements (P, Ca, Mg, Na, K, Fe, Mn, Zn etc.) are plant and animal origin foods (and little amounts from drinking water)! And not the salt (= NaCl), and not other salts! Sodium is sodium, MSG and NaCl are perfect food of entropy! The salt is the greatest blunder of the Homo Sapiens. Only the man nourishes the entropy in his own body. There are not free-living animals like this on this Earth. The entropy and the natural selection destroyed the such species. (The natural selection already has little effect to human genome, does not repair it already.) The salted humanity genetically degenerates and will be idiotic.
Padre53
1 / 5 (1) Aug 17, 2014
snowflake0446 1985! "There is a growing evidence for that in modern societies the function of the cellular sodium-potassium pump (membrane-bound Na+ K+ ATPase) in several tissues in man cannot respond adequately to demands. This is not seen in any other free-living vertebrates on this earth. The clearly unphysiological very high intake of sodium-chloride (salt) and also alcohol is definitely playing an important role in the development of the common degenerating metabolic aberrations, e.g. essential hypertension, diabetes II and severe over-weight, in man. The special and overall important role of the sodium-potassium pump for optimal cellular function and regeneration with special reference to the vascular tissues is presented and discussed." http://www.ncbi.n.../2582182
Forgotten and ignored knowledge.
Padre53
1 / 5 (1) Aug 17, 2014
2010! "Patients are advised to stay away from fatty foods, which obviously does not help because fatty meal is not the cause for atherosclerosis. Therefore, the researchers should first examine the cause of the disease before trying to cure it; otherwise, we will be treating symptoms rather than curing the disease itself. ... We have a mission but are lacking the vision. That is why we have not made any progress even though we have worked on it for more than 50 years." http://www.ncbi.n...2945206/
Five decades global censorship and corruption.
Padre53
1 / 5 (1) Aug 17, 2014
1965! "The rate of anaerobic glycolysis, as determined by lactate formation, correlates well with the rate as determined by glycogen utilization. Using lactate formation as the index of anaerobic glycolysis, a linear relationship was observed between glycolysis and net anaerobic sodium transport." http://europepmc....C2195440
Forgotten, ignored and censored knowledge!
Padre53
1 / 5 (1) Aug 17, 2014
http://www.ncbi.n...2278526/ 2010! The results proves clearly, the excess salt intake (the higher energy expenditure of the Na-K pump and kidney, against entropy) do not increase the oxidative pathway, in rats. (I notice it: the decrease would be logical? Yes, it is logical consequence of the sodium-induced disorder. And I think, the decrease is fact!) But a critical surplus switches the anaerobic glycolysis on, and produces lactic acid in every cells. We can calculate that this anaerobic energy (ATP) production consumed more glucose (from the glycogen reserve) than the total resting metabolism of the rats, on the oxidative pathway. Despite, that this anaerobic excess isn't more than (about) 10-15 % of the total resting metabolism of the rats. And after the infusion of the highest dose of salt, 3 hours was not enough to return to the baseline level (to the level of resting metabolism). This is a real Sodium-Induced Cellular Anaerobic Glycolysis (SICAG).
snowflake0446
1 / 5 (1) Aug 18, 2014
Padre53 - First, thank you for taking the time to respond. I do appreciate the effort you went through. Next, I'm still new to how ncbi works. I can see the abstract, but where's the study? I would appreciate info. on how to open the entire study showing how they came to the conclusion of Na+, K+, ATPase play an important role in hypertension, diabetes II, etc. Without that information, I'm still not convinced by the 1985 study abstract. Perhaps the complete text will help.
snowflake0446
2 / 5 (2) Aug 18, 2014
Padre53. I'm in total agreement with the quote you used from the 2010 study. For me, I believe that more of the evidence for origin of atherosclerosis seems to point to enterobacter hormaechei: http://phys.org/n...is.html. I, myself, do not fear saturated fats. I just believe that they must be balanced with the appropriate non-inflammatory Omega-3, 6, 9 fatty acids.
snowflake0446
1 / 5 (1) Aug 18, 2014
Padre53 - I'm a huge fan against the RDA because of how it was created and evolved. Simple example. RDA recommendation for Vit. D = 600IU's. But now a number of studies show the form D3 is easily absorbed and beneficial at 8000IU's. Just one example. What I want is optimal performance. I'm not looking to simply avoid disease. So for babies...yes, whatever breastmilk contains is fine. But for an athlete (which I'm working toward), I believe the man/woman ranges are too high. Our bodies do fine with ketones as long as we maintain appropriate pH balance. I don't understand the fear involved because in order to lose weight, we need to produce/metabolize ketones. http://droualb.fa...eled.jpg (nice picture). I myself am limiting my carbs to 40g/day, but can easily see increasing as needed.
snowflake0446
2 / 5 (2) Aug 18, 2014
I'm totally against any sort of Government regulation. I am for information though. People should be informed and then allowed to make their own decision about salt and everything else. I'm also against Government bailout as well. So if someone puts themselves into a predicament due to poor choices, then it's up to family/friends to bail them out...not the Government. I use salt. I know that too much salt is bad, like to much of anything. But there are acceptable amounts. Salt is a necessity for human health. Look up "water intoxication".
snowflake0446
1 / 5 (1) Aug 18, 2014
Padre53 - So I'm not following what the thermogenesis in rats have to do with high blood pressure. I would appreciate your help. Some background. I've had College Biology...and that's it. But I do enjoy learning biochem and hope to take a course soon so that I have all the foundational information. Again, I appreciate your help and your taking the time to respond with such detail and good studies.
thixotropic
1 / 5 (1) Aug 18, 2014
"MSG and NaCl are perfect food of entropy! The salt is the greatest blunder of the Homo Sapiens."

Um. Okay. This sort of thing mitigates against your making your point, here.
We require both sodium *and* chloride to survive. MSG has no chloride, it has no place in our diets, and it is not the same as sea salt. It's also an excitotoxin. Salt is not.
Padre53
1 / 5 (1) Aug 18, 2014
thixotropic
Can you understand this?
Sodium-Induced Cellular Anaerobic Glycolysis and Sodium-Induced Disorder Syndrome?
http://www.realcl..._quotes/
Padre53
1 / 5 (1) Aug 18, 2014
snowflake0446
The high BP is only one of many chronic consequences of SIDS, but the sodium-induced disorder has many acute dangerous (deleterious) effects (acute consequences).
Henningsen is very important, but not enough to explain the exact and complex mechanism of the development of high BP, which has many other risk factors and there are individual differences (genetic, behavioral etc.). For high BP, need more, e.g. Mathur, Meneton et al, Dickinson et al (ref. 10, 11 and 12). You can read these articles and much more, but?? I'm chemist and my work is analysis by (ICP-MS), I cannot deal with all illnesses in detail as e.g. Kleinewietfeld et al ref.31. And the real science of salt is only in traces in scientific papers.
(I have full Henningsen 1985, but where? The entropy is growing in my computer and external winchesters, but i will find it.)
snowflake0446
1 / 5 (1) Aug 19, 2014
Thixotropic - I'm with you on MSG. It causes pain to increase in our nervous system (excitotoxin).

Padre53 - Thank you for looking. I'll check back tomorrow to see if you were able to find the document. I totally understand the overwhelming amount of data you have on your HD. :-)
thixotropic
1 / 5 (1) Aug 19, 2014
So, Padre53... how does your unsalted humanity digest its food? It's not going to be using stomach acid: You need chloride for that.

You said that free vertebrate animals don't consume salt. Ungulates and ruminants certainly do; wild and domestic -- and if you don't provide your stock with a salt lick (most of which contain several other minerals as well) they will not be healthy. They'll even die.

Padre53
1 / 5 (1) Aug 19, 2014
snowflake0446, You can download the full article:
http://padre.uw.h...1985.pdf
Padre53
1 / 5 (1) Aug 19, 2014
Wise Thixotropic, the natural foods (animal and vegetal) and drinking water contains Cl, P, S etc. also. We dont need salt(s) intakes. Your viewpoint is extremely narrow. (And in the rain forests, you can lick - what?)
"From an evolutionary viewpoint, the human species is adapted to ingest and excrete less than 1 g of salt per day." (salt = NaCl)
Meneton et al. 2005
http://www.ncbi.n...15788708
http://physrev.ph...679.long
snowflake0446
1 / 5 (1) Aug 20, 2014
Padre53 - Thank you for the article. I'm reading through it now.

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