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original DRIs committee that set the first recom- A BETTER UNDERSTANDING A very recent
mendations for sodium also happened to serve as OF SALT NEEDS study
the Chair of the 2005 Dietary Guidelines Sub- Several recent publications appear to get us
committee on Electrolytes and thus evaluated the closer to what may be considered to be the human demonstrated
very recommendations that he was responsible requirement for salt. For example, a very recent that when
for promulgating in the first place. study from Harvard Medical School demon- healthy
In 2010, the process was repeated and, once strated that when healthy people were placed on
again, the same Chair of the Subcommittee on a very low-salt diet (20 mmol sodium or a fifth of people were

Electrolytes ran the show. This sequence, fully a teaspoon of salt per day), they developed insulin placed on a
sanctioned by the Institute of Medicine and the resistance within seven days. Those placed on very low-salt
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U.S. Department of Agriculture, begs the ques- high salt diets (150 mmols or 1.5 teaspoons of
tion as to whether any “independent and objec- salt) showed no such effect. We conclude that diet they
tive” analytical process can feature a single low-salt intakes warrant further investigation in developed
individual piloting the creation of standards the pathogenesis of diabetes and cardiovascular insulin
(DRIs) who then is charged with evaluating his disease.
own recommendations five years later, and asked In a series of three analyses of consecutive resistance
once again to evaluate his prior evaluations. National Health and Nutrition Examination within seven
This process makes a sham of the concept of Surveys (NHANES I, II , and III ), research- days.
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independent, objective evaluations and makes a ers were unable to demonstrate any survival
mockery of the integrity of our great scientific advantage resulting from low-sodium diets; on
institutions! the contrary, a modest relationship between
increased all-cause mortality and low-sodium
WHERE ARE WE NOW? diets was observed (although non-significant).
Notwithstanding the myths and limitations A recent study conducted to examine the
described above, the recommendations for so- health outcomes related to salt intake (as mea-
dium have been accepted, without reservation, by sured by twenty-four-hour urinary sodium),
virtually every public health agency around the demonstrated that lower sodium excretion was
world. Yet, despite the near impossibility of goal associated with an increased risk of cardiovascu-
achievement in practical terms, the recommenda- lar death, while higher sodium excretion did not
tions appear to represent a level of consumption correspond with increased risk of hypertension
that results in no more than mid-single digit or cardiovascular disease complications. 28
reductions in systolic BP for a limited portion Another meta-analysis of one hundred
of the population and a similar sized increase in sixty-seven studies by Graudal and co-workers
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BP for another limited portion of the population. confirmed and expanded upon previous reports
Several meta-analyses have seriously questioned that significant dietary sodium restriction from
the purported long-term benefits of population- greater than or equal to 150 mmol sodium (1.5
wide salt reduction, 18-21 while others have vigor- teaspoons of salt) per day down to a level of less
ously supported it. than or equal to 120 mmol sodium (1.2 teaspoons
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In fact, conflicting comment and repeated of salt) per day resulted in limited but significant
parsing of the “evidence” has become a regular reductions in blood pressure. In white subjects
feature of the salt-and-health debate, leading who were hypertensive, the mean reduction was
some journalists to complain that “almost every 5.5 mm Hg systolic and 2.8 mm Hg diastolic.
nutritional ‘fact’ is in reality an opinion, often For white normotensive subjects these figures
based on poor quality evidence.” Considering dropped down to 1.3 mm Hg systolic and 0.1
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that overall good health comprises considerably mm Hg diastolic. However, the meta-analysis
more than a single digit blood pressure response, went further to confirm and quantified the un-
the current dietary recommendations have served favorable impacts that sodium restriction had
as a decades-long red herring obscuring the need on several other risk factors for cardiovascular
for more research to get more and better dose- disease. These included significant increases in
response data. renin, aldosterone, catecholamines (adrenaline,
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