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Salt sensitivity levels of physical activity, caloric intakes and reduction) across the entire population, including
and the environmental stresses is legitimately open to normotensive individuals, might conceivably
question, the issue of life-long low BP among the
tendency Yanomami was repeatedly used as a justification. reduce the population incidence of cardiovas-
cular disease. This inspired the idea that a great
towards The Yanomami are described in the ethnographic number of lives and millions of dollars in health
elevated blood literature as an aggressive and violence-prone care costs might be saved through dietary salt
people. The stress associated with this character
reduction. But this notion appeared to have a
pressure is along with the continual exposure to environ- number of obvious flaws.
largely driven mental stresses does not appear to influence the In the first instance, salt sensitivity and the
by genetics BP of the Yanomami as they would other popula- tendency towards elevated blood pressure is
tion groups. While their abnormal BP profile has
and thus highly been attributed to reduced salt consumption, a largely driven by genetics and thus not evenly
distributed, but rather highly skewed across the
skewed across far more likely reason appears to be the almost population. In addition, if an intervention such as
the population. complete absence of a D/D genotype—a genetic dietary salt reduction demonstrated even a small
trait shared with other Amerindians such as the
negative effect (such as any one of the outcomes
Xingu Indians of the Amazonian rainforest, one resulting from stimulation of the renin-angioten-
of the other four outlier points. Notwithstand- sin-aldosterone system), this would tend to shift
ing their lack of an age-related rise in blood the risk curve in the opposite direction and result
pressure, the Yanomami are characterized as a in greater risk of morbidity and mortality. Finally,
small stature, high mortality and high fertility any intervention that might statistically benefit
population with a low life expectancy. It is also the public health (such as an insignificant drop in
interesting to note that despite their long history BP) may not translate into any difference at all
of evolution in a salt-limited rainforest environ- to an individual’s health —commonly referred
ment, they have never acclimatized to low so- to as the “Population Paradox.” Considering
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dium intake and have chronically high levels of the apparent shortcomings to this theory, it is
plasma renin. Nevertheless, the inclusion of the remarkable that it was so widely and uncritically
Yanomami data in the formal Intersalt analysis, accepted.
however misguided, initiated the latest round of
salt restriction efforts. FLAWED STANDARDS
The supposed merits of significant popula- The intellectual stage was thus set to estab-
tion-wide dietary salt reductions were further lish standards on salt consumption that were fun-
justified through the Rose population strategy damentally flawed. And that's exactly what hap-
theory, which contended that most risks to pened with the Dietary Reference Intakes (DRI)
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health, including hypertension, were evenly for sodium. In fact, they sank a great deal further
distributed as a continuum across the population into the mire of medical myth-information. The
rather than being confined to high-risk groups as DRI for sodium, the foundation publication for
shown in Figure 2. our current recommendations for salt consump-
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Accordingly, modest risk reductions in BP tion, clearly state at the outset that “Because of
(such as those achievable through significant salt insufficient data from dose-response trials, an
Estimated Average Requirement (EAR) could
not be established, and thus a Recommended
Dietary Allowance could not be derived. Hence,
an Adequate Intake (AI) is provided.”
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This single statement concedes, from the
very beginning, the shift away from an evidence-
based approach in establishing recommendations
to one of subjective inference: opinion. Rather
than a plea for more research to enhance the
FIGURE 2. insufficient base of evidence, the text presents
Rose Population Strategy a blunt fiat, based upon expediency rather than
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