• Modern Conundrum: No Salt. No, More Salt.

    Posted May 4, 2011: by Bill Sardi

    American medicine is trying to be science based.  So what does it do when the latest science disagrees with a modern dogma – that too much salt is not good for you?

    According to the latest authoritative report, published in the most recent issue of the Journal of the American Medical Association, the less salt people consumed the more likely there were to die of heart disease.

    More specifically, those people who consumed 2.5 grams (2500 milligrams, or about a teaspoon) of salt were more likely to die than people who consumed 6.0 grams of salt (6000 mg, or a little less than a level tablespoon).

    Blood pressure did rise in the high-salt group, but not much – systolic blood pressure increased by just 1.71 points (systolic pressure is the 1st blood pressure number) for every 2.5 grams increase in sodium consumption per day.  But that certainly can’t be called hypertension (high blood pressure).  Among 2096 participants followed up for 6.5 years, the risk of hypertension did not increase with increasing salt intake.

    But health authorities are weighing in on this study and openly disagree with the science.  They claim the study was flawed and too small.  Yet it involved 3681 adult subjects who were studied for a period of ~8 years.  Naysayers even wrote an editorial that advised doctors and the public to “take this study with a grain of salt.” So what are we to make of science-based medicine?

    Sodium intake was measured by sodium concentration in excreted urine.  The lowest sodium group (2.5 grams) experienced just 10 deaths versus 24 deaths in the mid-range of salt intake (3.9 grams) and 50 deaths in the group with the highest intake (6.0 grams.   The mortality risk was just 0.8% in the highest sodium group, 1.9% in the mid-range, and 4.1% in the lowest-intake group.  That’s not just a weak statistical difference.  We’re talking a 500% relative difference here!

    An article in The New York Times cites Dr. Michael Alderman, a blood pressure researcher at Albert Einstein College of Medicine and editor of the American Journal of Hypertension, whose own study, published in 2007 showed that “there was no data to support an association of sodium intake with mortality.”

    Following the dictum of Paracelsus, a German-Swiss physician who 500 years ago said “the dose makes the poison,” Dr. Alderman’s study found over 4 grams of salt intake per day or under 2 grams per day might pose an increased risk, “with no measurable effect for the widely prevalent intakes in between,” which is the broad middle intake range for most of the world’s population.  Dr. Alderman writes that for most people who consume about 3 grams of salt a day, “the likelihood that most people would benefit from reduced salt consumption seems remote.”

    Dr. Alderman is saying this in the face of over 60 years of recommended low-salt diets by modern medicine.  Dr. Alderman goes on to say: “Evidence suggests that persons with normal kidney function can maintain stable blood pressure by appropriate alteration in sodium excretion in response to wide variation in intake.” Interpretation: the body can handle a wide range of sodium intake and excrete excesses.

    One of the good things about online publishing is that it gives readers an opportunity, via embedded links, to check on the science for themselves.   There is other science that corroborates with the idea that more salt is not harmful and may be helpful.

    For example, researchers report that for every 100 millimolar rise in 24-hour urinary sodium concentration there is a 28% lower risk for death among adult diabetics.  Science also says low-salt diets also increase the risk for insulin resistance in healthy adults.

    Salt restriction only modestly reduces arterial blood pressure by approximately 4 and 2 points for the first and second blood pressure numbers.  But any reduction in risk for heart disease is assumed, not proven.

    Modern medicine takes its eye off the target when it controls numbers rather than outcomes, or what are called end points.  The bottom line is mortality risk.  Modern medicine monitors numbers – cholesterol, blood pressure, PSA – to treat conditions, not diseases.  Are we any healthier or do we live longer because our sodium intake is lower or higher?

    Indeed, a review of 43 studies shows that restriction of salt below 6 grams per day does reduce the need for blood pressure medications by as much as 30%, but the absolute reduction in the risk for strokes and heart attacks over a period of 10-20 years is just 2-3%.

    Since salt intake is largely controlled by food producers, maybe it would be more beneficial to promote greater consumption of potassium-rich foods than salt reduction.  For every 600 milligrams of potassium increase in the daily diet there is a 0.5 to 1.0 point reduction in blood pressure.  Studies show 4700 mgs of potassium per day would typically produce an 8-point drop in blood pressure.

    Certainly dietary measures can have as much control over blood pressure as medicines do.

    Home measurement of urinary sodium excretion helps patients to control their own salt intake, and has been found to significantly lower blood pressure numbers.  Also, filling the home salt shaker with a mix of sodium-potassium-magnesium rather than pure sodium has been shown to reduce blood pressure by about 7.6 points (1st blood pressure number).  But again, any reduction in mortality is assumed.

    It is true that high blood pressure is “virtually absent in populations that consume natural foods low in sodium,” whereas in other countries where the intake of sodium in at least 10 times greater, the prevalence of hypertension is about 40% in the adult population.  High sodium levels in arteries inhibit the release of nitric oxide, a transient molecule that dilates (widens) blood vessels and controls blood pressure.  Arteries then become mechanically stiff.  However, only blood plasma changes of sodium concentration rise above 139 millimole is arterial stiffness promoted.

    If the objective is to relax arteries and control blood pressure, the provision of red wine molecules appears to restore nitric oxide levels and do just that.   Modest consumption of dark red wine (1-2 glasses per day) was shown to work in animal studies.  For tea-totalers, pills which provide red wine solids would work in a similar fashion.  And of course, there IS, contrary to salt reduction or even use of blood pressure pills, unequivocal data showing red wine reduces mortality rates for coronary heart disease.  © 2011 Bill Sardi, Knowledge of Health, Inc.  Not for posting on other websites.

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