More from the salt expert. This is not medical advice- it is information
only. See your doctor if you are on medication or want to treat an illness
with this information.
>
> I suppose there is a threshold for everything, like how much alcohol is
too
> much.  A threshold is implied by the question 'how much is too much?'  I
> think the safe threshold for sodium may vary with the individual.  The
> international consensus is that nothing above 100 mmol/day is safe for
> anybody. It will cause at least a rise of BP with age in virtually
everyone
> (and that is pathological --  note that half the strokes occur at a
> so-called 'normal' BP below the level needed for a diagnosis of
> hypertension and justification of medication).  If we could all be
bothered
> to get below 100 mmol/day while we were still normotensive, there is
> persuasive evidence that the epidemic of hypertension and stroke incidence
> would be very considerably reduced.  As it is, over 50% of urban
Australian
> women have hypertension before their 70th birthday according to NHF survey
> data.  This may be due partly to overweight, excess alcohol, inadequate
> exercise, relative potassium deficiency and/or stress (wrong partner,
wrong
> employer, or both) but there is equally good evidence that salt has its
> share of the blame.  We can prevent hypertension in zoo chimpanzees (just
> protect them from salt) and flint-hearted Mother Nature will continue to
> give us hypertension until we protect ourselves too.
>
> Australia was the first country to adopt a ceiling of 100 mmol (in 1982)
> and it gradually became universal, like seat belts.  It received strong
> endorsement from the Intersalt data in 1988.  David Woodward, with
> co-authors including me, published data (at present an abstract) arguing
> that a separate RDI is needed for each sex, and that 40-100 mmol/day for
> men would be 20-25% less for women.
>
> I agree that, for both incidence and prevalence, the RDI for sodium would
> probably make more difference to hypertension than to osteoporosis.  The
> obligatory urinary loss of calcium at high salt intakes gets more
important
> when advancing age impairs calcium absorption.  As the urinary leak of
> calcium is avoidable it is a pity not to avoid it at any age, but
> especially in old age.  And the current emphasis on dairy products to
> maintain calcium intake is partly to replace losses due to the prodigal
use
> of salt, and would be less applicable on the Paleodiet.
>
> In 20 years I have never seen a case of sodium deficiency as a result of
> low dietary intake.  Sodium deficiency seen when diuretics are combined
> with very low salt diets is iatrogenic -- a side effect of the drug, not
> the diet.  I very seldom see people who can excrete less than 10 mmol/day,
> no matter how hard they try.  I have seldom exceeded 30 mmol/day for the
> last 20 years, and less than 1% of Australian men have a blood pressure as
> low as mine at my age unless they are on medication (which I am not).
>
> Although it is difficult to avoid salt, I have yet to meet anyone who
could
> not be taught how to read food labels and choose low salt foods (sodium
not
> more than 120 mg/100g).
> The most motivated and most grateful patients I have ever had are the
> Meniere's patients who get rid of the vertigo without drugs or surgery.
> The least motivated are the ones who have already started medication for
> hypertension.  Motivation of the individual would be unnecessary with
> suitable reform of the food market -- Lite-Bix instead of Weet-Bix (20 mg
> instead of 280 mg/100g), Just Right instead of Corn Flakes (49 instead of
> 900 mg/100g) etc.
>