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> The idea that "salt is bad" has just as shaky underpinnings as "lower blood pressure is good".

Wait, "lower blood pressure is good" has shaky underpinnings? Is there a debate on that? I don't think there's a debate that high blood pressure results in worse (death/disease) outcomes.



It all depends. What was the starting blood pressure? How much was it reduced?

From what I've read, for those with sodium-sensitive hypertension, removing salt from the diet can be a good thing.

For everyone else, the lowering of blood pressure if pretty modest. A few mmHg?

So to answer your question, reducing your average BP from 125/85 to 120/80 doesn't have a lot of evidence of benefit.

Lowering your blood pressure from 140/100 to 120/80, has a lot of evidence for a reduction in morbidity and mortality.


"Wait, "lower blood pressure is good" has shaky underpinnings? Is there a debate on that? I don't think there's a debate that high blood pressure results in worse (death/disease) outcomes."

There's no debate that high blood is associated with heart disease. There's always "a debate" if you try to go from correlation to cause. You always have to be careful this.

You have to show that a particular mechanism for lowering blood pressure results in better outcomes. You can't unambiguously say "we've lowered the blood pressure, we know the results will be better now".


"There's no debate that high blood is associated with heart disease. There's always "a debate" if you try to go from correlation to cause. You always have to be careful this."

I always thought that high blood pressure was caused by destruction of the lining of the arteries, and stiffening of the tissue, rather than water retention.

Control of blood pressure is dependent on this delicate balance of tissues against the pumping of the heart, as well as production of the substances that allow you to be sexually active.

Hence the fortuitous discovery of Viagra whilst searching for blood pressure control medications.


I acknowledge that jumping from a to b to c (low salt to low blood pressure to less death) has gaps in causality. But why do you not take objection to his uncited assertions that low salt intake and bad outcomes together imply causality?


Where in the article does Taubes assert that? All I see him asserting is that more than one hypothesis is plausible and the evidence is contradictory.


Well, my mother had a stroke due to low blood pressure, so it's certainly not the case that lower is always better.


Indeed. But is lower blood pressure good in a person who doesn't have high blood pressure? This is a serious question too. :-)


If you have normal* blood pressure, you don't have to lower it anymore.

In fact, there's a J shaped curve for Blood pressure. Too high or too low, you're at increased risk of dying.

http://en.wikipedia.org/wiki/J_curve#Medicine

* definition of normal may change over time.


So then it sounds like one might say that lower blood pressure isn't necessarily good unless you already have high blood pressure (or are on the cusp of having high blood pressure)?


As is the case with so many things, there's a range of healthy, and it's possible to be too high and too low.

Having zero blood pressure whatsoever is strongly correlated with being dead.


You know, when I go out for a run in the mornings, it raises my blood pressure.

Should I give up exercise to become more healthy? :)


Here, let me give you a tranquilizer a day. Lower blood pressure is always good, right?


No I use leeches - they are the gold standard in medical treatment for 1000 of years.




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