Misunderstood Salt: The Facts About Limiting Intake

For decades we have been told, with certainty, to limit our salt intake or risk heart disease and high blood pressure—but is this advice based on sound scientific findings? The short answer is No.

The evidence is inconsistent, inconclusive and contradictory, says prominent cardiologist Jeremiah Stamler (who used to be an advocate for the eat-less-salt campaign back in the 60s and 80s), and therefore the “eat-less-salt” message is premature and may even be harmful.

Last year, two [meta-analyses] were published by the Cochrane Collaboration, an international nonprofit organization founded to conduct unbiased reviews of medical evidence. The first of the two reviews concluded that cutting back “the amount of salt eaten reduces blood pressure, but there is insufficient evidence to confirm the predicted reductions in people dying prematurely or suffering cardiovascular disease.” The second concluded that “we do not know if low salt diets improve or worsen health outcomes.”The idea that eating less salt can worsen health outcomes may sound bizarre, but it also has biological plausibility and is celebrating its 40th anniversary this year, too. A 1972 paper in The New England Journal of Medicine reported that the less salt people ate, the higher their levels of a substance secreted by the kidneys, called renin, which set off a physiological cascade of events that seemed to end with an increased risk of heart disease. In this scenario: eat less salt, secrete more renin, get heart disease, die prematurely. […]

[Four studies] involving Type 1 diabetics, Type 2 diabetics, healthy Europeans and patients with chronic heart failure — reported that the people eating salt at the lower limit of normal were more likely to have heart disease than those eating smack in the middle of the normal range.

via The Browser