salt and hypertension

Salt gets a bad rap. The oft-repeated mantra is that excessive salt causes hypertension and high blood pressure, which in turn lead to heart attacks, strokes and other cardiovascular ailments. However, this campaign has little foundation in science.

In 1972, the connection between salt and hypertension came from two pieces of research. One was the observation that populations that ate little salt had virtually no hypertension. But salt wasn’t the only thing
lacking in those diets, and any one of those could have been the cause. The second involved lab rats that developed hypertension on a high-salt diet. However, the amount these rats took in was 60 times more than what the average American consumes.

Although researchers acknowledged that the data were inconsistent, the link between salt and blood pressure became cemented in the public consciousness as fact.

A study published in the August 2011 issue of the American Journal of Hypertension, involving 6,250 subjects, found no strong evidence that cutting salt intake reduces the risk for heart attacks, strokes or death.
In fact, the risk for heart disease was 56 percent higher for the low-salt group than for the group that consumed the most salt. The conclusion the researchers came to was, the less salt you eat, the more likely you will die from heart disease, something that completely contradicts conventional views.

According to “It’s Time to End the War on Salt,” in the July 8, 2011, issue of Scientific American, “Intersalt, a large study published in 1988, compared sodium intake with blood pressure in subjects from 52 international research centers and found no relationship between sodium intake and the rate of hypertension.

In fact, the population that ate the most salt, about 14 grams [14,000 mg] a day, had a lower median blood pressure than the population that ate the least, about 7.2 grams [7,200 mg] a day. Studies that have explored the direct relationship between salt and heart disease have not fared much better.”

-- Costco Connection, September 2012

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