INTERSALT study

The antisalt zealots like to point to the famous International Intersalt Study, the most comprehensive effort undertaken in this field thus far. Researchers looked at blood pressure and sodium intake in thirty-two countries. For the most part, the results revealed few links between sodium intake and hypertension in people around the world. That said, however, people in countries that had extremely high salt intake tended to have higher levels of blood pressure, while individuals with very little salt in their diets had lower levels. But these are the extremes. For most people in most countries, there was little association between salt and sodium consumption and blood pressure. And, paradoxically, people in Thailand who traditionally eat very salty diets had relatively low blood pressure levels. 

Figure 1 The relationships between sodium intake and blood pressure in the INTERSALT study. Adapted from Frost CD, Law MR, Wald NJ (1991) Analysis of observational data within populations. BMJ 302 815-818.

INTERSALT Cooperative Research Group. INTERSALT An international study of electrolyte excretion and blood pressure. Results for 24-hour urinary sodium and potassium excretion. BMJ 1988 297 319— 328. 

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