How much more evidence do we need?

The relation between salt intake and blood pressure is no news to the food industry, nor to the expert committees in the United States, Norway, and elsewhere recommending reductions in daily intake of salt to about 100 mmol sodium or less.1 2 However, with three quarters of the presently consumed salt well hidden in processed food, there is little that people can do to influence their intake. Thus, any attempts to influence the amount of salt in food must be directed at the food industry.

Hard data are now accumulating to give substance to the debate, most notably the Intersalt study, the first report of which was published in the BMJ in 1988.3 This cross sectional study of 10 074 men and women with a broad age span was designed to describe the association between urinary excretion of sodium chloride (as a measure of salt intake) and blood pressure. After adjustments for body mass index, alcohol intake, sex, …