Salt intak assessment by questionnaire and urinary sodium excretion

Limited compensation by table salt for reduced salt within a meal

Sixteen subjects, all of whom had said in a preliminary questionnaire that they normally added table salt to foods, were fed standard meals in the laboratory over 10 days. The meals were identical, except that on 5 days the meal had no added salt (containing 0.46 g sodium chloride) or had salt added to a level of 5.09 g. They were allowed free access to salt pots with the meals and used an average of 1.40 g table salt with the unsalted meal and 0.36 g with the salted meal, thus compensating for 22% of the difference in salt content of the meal. There was no difference in water consumption between the two types of meal. Nutrient intake from the rest of the diet did not differ between periods with high and low salt meals. The failure to compensate more fully for reduced salt in the foods can be attributed to the greater availability of table salt for perception; less table salt than salt incorporated in the foods is therefore required. Reduction of salt concentrations in purchased foods would be unlikely to be fully replaced by the consumer adding table salt.