[Salt and blood pressure]

Current information on the relationship between sodium and blood-pressure regulation is reviewed from the point of view of epidemiological, clinical and experimental research, as well as evidence from intervention studies. Among other cations, calcium also has an influence on blood pressure. Epidemiological studies in particular are handicapped by the difficulties inherent in measuring salt intake in individuals with adequate accuracy. Despite remaining uncertainties and the need for further investigation, available data from different sources and a considerable number of studies justify the recommendation that the average daily salt intake of the population should not exceed 5 g (NaCl), corresponding to 85 meq or mmol of sodium (Na). This is a goal which should be approached gradually, paying simultaneous attention to other factors likely to be involved in the primary prevention of hypertension, especially overweight, and the maintenance of a sufficient supply of iodine and fluor for which salt is used as a vehicle in many countries.