Does Salt Intake Influence Blood Pressure?

Overview

Hypertension is among the most important risk factors of cardiovascular morbidity and mortality and the relation of salt to blood pressure is therefore a topic discussed by professional and layman communities for almost a hundred years. The topic is obviously controversial, the approach is surprisingly infested by emotions even in the scientific community and advocated and opponents of the idea whether salt influences blood pressure are unable to find consensus for a long period of time. Far from surprising, those who disclaim any role of salt in increased blood pressure are reporesentatives of the salt trade and the food product and canning lobbies. In contrast, the fact that in advanced countries the salt intake in human phylogenesis used to be by orders of magnitude less over hundreds of thousands of years plays into the hands of those who believe that increased salt intake participates in hypertension. Moreover, in ethnics, where a low salt intake (1–2 g/day) is still present, hypertension is virtually absent, whereas in the advanced countries, where the salt intake is commonly around 10 g/day, up to 30% of population encounters hypertension. Facts that population response to increased salt intake is different, increasing blood pressure is some and decreasing intake resulting in a minor, though significant decrease provides a new aspect.

The response to salt makes in possible to differentiate individuals into the salt-sensitive and salt-resistant subjects, where the first react to salt load by a marked increase of blood pressure, whereas those of the other group do not. It would be contributive to find some simple way to identify the salt-sensitive group, where the individuals would take advantage of decreasing the salt intake. Unfortunately such kind of identification in a all-population screening is still not possible, although the scientific community intensively searches for genetic molecular markers which could be used in this way.

In any case it is obvious that salt intake in advanced countries is higher that necessary. Based on the present knowledge it is therefore possible to recommend to control salt intake and to draw attention of the public to this fact. The other fact, mostly unknown to the public (possible to various physicians) is that increased potassium intake (vegetable food) tends to balance the unfavorable effect of sodium on blood pressure.

Reports that increased salt intake in the childhood may probably influence blood pressure in adulthood is of interest for pediatricians and sc. imprinting seems therefore possible. Therefore we should draw attention to our children eating habits and salt intake in various kinds of foods. Present way of catering in various institutions of the fast food type eg. in pupils certainly deserves such control.

Key words:
salt intake, blood pressure, salt sensitive, salt resistant, blood pressure imprinting, recommendation for salt intake