Dietary Salt Intake and Cardiovascular Disease: Summarizing the Evidence

摘要

We present a narrative review of the literature linking dietary salt intake with cardiovascular health outcomes in humans and list the tools and strategies to reduce salt intake at the population level. There is a strong agreement among experts that dietary salt intake should be reduced, targeting average population levels less than 5 g per day. The main aim of this reduction is a decline in cardiovascular morbidity and mortality. Experimental data clearly show that reducing salt intake lowers blood pressure. Considering that high blood pressure is a major cardiovascular risk factor, this provides indirect evidence that salt reduction should improve cardiovascular health.1 There is also recent direct evidence that reducing salt intake reduces the incidence of cardiovascular disease. Direct evidence linking reduction in salt intake with decreased overall and cardiovascular mortality is more limited and disputed and the data for stroke are inconsistent. Thus, there is a debate on the quality and nature of the available evidence, particularly on the magnitude of the benefit provided by the achievable reduction in salt intake. Yet, there are no known deleterious consequences of the proposed reduction in salt intake. Several countries have adopted policies aiming at reducing salt intake in the general population. The relevant tools and strategies are directed to both the food industry and the consumers. At the industry level, the most efficient measure is legislation on the salt content of selected foods, an approach much more (cost) effective than voluntary reductions. None of the interventions aiming at reducing salt intake has been rigorously evaluated. In view of recurrent controversies, any intervention in this field should be accompanied by an appropriate monitoring and evaluation program.