Cost and health consequences of reducing the population intake of salt.

STUDY OBJECTIVE The aim was to estimate health and economic consequences of interventions aimed at reducing the daily intake of salt (sodium chloride) by 6 g per person in the Norwegian population. Health promotion (information campaigns), development of new industry food recipes, declaration of salt content in food and taxes on salty food/subsidies of products with less salt, were possible interventions. DESIGN The study was a simulation model based on present age and sex specific mortality in Norway and estimated impact of blood pressure reductions on the risks of myocardial infarction and stroke as observed in Norwegian follow up studies. A reduction of 2 mm Hg systolic blood pressure (range 1-4) was assumed through the actual interventions. The cost of the interventions in themselves, welfare losses from taxation of salty food/subsidising of food products with little salt, cost of avoided myocardial infarction and stroke treatment, cost of avoided antihypertensive treatment, hospital costs in additional life years and productivity gains from reduced morbidity and mortality were included. RESULTS The estimated increase in life expectancy was 1.8 months in men and 1.4 in women. The net discounted (5%) cost of the interventions was minus $118 millions (that is, cost saving) in the base case. Sensitivity analyses indicate that the interventions would be cost saving unless the systolic blood pressure reduction were less than 2 mm Hg, productivity gains were disregarded or the welfare losses from price interventions were high. CONCLUSION Population interventions to reduce the intake of salt are likely to improve the population's health and save costs to society.