Projected Effect of Dietary Salt Reductions on Future Cardiovascular Disease

Extensive evidence links high-salt intake to an increased risk of hypertension and cardiovascular disease. Attempts in the United States to lower dietary salt intake by encouraging individuals to follow guidelines on recommended daily intake have been largely ineffective, and dietary salt intake is increasing. Accordingly, calls have been made for population-wide interventions to reduce dietary salt in the US diet. The investigators in this report used the coronary heart disease (CHD) Policy Model to make a quantitative estimate of potentially achievable, population-wide reductions in dietary salt of up to 3 g per day (1200 mg of sodium per day). The effect and cost-effectiveness of salt reduction was compared with those of other interventions used to reduce the risk of cardiovascular disease. Estimated rates and costs of cardiovascular disease were stratified in subgroups defined by age, sex, and race. Projections were calculated for the potential annual benefits for each subgroup with regard to reduction of CHD, stroke, myocardial infarction, and deaths from any cause. The data showed that a population-wide reduction in dietary salt of 3 g per day (1200 mg of sodium per day) would reduce the annual number of new cases of CHD by 60,000 to 120,000, stroke by 32,000 to 66,000, myocardial infarction by 54,000 to 99,000, and the number of deaths from any cause by 44,000 to 92,000. Lower daily dietary salt intake would benefit all adult age groups. Among the subgroups, reductions in stroke would be greater among women, reductions in CHD would be especially beneficial in older adults, and younger adults would have lower mortality rates. Reduction in risk for all categories would occur in blacks, especially for lowered risk of hypertension and stroke. The expected benefit for cardiovascular disease would be of similar magnitude or higher than that achieved by interventions targeting tobacco, obesity, and cholesterol. A national regulatory intervention that reduces salt intake by 3 g per day would produce a gain of 194,000 to 392,000 quality-adjusted life-years and a savings of $10 billion to $24 billion in annual health care costs. A reduction in dietary salt of only 1 g achieved gradually over the years 2010 through 2019 would result in cost savings and would be more cost-effective than using antihypertensive therapy for all persons with hypertension. These findings demonstrate the likely adverse cardiovascular outcomes for failure to reduce salt consumption in the US population and call for an immediate major public health initiative to prevent these largely avoidable outcomes.