Role of salt intake in prevention of cardiovascular disease: controversies and challenges

Strong evidence indicates that reduction of salt intake lowers blood pressure and reduces the risk of cardiovascular disease (CVD). The WHO has set a global target of reducing the population salt intake from the current level of approximately 10 g daily to 85 categories of food; many other developed countries are following the UK’s lead. In developing countries where most of the salt is added by consumers, public health campaigns have a major role. Every country should adopt a coherent, workable strategy. Even a modest reduction in salt intake across the whole population can lead to a major improvement in public health and cost savings. Reduction in salt consumption has long been recommended to lower blood pressure (BP) and the risk of cardiovascular disease (CVD). A linear relationship between salt intake and CVD risk has recently been challenged in some cohort studies; however, methodological issues exist with these studies. In this Review, He and MacGregor discuss the relationship between salt intake, BP, and CVD risk, and describe the benefits and challenges of reducing the population intake of salt. Key points Salt reduction causes a dose-dependent reduction in blood pressure: within the range of 3–12 g daily, the lower the salt intake, the lower the blood pressure. Prospective cohort studies with salt intake measured by multiple 24-h urine collections demonstrate a direct linear relationship with cardiovascular events and all-cause mortality, down to a daily salt intake of 3 g. The totality of the evidence strongly supports a population-wide reduction in salt intake; paradoxi