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There is overwhelming evidence that a reduction in our salt intake from the current level in most countries of 9–12 g/day down to 6 g/day i.e. a 50% reduction lowers blood pressure and thereby reduces the number of people dying and suffering from strokes, heart attacks and heart failure – the commonest cause of death and disability in the world. Increasing evidence now suggests that salt has a direct damaging affect on the vascular system by increasing arterial stiffness and impairing endothelial function. These effects may be independent and/or additive to the effect that salt has on blood pressure. There is now increasing evidence that small changes in plasma sodium could play an important role. For instance, increasing sodium concentration within the physiological range has been shown to increase endothelial stiffness, reduce nitric oxide release as well as having a stimulant effect on some cell cultures. Clinical studies have shown that every time salt is eaten, even in quite modest amounts, there are changes in plasma sodium in the blood. These are associated with an adverse effect on the vascular system, increasing arterial stiffness and reducing endothelial function. At the same time, studies in patients on hemodialysis have shown that small changes in the dialysis fluid sodium which result in changes in plasma sodium in the patients, do seem to affect blood pressure at least in the short term. These studies are leading to a better understanding of the mechanism whereby salt could affect not only blood pressure but also have direct effects on the vascular system. Public health policies to get the food industry to slowly reduce the large amounts of salt they add to food have been successful in Finland, and are being successful in the UK. Every country should now adopt a coherent and workable strategy to reduce salt intake in the whole population. Even a modest reduction in population salt intake will have major beneficial effects on health, along with major cost-savings.