Salt—friend or foe?

Few issues in medicine generate as much controversy as the definition of which intake of dietary salt is optimal for health. As so often in medicine, the decision requires carefully balancing benefits and risks. On the one hand, there is indisputable evidence that, particularly in the risk populations of the elderly, the diabetic and the patient with renal disease, salt intake impacts on blood pressure and, potentially even more importantly, on cardiovascular and renal end-organ damage. Of particular concern to nephrol- ogists are recent studies documenting accelerated progression in different renal disease models, pre- sumably mediated via generation of oxidative stress. On the other hand there are concerns about the safety of generalized drastic reduction of salt intake. Where adverse effects have been documented in animal models, these were related to the stimulation of the renin-angiotensin system by very low salt intake. In our opinion, the current guidelines recommending a daily dietary intake of 6 g/day are just about right, steering clear of the Scylla of hypertension and aggravated target organ damage on the one hand and the Charybdis of inappropriate stimulation of the renin-angiotensin system on the other hand.