Rob Lyons recommends you take the constant barrage of advice about lowering your salt intake a bit less seriously:
The advice to reduce our salt intake has been so ubiquitous for so long that it simply must be correct, right? Those white crystals may make our food taste better, but it’s a Scientific Fact that salt increases blood pressure and, therefore, cutting back on it will reduce blood pressure and we’ll live longer. Trouble is, while this seems to make sense, the evidence keeps failing to back it up — and a study published today raises further questions about this simplistic advice.
The new study is the latest Cochrane Review, an effort to revisit the evidence on a wide variety of healthcare interventions to provide clearer guidance to medical practitioners and patients. The review took in seven studies involving 6,489 patients. ‘Intensive support and encouragement to reduce salt intake did lead to a reduction in salt eaten and a small reduction in blood pressure after more than six months’, according to the article’s lead author, Professor Rod Taylor of the University of Exeter. But the real question was ‘whether this dietary change also reduced a person’s risk of dying or suffering from cardiovascular events’.
And the answer was ‘not really’. That shouldn’t be a surprise. Previous studies have come to a similar conclusion: reducing salt does seem to reduce blood pressure a little, but the effect on cardiovascular disease is so small as to be hardly worth bothering with. If your blood pressure is high enough that you’ve been prescribed drugs to reduce it, then there may be some benefit in also reducing how much salt you eat. But that’s about it.
