Mail headline on salt 'rather simplistic'

On 5 May, the Mail said:


The article, attributed to 'Mail Foreign Service', begins:

For years, doctors have been telling us that too much salt is bad for us. Until now.

A study claims that cutting down on salt can actually increase the risk of dying from a heart attack or a stroke...

Its findings indicate that those who eat the least sodium – about one teaspoon a day – don’t show any health advantage over those who eat the most.

Needless to say, there are plenty of Mail articles saying the opposite, including: Cut salt by a teaspoon a day to save yourself from a stroke, experts say; Cutting salt from your diet 'would prevent one fifth of heart disease deaths'; Slash salt levels to save lives, food watchdog tells industry; Reduced salt intake cuts heart disease risk; and Too much salt DOES increase risk of heart attack.

But is the Mail accurately reflecting the findings of the study it is writing about? Well, despite claiming 'those that eat the least' salt show no 'health advantage', the study didn't actually investigate salt consumption - what it measured was people's urinary salt levels ('To assess whether 24-hour urinary sodium excretion predicts blood pressure (BP) and health outcomes').

And, as NHS Behind the Headlines says:

...the single urinary sodium measure analysed is not necessarily a direct indicator of how much salt a person eats. For example, it may indicate how hydrated a person is or how well their kidneys are functioning at filtering sodium.

They add:

The limitations of this study mean that on its own it does not challenge the accepted association between salt intake, blood pressure and related disease, and certainly does not suggest that eating more salt is good for you.

That is a direct response to the Mail's headline, which it says is 'somewhat unjustified', explaining:

The Daily Mail’s headline implying that eating salt is good for you is a rather simplistic conclusion from this complex study, and cannot be interpreted in such a manner.