Among those now questioning the demonisation of our favourite seasoning is Catherine Collins, chief dietician at St George’s Hospital in London, who believes the current pressure to restrict salt in the diet as much as possible is unnecessary and potentially risky.

“The issue has been blown out of proportion,” Collins says. “Salt reduction is very important for people who already have raised blood pressure, but for most people who don’t have hypertension, there is no real benefit to be had from making huge efforts to cut down. It is certainly is not the dietary outcast it is portrayed to be.”

Bee continues, quoting Dr. Michael Alderman, "past president of the International Society of Hypertension" (he is also current editor in chief of the American Journal of Hypertertension).

“Only one rigorous, randomised clinical trial on salt intake has been reported so far,” Alderman says. “As it turned out, the group that adhered to a lower sodium diet actually suffered significantly more cardiovascular deaths and hospitalisations than did the one assigned to the higher sodium diet.”

Salt — sodium chloride — is an element essential for health. Every cell in the body needs sodium to function — it is required to regulate fluid balance and for nerves and muscles, such as those in the heart, to function well. Too little salt can cause mental confusion, an inability to concentrate and, in extreme cases, the potentially fatal condition hyponatraemia, which leads to body salts becoming dangerously diluted and the brain swelling beyond the skull’s capacity.

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Alderman says that, to date, most of the studies on salt-lowering have been observational, in which the diet habits of different groups are analysed to find any correlation between salt and heart health. Many of them have produced mixed results.

Finally, Bee quotes Dr. Paul Whelton, Loyola University health department president who

followed nearly 3,000 patients for 10-15 years to find out whether the salt they ate had an impact on blood-pressure readings.

After measuring the amount of salt in the urine of his subjects to assess their consumption levels, Whelton found that whether they had used the salt shaker liberally or not did not appear to make any significant difference to their risk of heart disease.

What mattered more, Whelton reported in the Archives of Internal Medicine, was the ratio of salt intake to that of potassium, another dietary mineral (found plentifully in foods such as bananas, avocado, sweet potato and tuna) that is known to balance out the artery-tightening effects of sodium.

An earlier report published in the British Medical Journal in 2002 reviewed the evidence on whether salt avoidance could lower blood pressure and found that, while it was helpful to those on medication for hypertension, there were no clear benefits for anyone else.

In summary, Bee concludes:

In countries where populations are given free access to salt, people typically consume about 5g-8g a day. “A lot of people could relax about their salt intake. If you don’t have hypertension to begin with, then just trying to eat healthily will ensure you don’t get too much,” Collins says. “Advice to cut back on salt really is the poorest of all the dietary messages around.”