Stephenson suggested potential restrictions could include banning TV advertisements for foods high in fat, salt or sugar before 9 pm and limiting them on billboards or in cinemas.

While low-calorie sweeteners opened a huge market of people eager to look better by losing weight, he said, salt is only a health concern, which does not have the same market potential.

The scientists also homed in on a potential mechanism: the activity of a gene responsible for helping the small intestine absorb salt and secrete bicarbonate.