ABSTRACT
Salt is a chemical that consists of sodium and chloride and, as something added to food, is
not a normal constituent of a human’s or any mammal’s diet. For several million years the
evolutionary ancestors of humans ate a diet that contained less than 0.25 g/day of salt (1).
Sufficient sodium exists in natural foods to ensure that mammals could develop away from
the sea. However, chemical salt has played an important role in the development of
civilization (2). It was first found to have the magical property of preserving foods,
probably by the Chinese around 5000 years ago, when they found that meat or fish could
be preserved for a long time when they were soaked in saline solutions. This ability to
preserve food allowed the development of settled communities. Salt became one of the
most traded commodities in the world, as well as one of the most taxed. Salt was initially
expensive to produce and was regarded as a luxury, but with the mining of salt it became
much more plentiful and was added to fresh food as this food tasted bland compared to
the highly salted preserved foods that most people were used to eating. It was also found
that when salt was added to food that was going putrid, the bitter flavors were removed and
the food became edible. Salt was seen as almost magical and became a symbol of purity in
most religions. In the late nineteenth century deep freezers and refrigerators were invented
and salt lost its importance as a preservative. Since that time salt intake has been gradually
falling. However, with the increased consumption of processed, restaurant, and fast foods,
which contain large amounts of hidden salt, salt intake is now increasing. More than three-
quarters of salt intake in most developed countries now comes from salt added to
processed foods (3).
