The body needs many minerals; these are called essential minerals.

A balanced diet usually provides all of the essential minerals.

They were often also short of essential minerals like iron and zinc.

Many essential minerals, particularly zinc, are more easily absorbed from animal foods.

Blood tests can be used to measure abnormalities in the levels of essential minerals and salts.

It also seeks out natural salt licks to satisfy its need for essential minerals.

Zinc is an essential mineral that is found in almost every cell.

The only known limiting factor on its growth is phosphorus, another essential mineral.

For people with a particularly low intake of essential minerals, especially those in developing countries, this effect can be undesirable.

But for everybody else, salt is still the essential mineral it has been since the beginning of time.