BBC News Online examines the issue of salt in the diet, and why high levels can be dangerous both for children and adults. Salt is a commonly occuring mineral, the technical name of which is sodium chloride. It is the sodium part of salt that is important. The body needs a certain amount of sodium to function properly.
Sodium helps to maintain the concentration of body fluids at correct levels.
It also plays a central role in the transmission of electrical impulses in the nerves, and helps cells to take up nutrients. In adults, when levels of sodium are too high, the body retains too much water and the volume of bodily fluids increases. Many scientists believe this process is linked to high blood pressure, or hypertension, which in turn is linked to a greater risk of coronary heart disease and stroke. With high levels of fluid circulating through the brain there is a greater chance that weaknesses in the brain's blood vessels are exposed, and that they may burst, causing a stroke. Similarly, a greater volume of fluid passing through the heart can place additional strain on the organ, increasing the possibility of coronary disease.