The supply of water and nutrients is vital for our lives. Lack of these substances can lead to health problems.
Minerals are partly responsible for the "building material change" (build-up of the body tissue) and for the "fuel metabolism" (energy supply for all life processes).
The necessary quantities are involved, for example, in building bones, teeth, connective tissue, cells, enzymes and hormones. Without minerals in dissolved form called electrolytes, we would "dehydrate" even with abundant water supply. The electrolytes are indeed able to retain water in the body. However, the minerals alone would be useless if there is no water.