Minerals are part of the natural chemical make-up of food, especially vegetables. They are required by the body to function and are an integral part of every biochemical process. In the 1920s Ragnar Berg, a Swedish nutritional scientist, analyzed the mineral content of food. He correlated the mineral content of what was eaten with the excretion of minerals in the body. He drew conclusions about metabolic disorders and faulty nutrition based on the mineral balances. The work became known as the [acid/alkaline] effects of food on the pH balance of the body, a concept still used effectively by many naturopathic physicians.