[Incidence in myocardial infarct and mineral content of the drinking water].

In the district of Wernigerode with circa 105,000 inhabitants in the framework of a "myocardial infarction register" obligatory for the GDR during 10 years (from 1 July 1973 to 30 June 1983) all persons were registered who suffered a myocardial infarction according to the criteria of WHO, and furthermore all those patients who suddenly died before the arrival of the alarmed physician or on the way to hospital. In 3,013 cases of infarction the incidence of the infarction at the specific residence of the patient with 648 investigations of the hardness of water in a period of 10 years is compared to the study 138 investigations of the hardness of water with 138 watering places of the individual towns. The determinations of the hardness of water which regularly took place already before 1973 were regularly performed twice a year. The specific incidence and the hardness of water were compared. The level of the potassium, calcium and magnesium content in the drinking water of hard water and soft water districts was compared and the effects of a deficiency above all of magnesium on the mineral balance of man was explained.