Water Hardness in Relation to Cardiovascular Diseases and Urinary Stones

One of the most intriguing, yet, not very well defined geochemistry-health correlations is the incidence of cardiovascular diseases (CVD) in connection with water hardness of a particular area (Crawford et al., 1977; Comstock, 1979; Bernardi et al., 1995). One of the earliest studies on the relationship between water hardness and the incidence of vascular diseases was by a Japanese chemist Kobayashi (1957). He showed on epidemiological grounds higher mortality rates from cardiovascular diseases (strokes) in the areas of Japanese rivers with softer water compared to areas with hard water used for drinking purposes. Kožíšek (2003) has summarized the beginnings of research that led to the health significance of water hardness. He mentions that among the best known studies is that by Schroeder (1960) who showed a correlation between mortality from CVD in males (ages 45-64) and water hardness in 163 largest cities of the USA and who summarized his results under the caption “soft water, hard arteries”.