Water and arteriosclerosis.
Consumption of hard water is presumed to protect against the development of arteriosclerotic diseases. Substantial epidemiologic correlations support the "hard water effect" as sufficiently valid to warrant alteration of public water supplies as a public health measure. A recently proposed theory that arteriosclerosis is an indolent, chronic, infectious disease caused by cyanobacteria suggests that an alternate explanation may be possible. The relationship between hard water and arteriosclerosis is reviewed, contradictions and exceptions noted, and an alternate theory of microbial infection is offered.