Hewitt D, Neri L C
J Environ Pathol Toxicol. 1980 Sep;4(2-3):51-63.
Because of excessive reliance on the method of ecological correlation, in which the units of study are entire communities, there have been few agreed conclusions concerning the relation between mineral quality of water and health. However, in recent years there have been attempts to relate water exposure to health outcome in statistical series of individual subjects. Studies in Kitchener, Ontario and Regina, Saskatchewan found that households having domestic water softeners experience lower death rates than others. Kitchener data clearly implied an association between copper piping and mortality rate but this was not confirmed in Regina. Comparison of myocardial tissue between residents of soft and hard water areas has confirmed that insufficient magnesium intake is a likely cause of higher mortality in soft water areas. Within the 'normal' range of myocardial magnesium concentration the risk of IHD death appears to vary by at least one and possibility two orders of magnitude.
由于过度依赖生态关联法（该方法以整个社区为研究单位），关于水质矿物质与健康之间的关系，几乎没有达成一致的结论。然而，近年来，人们尝试在个体受试者的统计系列中将水暴露与健康结果联系起来。安大略省基奇纳市和萨斯喀彻温省里贾纳市的研究发现，使用家用软水器的家庭死亡率低于其他家庭。基奇纳市的数据明确显示铜管与死亡率之间存在关联，但在里贾纳市并未得到证实。软水和硬水地区居民心肌组织的比较证实，镁摄入不足可能是软水地区死亡率较高的原因。在心肌镁浓度的“正常”范围内，缺血性心脏病死亡风险似乎至少相差一个数量级，甚至可能相差两个数量级。
