Epidemiologists have been gathering evidence concerning increased cardiovascular mortality rate that has been rising gradually for the past fifty years, they believe environmental factors are playing a key role in influencing the mortality and the highly suspected factor is the hard water. Hard water can simply be defined as water with high mineral content, according to the world health organization hard water has high polyvalent metallic ions dissolved in it where the prevalent are calcium and magnesium but there are also other metallic ions such as iron, aluminum, manganese, barium and zinc which contributes to the water hardness. The traditional method of measuring water hardness is the ability of the water to react with soap, where hard water is determined through its poor ability to produce foam. Calcium carbonate is the main metallic ion considered when categorizing water hardness, soft water has calcium carbonate below 60mg/l where water with calcium carbonate 60-120mg/l is considered moderate hard while hard water has between 120-180 mg/l . Read here about having sufficient essential minerals such as calcium and magnesium which are vital for human health, for example calcium is required by the body to strength bones and vital in pregnant women, and old people, calcium deficiency is associated with kidney stones(nephrolithiasis), hypertension, obesity, insulin resistance and some other health conditions, human body need magnesium to produce enzymes that body needs to generate energy for metabolism, lack of enough magnesium has been associated with , cardiac arrhythmia and pre-eclampsia (gestation hypertension). The benefits of these minerals are only realized when they are provided at an optimum level implying that consuming them in excess as may be in the case of hard water can be harmful to human health. This article therefore has gathered some essential information regarding the health effects of consuming excess minerals that are mainly found in hard water.
Consuming excess calcium salt in hard water may not be dangerous to healthy individuals because they are protected from excess calcium intake by intestinal absorption and other elimination mechanisms, here the excess calcium is excreted by the kidney, however, for people with the renal problem (kidney issues) as well as those with the milk-alkali syndrome are more at risk of excess calcium intake, therefore, the need for concern of consuming hard water.
Taking hard water with high magnesium mineral has not been proofed a health risk especially to a healthy population, however, people with renal insufficiency will experience bowel discomfort such as diarrhea but this is adaptable, additionally, consuming water with high magnesium level has been linked with laxative effects, but there has no strong relationship found between consumption of hard water with high magnesium and calcium level with cardiovascular mortality. These are the main health concerns about the drinking of hard water. Click here for more information on this topic: https://www.britannica.com/technology/water-softening.