Beginning about 50 years ago, numerous epidemiology studies in many countries concluded that populations consuming 'hard water' containing calcium and/or magnesium have a lower risk of certain types of cardiovascular disease. These studies have not always observed the 'hard water' benefit effect, but in 2004 a committee report to WHO concluded that, on balance, the benefits hypothesis was probably valid, especially for magnesium in drinking water.  A more detailed scientific assessment of the benefits hypothesis is necessary before WHO can make a decision with respect to guidance on magnesium and calcium in drinking water.

Symposium Summary

• There is consensus that most of the world's people are deficient in magnesium and calcium, resulting in vast numbers of deaths and debilitating illnesses worldwide.
• There seemed to be agreement that there are only two ways of delivering adequate dietary Ca and Mg to the global population, without requiring consumers to change their behaviors or habits:

Adding calcium and magnesium to tap water. But that is very expensive, as 99% of tap water is not used for drinking. And, the best mineral profile for the plumbing is probably not the best mineral profile for health.  Fortifying tap water might take many years to implement. Fortifying tap water is apparently NOT the way to deliver adequate Ca and Mg to consumers. A small token effort may be made, adding a tiny 10 mg/L magnesium or calcium to tap water, but that will only make a small dent in the global dietary deficiency of Ca and Mg. 

Requiring bottlers to add the optimal calcium and magnesium to bottled products (probably 100 mg/L magnesium, and 200 mg/L calcium). This is quick, easy, paid for by bottlers, and requires no changes in consumer behavior or habits. Coca Cola's speaker said that adding magnesium doesn't change flavor, but adding calcium is harder to do without affecting flavor. Peter Featherston of Integrated Pharmaceuticals claims to have invented a calcium additive that won't impact flavor when delivering 200 mg/L calcium in beverages. Bottled beverages are clearly the MOST PRACTICAL way of delivering adequate Ca and Mg to global consumers. This will most likely will be the final recommendation in 2008, as all other alternatives are probably impractical.

• Dr. Ragnar Rylander made the important point that bicarbonate in water may improve the RETENTION of magnesium and calcium, and is therefore important.