MONTREAL, CANADA. More and more people in North America are drinking bottled water. It is estimated that consumption has grown by 400 per cent in the last decade and that one in five households now use bottled water. Researchers at McGill University have just completed an analysis of the mineral content of various bottled waters sold in North America and Europe. They conclude that the sodium, magnesium, and calcium content of the waters vary a great deal and that some are definitely very much healthier than others. They found that the magnesium content of the waters studied varied between 0 and 126 mg/liter, the sodium content between 0 and 1200 mg/liter, and the calcium content between 0 and 546 mg/liter. The Recommended Daily Allowance (RDA) for magnesium is 350- 400 mg/day, for calcium 800-1200 mg/day, and the maximum recommended sodium intake is 2400 mg/day. A low magnesium intake has been linked to sudden death from heart disease, a low calcium intake is intimately associated with osteoporosis, and a high sodium intake is believed to be responsible for many cases of hypertension. Among bottled waters commercially available in North America Mendocino had the highest magnesium and calcium content at 120 mg/L and 240 mg/L respectively (260 mg/L of sodium). Vichy Springs had the highest sodium content at 1095 mg/L (48 mg/L of magnesium and 157 mg/L of calcium). Pure Hawaiian and Sierra mineral waters were totally devoid of magnesium, calcium, and sodium while Canadian Glacier contained no magnesium and only 1 mg/L of calcium and sodium. Among European waters Apollinaris had the highest magnesium content at 126 mg/L, Contrexeville the highest calcium content at 546 mg/L and Vichi Celestins the highest sodium content at 1200 mg/L. Evian, San Pellegrino, and Vittel contained 24 mg/L, 57 mg/L and 38 mg/L of magnesium respectively, 78mg/L, 204 mg/L and 181 mg/L of calcium respectively, and 5 mg/L, 47 mg/L and 4 mg/L of sodium respectively.
Garzon, Philippe and Eisenberg, Mark J. Variation in the mineral content of commercially available bottled waters: implications for health and disease. American Journal of Medicine, Vol. 105, August 1998, pp. 125-30