What is Mineral Water?

There is a lot of misconception about mineral water and the term is often used very loosely. In many articles on the web, the term is not defined at the outset and “mineral water” is often lumped together with tap water, bottled water generally, any source water, carbonated water, or even carbonated sweetened drinks. A lot of health issues, environmental issues and sustainability issues concerning sweet drinks, tap water or bottled water in general, for example, are generally applied to “mineral water” (in a sense I am using the term, defined below) without any discernment.

I have been conducting some (rather unscientific) research about general knowledge of mineral water over the last year. It consisted of asking various people a simple question: What is mineral water? Although it was not perfect or comprehensive, I still learned something from my little experiment and from observation. What I concluded is that in North America, mineral water means many different things to many different people. To some, it’s just tap water with carbon dioxide added to it, to others it is a water from a natural source that comes with or without bubbles, some think it is indistinguishable from a soda water or a seltzer, to some it is a pure water coming from an iceberg, to others it is represented by Perrier or San Pelegrino or some other European bottle of bubbly water, and some are really confused and don’t know how to define it other than that it likely has some bubbles in it. Some waiters in restaurants give you an empty look if you ask for mineral water: “You mean like sparkly water?”. No, I mean like mineral water. Do you have any? “Well, we have our own homemade mineral water that we make in the back.” No, thank you, that’s not what I mean… Deciding what the subject matter of my first few blogs should be, the choice was clear.  So, what is mineral water and how does it differ from other types of water we commonly encounter?

Generally, “mineral water” means water obtained from a geological underground source not subjected to any treatments that would modify its mineral composition. It can be naturally carbonated or non-carbonated. Wikipedia will tell you that “Mineral water is water from a mineral spring that contains various minerals, such as salts and sulphur compounds. Mineral water may be classified as ‘still’ or ‘sparkling’ (carbonated/effervescent) according to the presence or absence of added gases.” I would tweak this definition by clarifying that the gases are not necessarily “added” to the water. There are many mineral water springs containing CO2 naturally in a gas form.

Although the term “mineral water” as a term is used quite loosely in the media and by us, general public, most countries provide their own guidance and definition, mostly for food labelling purposes. Such definitions generally require that for a water to be labeled as “mineral water”, it a) has to be from some sort of a natural source or spring and b) has to have a specific level of total dissolved solids (“TDS”). Total dissolved solids refer to minerals and salts (principally calcium, magnesium, potassium, sodium, bicarbonates, chlorides, sulphates, manganese, iron, zinc, lithium, copper, selenium), cations (positively charged ions) or anions (negatively charged ions) and small amounts of organic matters dissolved in water. The level and combination of the total dissolved solids affects the taste and the beneficial properties of the water. Different countries have different thresholds for the level of the TDS contained in the water necessary for the water to be labelled “mineral water”. In Canada, until recently, the threshold for the water to be labelled as mineral water was 500 mg/l or more of total dissolved solids.  Now, any water obtained from a geological underground source not subjected to any treatment can be labeled as “mineral” or “spring” water.  In the US, the threshold is 250mg/l. In some European countries, the threshold is 1,000 mg/l. If the set threshold for the total dissolved solids is not met, the untreated water from a protected underground source can be generally labelled as natural spring water; however, such water can still contain significant levels of beneficial minerals. So, depending on what country you are, the same water could be considered to be “mineral” in one place, and only “spring” in another. I am sure this contributes to the confusion as to what one actually means by mineral or spring water, but the concept generally is that “mineral water” is a water from a natural untreated source that has some level of minerals. Since the water has to be untreated, it is important that the source you tap into is protected so that the water is safe and pure.

An important distinction between mineral waters and other waters stripped of minerals is, not surprisingly, their mineral content, or in other words, the fact that they contain electrolytes. In my next few blogs, I will discuss the electrolytes in mineral water and their beneficial properties and review various types of water commonly found on the store shelves and at homes.