The proponents of alkaline drinking water claim that it can increase stamina, reduce aging and prevent cancer, among other benefits. An equally vociferous opposition calls the water "snake oil." Like most differences of opinion today, this debate is all over the Internet.

A working definition of alkaline drinking water might be explained beginning with the water molecule being composed of hydrogen and oxygen. Under normal chemical processes, one in approximately 10 million of these molecules will ionize, which means splitting into hydrogen and oxygen ions. Hydrogen ions are acidic, while hydroxyl (oxygen) ions are alkaline. Thus, water will take on the pH value of whichever ion is most abundant.

According to one alkaline drinking water advocate, purewatersystems.com: "It is this abundant amount of hydroxyl ions that neutralizes acid hydrogen ions in our body to reduce the accumulated acid wastes, thus reversing the aging process." How can it be determined which ions will "win"? The advocates of alkaline water talk about "restructuring" water electronically, although it is difficult to pin down exactly how this is done.

An explanation of alkaline drinking water from nutritionist Dr. Theodore Baroody, author of the book Alkalize or Die, is typical: "The newest concept in drinking water today is electronically restructured alkaline water. This method yields alkaline drinking water and has another facet that I find particularly interesting. It lowers the millivoltage of the water. This means that the water molecule is reconfigured into a lighter, simpler form that is definitely more alkaline product, but there is a hertz frequency change that is beneficial."

On a more down-to-earth level, those who espouse the virtues of alkaline point in comparison to the acidity of some of our most popular beverages, such as coffee and most sodas, and credit alkaline drinking water with changing the body's pH to a more benign and beneficial balance. Yet some medical professionals claim that it is not possible for foods to change the acidity of anything in the body except for urine.

These professionals point out that the stomach is naturally acidic, hence it is able to break down foods -- while the fluids in the intestine must be alkaline to prevent damage from the acid. It is the kidneys, he points out, that regulate the pH of the bloodstream, not the outside influence of drinking water. However, regardless of beliefs, alkaline drinking water has spawned a cottage industry ranging from machines that purport to "ionize" neutral water to squeeze bottles of alkaline drinking water that are prescribed in very small daily amounts.