Nutrition is a battlefield where everyone seems to have an opinion. Some of those opinions are science-based, and others are veiled quackery with little evidence to back them up. It can be frustrating if you’re simply trying to stay healthy. Do you spend three dollars on the expensive water bottle or just drink it from the tap? Is the science behind a product’s claims valid?
Such is the case with “alkaline water,” or as I will call it for the rest of the story, basic water. It’s nearing summer again, so you might see these basic waters using marketing and a little bit of science to back a claim that somehow they’ll hydrate you better. Lots of studies seem to tout the water’s benefits, but rarely involve actually making people drink it. That means the evidence and cost don’t justify basic water as much more than rich people juice if you have a clean working tap.
“Water is wonderful,” Jo Zimmerman, an instructor in Kinesiology at the University of Maryland School of Public Health told Gizmodo. “But this is hype, not facts, at this point.”
Here’s a quick review of the chemistry if you don’t remember. Water (H2O) is made from two hydrogen atoms and an oxygen atom. Some of those water molecules break, leaving free H+ (hydrogen ions) and free OH- (hydroxide ions). If there’s the same amount of free hydrogen as hydroxide, the solution is neither acidic nor basic, and the measure of the hydrogen concentration, called pH, equals seven. If there are more free hydrogen ions, then the solution is acidic, and the pH is less than seven. If there are more free hydroxide ions, then the solution is alkaline, or basic, and the pH is greater than seven. For every whole number increase in pH, there’s ten times fewer free hydrogen ions.
This is confusing without the math but it’s because the pH scale is a logarithm of a negative exponent.