People frequently ask me whether they should get a water purification devices that alkalinizes the water. I don’t think alkalinizing the water is necessary. The body has tremendous buffering capacity. Changing the pH of water requires very little alkaline material. Because of the buffers, alkaline water would not make much impact on the body. Also, the stomach is supposed to be acid, so introducing alkaline water might interfere with digestion.

    Recently, I came across some information to support this. Hans Wilhelm Carl Friedenthal was one of the pioneers of acid-base chemistry. He published an article in 1903 that discussed how much acid or base it took to change the pH of serum versus water. I was unable to find his original article, but in a 1922 pharmacology textbook, the author described Friedenthal’s report as follows:

“serum requires, to secure a given change of reaction, thirty to forty times as much NaOH, and 327 times as much HCl, as would be needed in water.”

    This statement is on page 829, and Google Books has a PDF of the text:

    While I advocate filtering your water, it is not necessary to add anything to it to alkalinize it.