A few years ago, I received a newsletter from William Campbell Douglass. It was interesting to read, because his views seemed interesting, yet absurd. For example, during the era when doctors were encouraging people not to eat too many eggs, William Campbell Douglass wrote, "Not only are eggs not guilty of causing heart disease, they've been proven to prevent it". Today, it is known that eggs can in fact lower cholesterol.
At the time, William Campbell Douglass also wrote that coffee and cigars can be good for you, and that DDT is a safe chemical that can cure malaria, etc. Crazy? We'll see...
As for water... If you drink too much water, it can stress the kidney's. And, tap water, which contain fluoride can also cause Alzheimer's. But, to say, "I haven't had a glass of water in 20 years..." is misleading. He probably drinks bottled water instead.