Double Boiler

I was making tea so I put the electric kettle on, filled with water to the max level. My mom told me to put less water in because she doesn't like to waste water, since it's really bad for your health to re-boil water. She said that she read this somewhere, and if I wanted proof I should just google it. She then went to Yahoo, and searched "is it ok to double boil the water." The first link read "Why does boiling water twice make water poisonous?" She was very triumphant...until we actually read the article. "well, if you read it it must be true. I read somewhere that people who believe everything they read have a serious mental deficit."