There is a lot info published to support what chinaski found, and most reference the World Health Organization. It gave me pause a while back about RO drinking water in my home. Very tough to know current info or right/wrong for the consumer. Some of it appears to be spin by carbon filter companies, but the WHO report can also be downloaded.
"If more of us valued food and cheer and song above hoarded gold, it would be a merrier world."