Does anyone have any info on how your hair responded to a chelating shampoo?

I’m thinking about trying one once a month to help with mineral buildup. However, I’ve been seeing some weird results (as well as great ones, but I’m more concerned about possibly damaging my hair).

I saw a pic where a woman’s hair got substantially lighter, and another where it ended up looking absolutely fried.

Anyone have any stories or before-and-after pics?