Yes this is to be avoided. Whitening at all is harmful, and the book I referenced elsewhere recommends using only "Cavity Preventiion" toothpaste where the only

Yes this is to be avoided. Whitening at all is harmful, and the book I referenced elsewhere recommends using only "Cavity Preventiion" toothpaste where the only active ingredient is flouride. Also like others mentioned, pH is key - neutralizing it before brushing with an alkalizing mouthwash will help protect your enamel.