Does whitening your teeth damage the enamel?

I heard it does but Im not sure. Also, Is it safer to get it done at the dentist's office rather than by drug store products?
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I was told that it is enamel-damaging when you bleach your teeth. I am not entirely sure if that is true, because the majority of my friends have told me that. In your position, I would ask a dentist to be sure but it doesn't hurt to try drug store products. Crest whitening strips are good and they seem to work, however they are expensive. (Keep in mind it would be less expensive than getting it professionally whitened.) I say ask your dentist and see what he/she says, then decide on whether you want to whiten them there or consider in investing your money on drug store products.
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