The short answer is: No.
Under microscopic examination, your teeth’s enamel looks a lot like glass rods with spaces in between them. The enamel also has very little intrinsic color and looks frosty-white to clear colored. Bleaching/whitening agents actually pass through those glass-like rods to reach the next layer (known as “dentin”), wherein the color lies and shines through the enamel. The edges of young, healthy teeth look rather clear to grayish since the edges are pure enamel. The gumline area of teeth tends to look darker since the enamel thins out there and the color of the dentin can be seen more clearly.
The middle of the teeth is a mixture, so the color is intermediate in nature. That does not mean that you may not have any side effects of such treatment. Cold sensitivity is the most common side effect. This is because bleaching agents (peroxide or carbamide peroxide) can open the pores of any exposed dentin along the gumline. Gingival recession can thin the gumline and expose the dentin layer.
Many contemporary bleaching agents contain anti-sensitivity chemicals right in the product to cut down on such sensitivity. Prescription-strength fluorides can help with this sensitivity, as well. Overall, no permanent damage occurs, and the enamel is not affected by teeth whitening.