The researchers pointed out that their experiments did not address whether collagen and other proteins in the teeth can be regenerated, so it is unknown if the tooth damage is permanent.
Americans spend more than a billion dollars on teeth whitening products each year. But aside from the environmental harm from all the waste generated - the strips, trays, all that packaging - haven't you ever wondered if it is OK for the teeth?
Researchers conducted three studies and found the active ingredient, hydrogen peroxide, can damage the protein-rich tissue located beneath the enamel.
Dr Kelly Kennan, from Stockton University in New Jersey, said: "Our results showed that treatment with hydrogen peroxide concentrations similar to those found in whitening strips is enough to make the original collagen protein disappear, which is presumably due to the formation of many smaller fragments".
Previous research has shown that hydrogen peroxide can penetrate the enamel and dentin.
Dentin lies beneath the tooth's enamel outer layer and provides it with support. "We used entire teeth for the studies and focused on the impact hydrogen peroxide has on the proteins".
In the new work, the researchers demonstrated that the major protein in the dentin is converted to smaller fragments when treated with hydrogen peroxide.
The most common side effect that dentists see after the use of whitening strips is tooth sensitivity, which is transient and does not represent underlying damage of the tooth, he said.
The findings were presented during the 2019 Experimental Biology meeting held in Orlando, Florida.
The American team found that collagen protein in the dentin was broken up and appeared to vanish from laboratory images.