If you were looking for teeth whitening in UK or the US
The fact that mint cosmetics is a new product does speak to some about the quality of effectiveness or impact on your teeth. However, while it is not particularly harmful, mint cosmetics as a teeth whitening kit often fails to provide the best results. This is not because they are left with bad options or ingredients but with ones that are simply ineffective at best. This is because mint cosmetics uses sodium bicarbonate, which is a much weaker substitute for the conventional carbamide peroxide, which means it has absolutely zero peroxide - with the latter being used by most conventional teeth whitening products online as well as offline.
So while you look for the best home teeth whitening products, you need to give mint cosmetics a skip if you want the best results within the shortest period of time. This is more so as the FDA approval for the mint cosmetics gel is for the type of gel used and not the gel itself. This is a serious loophole that a lot of tooth bleaching products capitalize on, and you need to be wary of the same too.
The second point is the lack of actual certificates displayed online - which is a huge counter to people believing that it has FDA approval. Moreover, the amount of gel that is sold is not as large as it is assumed to be when compared to other established home teeth whitening kits like Dental White (from Smile4You.com) etc. A typical kit form the latter has around 120ml/cc while one from the mint cosmetics brand has only 12 ml/cc. While this may not be a criterion for you to keep mint cosmetics out of your shortlisted products, the zero peroxide problem is more of a concern.
While sodium bicarbonate is a cleansing agent too, it is weaker, which means that the teeth whitening results claimed by the product even through a zero peroxide percentage can be the gateway to irritant side effects from masked ingredients used in the same. While other products are kept under scrutiny in the factories by the FDA, this is not mandatory for all - and again is capitalized by a number of tooth bleaching brands to attain their vested interests.
While zero peroxide in mint cosmetics may not have troubled you and you chose to go along with the product, ensure that you ask for a trial before you use the product on the long-term!