This product claims to be safe but is in fact not whitening your teeth. It’s using food color dyes to make your teeth appear whiter by masking the yellow in teeth with the purple dye. The dye is made up of harmful colors Red No. 33 & FD&C Blue No. 1 which are known to be Carcinogenic. Very harmful indeed. There is also Sucralose in the dye, which is an artificial sweetener & harmful to teeth. I tried to return mine but they won’t give me a refund. This is a harmful scam.