If I could give zero stars, I would. I have tried different toothpastes over time. If someone asked me to tell them which is the worst toothpaste, without any hesitation, it would be AIM White Now. The worst thing I have ever tried. Not only did I not see any difference in whitening, after thorough brushing for 3 minutes, my teeth still felt dirty, as if I hadn't brushed them at all. That's not all, during brushing, the foam changed color and turned into a dark blue, like oil paint, to the point where it permanently stained the toothbrush! Imagine how many chemicals they have put in it for nothing, since I didn't feel any sense of cleanliness. It should be noted that I prefer the AIM brand, as I am quite satisfied with their other series, such as AIM Expert Protection, which has no comparison, as if it is a different company. Unfortunately, it was a failed purchase and ended up in the trash.