For those of you who didn't know about this..
Take a look at the base of the tube of your chosen brand of toothpaste. Does it have a green, blue, red or black colour bar?
Here's what the colours mean:
Blue : Natural + Medicine
Red : Natural + Chemical composition
Black : Pure chemical
(Colgate is red, hence the foam according to the email.)
Now you know enough to pay attention when replenishing your toothpaste stock next. The email says to pick one with either a green or blue colour bar.
Source: Unknown - Info was received via email.