The coloured stripe at the bottom of toothpaste tubes conveys a very important message that most people are unaware of.
These different colours are meant to give you an idea of the main ingredients of the toothpaste. What you need to do is to take a close look at the bottom of the tube, where you will find a coloured stripe.
Below is a list the colour stripes commonly seen at the bottom of toothpaste tubes and what they represent. However, there are opposing claims that they have nothing to do with the ingredients of the product. So all you have to do to confirm for yourself is to look at the list of ingredients used to produce the product.

Green – All Natural

Blue – Natural + Medicines

Red – Natural + Chemicals

Black – All Chemicals.
Cheers!!

lyk seriously?? never knew sha.

wat of pink?

This claim is completely false.
http://www.hoax-slayer.com/squares-on-tube-hoax.shtml