Eco friendly recommendations

I'm sure our resident Dentist will put me right but I think the recommended amount of toothpaste is about the size of a pea.
All the toothpaste ads show the toothpaste laid out along the length of the brush (so you use a lot more than a pea). I squirt it across the width, (not the length), which is more pea sized.

I use an electric toothbrush, and you can only get a pea-sized squeeze onto that

The other day my shampoo had almost run out, so I added some warm water and used the resulting thin liquid to wash my hair. Lo and behold, it was just as effective as a big blob of the concentrated stuff!

I have a second (full) bottle, so now I'm thinking that I might decant some into the old bottle and dilute it.