Is water important or just a filler? Is it just used to make products cheaper? What does it do for our skin? (Updated for 2024)

I was wandering around a beginning formulators’ Facebook group and saw someone stating that water wasn’t necessary – it’s just filler to make products cheaper. What? Water is an essential component of our awesome products and isn’t just there as filler! I thought I’d update this post as it’s such an important topic! Having said…