Thanks for this instructable!

I recently learned a bit about the science behind why various kinds of acids seem to be beneficial to skin care. It turns out that citric acid (found in lemon juice) is an alpha hydroxy acid; alpha hydroxy acids loosen the chemical bonds that hold your dead skin cells together, making it a great liquid exfoliant. This article where I read about alpha hydroxy acids states that they also stimulate collagen growth; the combined effect is glowing skin undulled by the layers of dead cells that would otherwise accumulate on the top layer:

http://qz.com/339922/you-really-should-be-putting-...

Now that I know that home made lemon-based toner can provide the right acids, I think I'll try making some of this for my own use.