When you're going backpacking, every bit of weight counts. One of the places where I think unnecessary weight is most commonly added is in toiletries- people bring along their regular liquid- or gel-based toiletries, so a big part of what they're carrying is just water! When I go backpacking, I like to reduce the weight in this department by making a simple, dentist-approved tooth powder. It's very simple, easy to make, and a little goes a very long way!
It doesn't taste great, though. I like to add crushed mint leaves to mine to make it taste better. I've read that you can also try adding things like wintergreen oil, though I've never tried it.
Enjoy, and happy trails!