+1 on first figuring out what's causing all the punctures.

+1 to what MartianDestiny said, plus how much tread is left on your tires? I usually use "multiple flats" as my tread wear indicator . If it's things like glass and nails that are causing your flats and your tires aren't worn, is it possible to (1) be more aware of what you're riding through or (2) take an alternate, cleaner route?

Some parts of the world are just loaded with thorns - on a road bike, tough tires like the Continental Gatorskins are popular. Not near as heavy as "Slime." Plus, I've never used "Slime," but I've heard lots of people complain about the mess it leaves in a tire. Maybe that's strictly tubeless tires though?

Whenever you fix a flat on the road, always check the inside of the tire carefully for whatever caused it.