There is no shortage of leeches... they may be the #1 easiest animal to farm in the wild.
I think they nerfed the leech and blob toxins. I take almost 0 damage from them now, so jumping right on in has been working great for me. (maxed gear, though, don't do this if you just got to swamp).

use things wisely. blood pudding is good, but onion soup and bread are fine for stam foods (eg fishing, busting rocks/chopping wood/running around) and are available in infinite amounts if you farm. Maybe black soup is not ideal to make a lot of once you have more recipes? I haven't tried a low health tough fight setup though, if going for that, its another story what to pick.