I've read that cellulose has a lot of calories that go unused. I was wondering how practical it would be to incorporate a bacteria capable of suggesting cellulose into the human gut.
I would say that it is worth it if a human could gain a substantial amount of calories by digesting cellulose in a "normal" diet. To compute the amount of calories, I would like estimates for how fast bacteria can process the cellulose (like half life per billion bacteria) and how efficient the process would be.
Then given the average duration of the digestive process and a reasonable bacteria population, estimates could be made on how much energy could be gained by digesting the cellulose in an average diet.