You might find that you don’t die of hunger as much if you’re more infected. More infection means you need to have a good way to get rid of juice, but you don’t get as hungry.
Temporarily changing attributes like fatigue rate is possible but not trivial. A lot of the game balance is fairly carefully tuned, but even outside of that it’s a little challenging implementation wise to have things decay. Or maybe challenging is the wrong word. More like, labor intensive.