What's really crazy is that is completely different from how it works in life. Vitamins don't do ♥♥♥♥ against food poisoning or the plague. Food poisoning rarely kills you and you rarely get it unless the food hasn't been cooked right. A17 got the mechanics right for canned foods and stuff giving food poisoning: most of that stuff would have been expired by now. For the fresh meat though (Regarding the A18 comment)? As long as you cook it properly and eat it without it sitting in the fridge for weeks at a time, you won't get sick. We really just need food spoilage. A simple timer on the item and then it turns rotten. Without working refrigerators, it'd go from good to questionable to spoiled within a few days.
I think what I'm getting at here is fix the problem: Food lasts forever. Instead, ensure the player always has to eat bad quality food unless they killed that boar, cut open it's carcus, and cut out the meat within the past 2 days or so. That along with a reduction in meat (I got 55 meat from a boar last night in A17) that each animal gives would make it feel more survivalist. The user shouldn't be allowed to see the spoilage timer either, and it should be randomized a bit to be unpredictable. Between that and tying hunger to game hours and thirst to how active you are (and hence: how much you sweat), you'd have a pretty interesting system where most food would be questionable at best or bad, and the only good food you can eat would be fresh off a bear's ass. (or boar, or deer, but bear sounded better)