I'm not at all fond of health boosts, restoration, whatever that have crept into games from eating.
It really should be an energy decrease if you got to long without eating.
Now a slight energy increase, not as substantial as an actual stat boost, maybe a temporary +1 to perception due to increased awareness, I could go for.
The other thing I REALLY hate is turning virtually very game into a survival simulator. For most games I think we can assume the characters eat, sleep, and go to the restroom without the player needing to hold their hands.
My personal favorite food implementation was Realistic Needs and Diseases for Skyrim. Granted, it was a bit over the top, imo (suffering from an everything-and-the-kitchen-sink approach), but the
functionality was great.
Eating foods gave specific, long-lasting benefits that were catered toward different playstyles. Starving created cumulative penalties as you went through the stages. Over-eating also carried negatives, so you couldn't abuse the system. It was fun needing to consider what types of foods and how much to bring on a quest and needing to deal with what could be foraged on the road.
The downsides were that, at default settings, you spent at least 50% of your game-time gathering, making, and eating food / being sleepy and having nowhere to sleep / or getting sick because you stepped in a puddle. I tweaked it so that I only needed to eat once per in-game day, so around once every real-time hour (instead of once every 7-8 minutes), I only suffered penalties, not death, from starvation, and diseases could only be contracted from combat. That both kept the game moving and brought a lot of the lesser-used mechanics, like disease resistance / curative magic / alchemy into the light. (Found myself spending significant sums of money at the beginning on cure disease potions.
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