For optional things like this, another game I've been enjoying, Factorio has sliders for optional mechanics. Perhaps under optional settings when choosing things like Difficulty and Exp System, you could have a checkbox with a slider for playing for "Hunger Realism" for example. The slider would be for how long it takes to need food and go to "stage 1 hungriness". Imo it should be about 30 minutes of gameplay at standard resting position of slider. Just more than the food buff lasts and enough time to reasonably keep up with it at the start.