So, my players are currently stuck at the bottom of an abandoned dwarf hold with water for 1 day and food for 4 days. A big part of the groups challenge in the next session will probably be trying to scavenge supplies and stay alive as they try to find a way out. So I think I will need to implement some kind of system for keeping exact track of what they have, when they spend it and what happens when they run out.

My idea at the moment:

Give each player two containers and label them "Water" and "Food".

Put three tokens in each players containers for each day they have supplies for. (So one player with water for 1 day and food for 4 days would have 3 water tokens and 12 food tokens.)

Each morning, mid-day and evening, they have to remove one token from each container.

If they are out of tokens, they receive 1 Fatigue for having no Food and 1 Fatigue and 1 Stress for having no Water.

You can use a modification of the Ogre PC rules for when he does not have meat to eat.

Just FYI: Very rudimentary starvation rules are in the equipment chapter of both the core set rulebook and the player's guide. If the players have read the book thoroughly they may have expectations about how it works. Just sayin'.

Per page 104 of the Player's Guide, starving characters officially have 1 to 2 black dice added to all die rolls, depending on how little they've eaten and how recently, but mostly subject to the GM's whims and common sense. Penalties start the day after the first day they didn't eat enough. If they didn't eat at all, it's probably 2 dice on everything, and if they ate a minimal amount it's probably 1 die per roll.

Heh, yeah no wonder I missed that. One line sneaked into a paragraph about the cost of food. No danger of my players reading it anyway, as there is only one of them who actually bothers to read rules for the games we play And they are ok with me saying "No. Screw that rule, we'll do it like this." as long as I am consistent.

I think I prefer the fatigue solution I went for. When I was in the military I had to go through a survival week where we were out in the woods hiking, setting up shelter and stuff like that with very little food. It was insane how low your stamina dropped as soon as you had not eaten properly in a while. You could go days without a proper meal without any seriously adverse effects, but just trying to exert yourself a little bit left you panting on the ground. So making Fatigue accumulate over time simulates the way hunger and exhaustion is creeping up on the characters over time. It is not a serious problem for quite a while, but if they start being overly physical, the fatigue will start rapidly accumulating.