Typically, characters can get sick from eating spoiled or improperly prepared foods. A check for food poisoning is always required with the cook rolls a critical fumble. In this event, each character that ingests the spoiled food must make a save versus poison or succumb to food poisoning. Typically, food poisoning follows a fairly predictable path. The onset of sickness is typically 2d6 hours after ingestion.
On the first day, the character is wracked with projectile vomiting and diarrhoea. The victim may experience incontinence. This makes combat impossible and wearing armour impossible.
On the second day, the character still suffers from bouts of diarrhoea and can only drink water. Fluid requirements are quadrupled. Combat is possible, but most actions that require even modest stamina or concentration are penalized at -8.
On the third and fourth day, diarrhoea subsides, and the character can eat simple foods such as soup, crackers, and plain bread. Fluid requirements are tripled. Characters can wear Light armour, but nothing heavier.. Most actions are penalized at -4.
On the fifth and sixth day, the character can eat most normal food that is not overly spicy. Fluid requirements are doubled. The character can wear up to Medium armour, but still cannot withstand Heavy armour. Most actions are penalized at -2.
On the seventh day and beyond, the character's heath is normal, though their opinion of that particular chef or eating establishment has undoubtedly been reduced permanently.