Metro isn't open world, and doesn't require eating/sleeping/anything. They're great games, I already bought both and I'll buy the Redux again, but probably not what he's looking for.
State of Decay is an option. Open world, third person zombie survival. Requires scavenging supplies and resting.
7 Days To Die is another zombie option. First person, procedurally generated base-building open world game. Requires scavenging for food, water, and building materials. Still in progress, but entirely playable.
Fallout New Vegas is a first or third person (third person in that game is terrible though) open world shooter/rpg hybrid, with a hardcore mode that requires drinking. Main enemies are mutants and human raiders.