Raze_Larian: In BD you need food and water to sleep, and a place to sleep in order to eat/drink much (so it is more like a combined rest period). I don't recall if there is much you can eat/drink without sleeping (besides a few special food items), since after the beginning of the game I rarely ate or slept.

There are a couple bedrolls to be found in the game (the first on the second level, after you jump down the pit in the arena), which will let you sleep/eat anywhere (IIRC if there are no opponents in the immediate area).

In DD I used food and sleep for longer before switching to pretty much just potions, but in BD there is health and mana regeneration, which effectively eliminates (once you get up a couple levels) the need for the small boosts to health and mana that eating provided in DD.