Disclosed is a mattress for supporting a reclining body with low body pressure and in alignment. The mattress, extends in a lateral direction from side to side and extends in a longitudinal direction from a mattress head to a mattress foot where the mattress includes a head part, a shoulder part, a waist part, a hip part and a leg part. The reclining body has a displacement profile that causes the mattress to undergo differing vertical displacements when supporting the reclining body. The mattress core has displacement parameters established by internal contour interfaces varying to match the displacement profile of the reclining body while supporting the reclining body with low body pressure. The core has a plurality of regions where the vertical displacement in one or more of the regions varies to match the displacement profile of the reclining body to maintain the reclining body in alignment.