Cutting elements include a substrate, a polycrystalline table, and an asymmetric interface feature. The interface feature includes a shape that is reflectively asymmetric about at least two planes defined by x, y, and z axes of a Cartesian coordinate system defined to align a z axis of the coordinate system with the central axis of the substrate and to locate a center of the coordinate system at a midpoint along an axial height of the asymmetric interface feature. Methods of forming a cutting element involve: forming an asymmetric interface feature at an end of a substrate; distributing a plurality of superhard particles on the substrate over the asymmetric interface feature in a mold; and bonding the superhard particles in the mold to form a polycrystalline table attached to the substrate.