A communications cable having a plurality of twisted pairs of conductors and various embodiments of a metal foil tapes between the twisted pairs and a cable jacket is disclosed. In some embodiments, a metal foil tape includes a discontinuous metal layer and a polymer layer bonded to the metal layer. Portions of the metal layer and the polymer layer are deformed to form a plurality of dimples, the dimples forming air gaps between the polymer layer and the cable core or a barrier layer if used. The air gaps lower the overall dielectric constant between the metal layer and the cable core, thereby lowering the alien capacitance of the communications cable.