The present invention relates to an anti-whiplash system for the use in vehicle seats. The inventive anti-whiplash system for the use in vehicle seats comprises a head restraint (1) mounted on the backrest of a vehicle seat, wherein the head restraint (1) comprises a release mechanism for reducing the gap between an occupant's head and the head restraint in case of an accident, said release mechanism comprises a movable part (5) and a stationary part (3), wherein a clearance between the movable part (5) and the stationary part (3) opens up when the release mechanism is released, characterized in that a wedging body (4) is provided having a small width portion and a large width portion and an intermediate increasing width portion, wherein the wedging body (4) points with its small width portion towards the clearance between the movable part (5) and the stationary part (3), and in that the wedging body (4) is movable and preloaded to move into the clearance as it opens up to thereby abut against the movable part (5) and against the stationary part (3) in order to prevent the movable part (5) of the head restraint (1) from moving back.