Borderline Personality Disorder (BPD) is widely understood as a condition of profound emotional and psychological instability — a disorder that disrupts relationships, identity, and the capacity for self-regulation. What is far less widely appreciated, however, is the degree to which BPD is also a disorder of the body. Beneath the clinical surface of emotional dysregulation lies a measurable, multi-system biological crisis rooted in chronic stress exposure, early adversity, and accelerated physiological deterioration. Two theoretical frameworks are increasingly central to understanding this phenomenon: the concept of Allostatic Load (AL) and the evolutionary model known as the Pace-of-Life Syndrome (PoLS). Together, these…