A common side effect of a narcissistic pathological relationship is disordered eating. Because narcissists, sociopaths and anti-social behavior disordered people use hot and cold or sometimes called mean and sweet cycles to disorient you and make you feel insecure, the body reacts by putting you into fight or flight syndrome.
For example: You may diet when the narcissist is being nice and then eat when he ignores you. This ensures your body is constantly confused about how to protect you. Disordered eating can carry on long after the relationship ends because most narcissists leave you suddenly and you are left without closure. It keeps you feeling on edge and waiting for him to contact you again. A common thing for women to do in the aftermath of a narcissistic relationship is to try to get a ‘revenge body.’