Bulimia nervosa is an eating disorder characterized by binge eating followed by purging, either through vomiting or laxative use. The exact causes are unknown but include genetic, environmental, psychological, and cultural factors. Signs and symptoms include depression, anxiety, irregular heartbeat, and issues with bowel functioning. Effects involve physical harm like oral trauma and infertility as well as mental issues like low self-esteem. It is important to seek help from professionals and offer social support to combat stigma.