Become lonely and perceive stress more strongly than social people
Loneliness can cause disturbances in your natural sleep cycle
Loneliness and depression often go hand-in-hand
Your defenses aren't "up" so you tend to have a suppressed immune system
It affects your ability to socially interact
Hermits express negatively more severely
Decreases your life span, stresses your heart, circulatory system, respiratory system, digestive system, mental health and the way people see you
Pulling away from society on occasion can be refreshing. Pulling away entirely for good? Not so much.