What causes benign fatty lumps to develop?

Doctors do not know what causes benign fatty lumps, known as lipomas, as of 2015, notes Mayo Clinic. They believe that genetic factors contribute to the development of lipomas, as people with family members who have the fatty masses are at higher risk.

Lipomas are harmless in most cases, and usually do not require medical treatment, states Mayo Clinic. Lipomas generally appear in those who are middle-aged, and some people develop multiple lipomas. People may choose to have lipomas removed if they are painful or become larger. While they may suspect they have lipomas, people who discover lumps anywhere on their bodies should have them examined by doctors.