Health Dictionary
Reliable, easy-to-read patient information on common medical conditions — written in plain language, free of jargon, and grounded in current evidence. Browse the most frequent diagnoses, understand what they mean for everyday life, and learn which steps and questions help you have a focused conversation with your doctor.
Moles
Introduction
Overview
Overview
Moles are growths on the skin. They happen when cells in the skin, called melanocytes, grow in a cluster with the surrounding tissue. Moles are very common. Most people have between 10 and 40 moles. A person may develop new moles from time to time, usually until about the age of 40.
Moles are usually pink, tan or brown. They can be flat or raised. They are usually round or oval and no larger than a pencil eraser.
About one out of every ten people has at least one unusual (or atypical) mole that looks different from an ordinary mole. The medical term for these unusual moles is dysplastic nevi. They may be more likely than ordinary moles to develop into melanoma, a type of skin cancer. Because of this, you should have a healthcare professional check your moles if they look unusual, grow larger, change in color or outline, or in any other way.
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Raviteja Guddeti, M.B.B.S. [2]