A mole, medically known as a melanocytic nevus, is a common skin growth that develops when pigment-producing cells, called melanocytes, cluster together. These cells create the melanin that gives skin its color. Nearly every person has moles, and it is normal for these spots to appear and change in size, shape, or color over a lifetime. Understanding the difference between a normal, benign change and a concerning one is important for skin health awareness.
The Typical Development of Moles
Most acquired moles appear during childhood and adolescence, typically between the ages of 10 and 30. They often begin as flat, small spots (junctional nevi) that are uniform in color with smooth, round borders. Moles may grow proportionally as a child develops, which is an expected change.
During puberty, hormonal fluctuations can cause existing moles to darken or slightly enlarge. The number of moles generally peaks in early to mid-adulthood, with most people having between 10 and 40 moles. Growth usually stops by the early twenties, and new moles appearing after age 30 should be monitored closely.
Normal Changes Associated with Aging
As a person moves into mid-adulthood and senior years, moles often undergo involution, a normal part of their lifecycle. Pigment cells may migrate deeper into the dermis, causing the mole to change from a flat spot to a raised, dome-shaped bump (intradermal nevus). These raised moles may lose their dark pigmentation entirely, becoming flesh-colored or paler over time.
Moles may also flatten out or even disappear completely, a process that is usually gradual and harmless. This fading can sometimes be preceded by a pale ring around the mole, known as a halo nevus. It is also common for older, raised moles to develop coarse hairs, which is not a sign of abnormality. These age-related changes are typically slow and symmetrical, differentiating them from rapid, asymmetrical changes that may signal a problem.
Warning Signs of Abnormal Mole Growth
Rapid or irregular changes in a mole’s appearance can signal melanoma, a serious form of skin cancer. The ABCDE rule is the most widely used framework for identifying potentially dangerous moles, focusing on five key characteristics. This systematic approach helps identify lesions changing differently than other spots on the body, sometimes called the “ugly duckling” sign.
The ABCDE Rule
- Asymmetry: One half of the mole does not match the other half in shape or appearance.
- Border: The border becomes irregular, notched, or blurred, unlike the smooth, defined border of a normal mole.
- Color: A suspicious mole may exhibit multiple colors (such as tan, brown, black, red, white, or blue) instead of one consistent shade.
- Diameter: Melanomas are often larger than six millimeters, which is roughly the size of a pencil eraser.
- Evolution: This refers to any change in a mole’s size, shape, color, or height over a short period.
Other symptoms that warrant immediate professional evaluation include a mole that begins to itch, bleed, crust, or spontaneously open into a sore.
Practical Guide to Monitoring Moles
Regular self-examination is the most effective way to monitor moles and detect concerning changes early. Dermatologists recommend performing a thorough check of your entire body once a month to establish a baseline and notice any new or evolving lesions. This examination should be done in a well-lit room, using a full-length mirror and a hand-held mirror to see hard-to-reach areas.
It is important to check the entire skin surface, including the scalp, palms of the hands, soles of the feet, and between the toes. Taking photographs of existing moles can be a helpful way to track subtle changes over time. If you find any mole that fits the ABCDE criteria or notice a new growth after the age of 30, schedule an appointment with a dermatologist promptly. Individuals with a high number of moles, a personal or family history of melanoma, or a weakened immune system should also consider regular professional skin checks.