To anyone with “molechondria,” the question of how long it takes for a normal mole to develop is often on their mind.

One-third of melanoma cases arise from pre-existing moles. Of course, any new mole can trigger anxiety, especially in people over 40.

Growth Cycle of the Common Skin Mole

“We don’t really have a way to determine when the process of a mole starts, since we can only detect it once it becomes visible to the naked eye,” says Caroline A. Chang, MD, clinical assistant professor of dermatology at Alpert Medical School of Brown University, and a board certified cosmetic and medical dermatologist with Dermatology Professionals, Inc.

Dr. Chang continues, “Once the mole appears on the skin, it should not grow or change significantly in size.”

If a mole appears larger than usual, this doesn’t always mean it has grown—i.e., more pigmented cells.

“Moles can become slightly larger when someone’s skin stretches (e.g., pregnancy, weight gain or growth for example in children),” says Dr. Chang.

A normal mole grows, as far as new pigmented cells, very slowly. Watching it from month to month will make it difficult to detect an increase in size if it is still growing.

After a year of not watching it, though, you may be able to detect a very slight increase in size. A new mole will grow in size but eventually will cease growing.

Middle-aged people can get new moles, which, of course, begin as pinpoints to the naked eye and may not be really noticed until they have grown (slowly) to one millimeter. moles grow

New moles in middle-aged people can also remain benign for the rest of their life, but they should always be inspected by a dermatologist.

What makes the mole eventually stop growing?
Dr. Chang explains, “Benign moles are an organized structure. They appear as they are and don’t change much. Normal genetics in the mole keep the mole from growing larger.”

There are exceptions, of course, as we have all seen people with a gigantic mole on the back of their leg or even on their face, for instance.

Moles larger than pencil eraser diameter should be monitored closely, but most will not turn into melanoma.

dr. chang

Dr. Chang practices general and cosmetic dermatology and has a special focus on melanoma and the use of dermoscopy for mole monitoring.