More and more moles: how is that possible?

Moles mainly appear during childhood or adolescence, but can actually occur at any age. So it is possible that you notice more and more moles as you get older. Why is that? And are they harmless or potentially dangerous?

Also read: White spots on the skin: what types are there?

How do moles appear?

A mole, or nevus, is a small patch of skin that contains a higher concentration of melanocytes. Melanocytes are the cells responsible for producing skin pigments called melanin.

They begin to appear in childhood. Once formed, moles never disappear, but may become lighter, darker, raised or fleshier.

Why do moles suddenly appear?

• A small mole that grows. Moles that appear during childhood often grow in proportion to the growth of the body. They can also darken with age. In some people, moles continue to develop throughout their lives. So it is possible for small moles—ones you never noticed before—to grow so large that they catch your attention overnight.
• UV rays: UV rays from the sun or tanning beds are a common cause of the sudden appearance of moles. When exposed to UV light, melanocytes produce melanin (a protective pigment that darkens the skin) and clump together to form moles. This phenomenon mainly affects people with fair skin. After a prolonged period of exposure to the sun, you may notice that new moles have formed or that existing moles have darkened.
• Hormonal changes: During periods when your hormones are very active (adolescence, pregnancy), moles can appear (almost) overnight. This is because estrogen stimulates the activity of melanocytes. This can lead to increased melanin production and possibly to the appearance of new moles or the darkening of existing ones.
• Seborrheic keratoses: Seborrheic keratoses (also called seborrheic warts or age spots) are often confused with moles. They appear from the age of 30, but are more common in people over 50. The older you get, the more they appear. At first, they are flesh-colored or light brown. Then they darken and look more and more like moles.
• Medication: Certain medications can change the appearance of (existing) moles overnight. This is the case with hormonal drugs and immunosuppressants. Other drugs are photosensitizing and can increase the skin's sensitivity to the sun and indirectly affect the melanocytes. This is the case with certain antibiotics, non-steroidal anti-inflammatory drugs (ibuprofen), antidepressants, antifungals, etc.

Also read: Types of pigment spots: white, brown and red spots on the skin

When should I be concerned about new moles?

Although most moles are benign, a small percentage can become cancerous over time. New moles that appear in adults are more likely to become cancerous than old ones. A 2017 case study found that 70.9% of melanomas originate from a new mole.

If you are an adult and see a new mole, you can have it examined by your family doctor or a dermatologist. Also see a specialist if you notice changes in existing moles or the appearance of an unusual spot.

It is advisable to have your skin checked by a dermatologist every year.

Also read: Check yourself for skin cancer: what should you look out for?

Can moles disappear?

Moles can disappear, but rarely overnight. The process is usually gradual. This is a result of aging. In general, there is no cause for concern.

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