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Why do we have moles on our skin? © iStock

Why do we have moles on our skin?

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Before you ask how to remove moles, you might want to find out why we have them, and you'll be surprised to find out how many we actually have.

Asked by: Richard House, North Yorkshire

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During the first 12 weeks of pregnancy, the developing foetus is making melanocytes – the skin cells that produce ordinary skin colour. These aren’t always evenly spread out: random areas will acquire a cluster and during your life, these clusters can grow into a mole.

Moles are quite different from freckles. Almost everyone has from 30 to 60 moles on their body, but freckles only occur in people with certain genes – particularly the one responsible for red hair. Freckles also need sunlight to trigger them, while moles appear spontaneously.


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Authors

luis villazon
Luis VillazonQ&A expert

Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.

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