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A skin mole is caused by the clustering of skin cells. You are actually born with all the moles you will have--when you were born, they just were not visible yet. A mole will darken with age, and can also grow. There are two reasons for mole growth. The first is age. The second reason a mole grows is due to sun exposure. That, thankfully, can be prevented, and the mole growth stopped.

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Apply lotion with at least SPF 15 on your face and body on a daily basis. You will undoubtedly be in the sun for a few minutes every day, and this lotion will help protect your skin.

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Cover your skin with long clothing and wear hats when outside. This will help protect your skin from sun exposure, which can result in the growth of both old and new moles.

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Use sunscreen when at the beach or pool. An SPF rating of 30 or more is recommended. Reapply the lotion every hour you are outside.

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Avoid direct sunlight. Sunlight, even in winter, can cause the moles on your skin to grow. If you want to have a tan, use self-tanning lotion or have a spray tan applied.

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Skip the tanning beds. This is one of the quickest ways for moles to appear and grow on your body, due to the concentrated UV light emanating from the bulbs.