Is lentigo (brown spots on your legs) harmful? i have only three spots.

Lentigo: A lentigo or solar lentigo is one of the most common growths that occur on the skin. In general terms these are often referred to as liver spots or age spots. Lentigo are most frequently seen in adults over thirty, and they occur most commonly on sun exposed skin, face, back of hands, arms, chest and lower legs. They are typically tan or brown in color, and are generally flat.