As you age, years of being in the sun start to add up. Age spots (also called liver spots or solar lentigo) are collections of pigment caused by exposure to the sun. Pigment is deposited as a response to injury, just like a scar is a response to a cut. The pigment collects in areas injured because of thin skin or greater sun exposure. Age spots also can be caused by bruising that leaves blood pigment behind. They are most common in people older than 55. The spots commonly appear on the hands, but they can be almost anywhere, especially sun-exposed areas, such as the face, back, arms, feet and shoulders.