Age spots are brown-black in color, with diameters ranging from 1 mm to 10 mm. They vary in size, with large spots up to 2-3 cm in diameter. Most of them do not protrude above the skin, but some large spots (moles) can also protrude above the skin and are flat. They are composed of lipofuscin pigments and are prone to occur on the face, back of the hands, calves, back of the feet, trunk and other exposed skin of the elderly. People usually call them "longevity spots", and in medicine they are called senile pigment spots (moles). Age spots not only exist on the skin, but can also appear in the heart, blood vessels, liver and endocrine glands, affecting the normal functions of various organs. Therefore, age spots should not be taken lightly.