Whiteheads are small white spots (about the size of pinheads) which are caused by collections of oil and skin in pores. Whiteheads are follicles that are filled with plugs of sebum and sloughed off cells, but have only a microscopic opening to the skin surface. Since the air cannot reach the follicle, the material remains white. Whiteheads can be more numerous on the face and shoulders than red bumps filled with pus. Good consistent skin hygiene can help improve this condition.