1. A method of analyzing an external body condition using a three-dimensional facial image, the method comprising: providing a computer system, wherein the computer system comprises a computer-readable medium containing instructions for execution by at least one processor; constructing a three-dimensional facial image based on at least one captured image of a subject's face, wherein the at least one captured image reflects at least one external body condition; processing the three-dimensional facial image to enable a beauty analysis; analyzing the at least one external body condition via the three-dimensional facial image; selecting a beauty product for affecting the at least one external body condition based on the analyzing; and displaying, on a display device, simulated effect of the beauty product on the external body condition via the three-dimensional facial image.