Cryolipolysis is a medical treatment used to destroy fat cells. Its principle relies on controlled cooling to near 4° Celsius (approx. 39° Fahrenheit) for the non-invasive localized reduction of fat deposits in order to reshape body contours. The exposure to cooling is set so that it causes cell death of subcutaneous fat tissue without apparent damage to the overlying skin. The procedure is billed as a nonsurgical alternative to liposuction. "Cryolipolysis" is a portmanteau of "cryogenic" and "lipolysis". Generically the process can also be known as "fat freezing".