BACKGROUND Liposuction is one of the most frequently performed cosmetic procedures in the United States, but its cost and downtime has led to the development of noninvasive approaches for adipose tissue reduction. OBJECTIVE To determine whether noninvasive controlled and selective destruction of fat cells (Cryolipolysis) can selectively damage subcutaneous fat without causing damage to the overlying skin or rise in lipid levels. METHODS Three Yucatan pigs underwent Cryolipolysis at 22 sites: 20 at cooling intensity factor (CIF) index 24.5 (-43.8 mW/cm2), one at CIF 24.9 (-44.7 mW/cm2), and one at CIF 25.4 (-45.6 mW/cm2). Treated areas were evaluated using photography, ultrasound, and gross and microscopic pathology. Lipids were at various times points. One additional pig underwent Cryolipolysis at various days before euthanasia. RESULTS The treatments resulted in a significant reduction in the superficial fat layer without damage to the overlying skin. An inflammatory response triggered by cold-induced apoptosis of adipocytes preceded the reduction in the fat layer. Evaluation of lipids over a 3-month period following treatment demonstrated that cholesterol and triglyceride values remained normal. CONCLUSIONS Cryolipolysis is worthy of further study because it has been shown to significantly decrease subcutaneous fat and change body contour without causing damage to the overlying skin and surrounding structures or deleterious changes in blood lipids. The research was funded by Zeltiq Aesthetics. Drs. Brian Zelickson, Barbara Egbert, and Robert Rhoades are paid consultants to Zeltiq. Dr. Dieter Manstein receives royalty payments from Zeltiq related to licensing of the Cryolipolysis technology. Dr. Jessica Preciado, Dr. John Allison, and Kevin Springer are employees of Zeltiq Aesthetics.