The Science of CoolSculpting

An Overview of How CoolSulpting Kills Fat Cells

Step 0: Resistant Fat

Resistant Adipose

Resistant fat is the fat that resists the efforts of diet and exercise. As other parts of the body become more lean, these areas do not. Worse, areas become more resistant with age.

Resistant fat is located between the skin and underlying muscle. The specific region is determine by genetics and hormones. Men tend to have resistant fat along the belt line. Female patterns include hips, thighs, bra bulge, etc.

The number of fat cells in our bodies is essentially determined at puberty. Prior to puberty, weight gain results in the multiplication of fat cells. After puberty, the fat cells grow and shrink in size, while the number of fat cells remains relatively constant.

Step 1: Treatment

Treated Adipose

A CoolSculpting treatment carefully chills a volume of tissue. Fat inside the fat cells congeals and forms crystals. This process is similar as how olive oil congeals when stored in a refrigerator. The fat crystals fatally wound fat cells.

The CoolSculpting chilling process is very specific and controlled. As such, fat is able to congeal before water can freeze. Since water does not freeze, CoolSculpting does not cause the formation of ice crystals. As such, CoolSculpting can specifically target fat cells without harming nerve, muscle and skin cells.

Step 2: Dying Fat Cells

Dying Adipose

The wounded adipose dies within three days of treatment. This death process is termed apoptosis. Apoptosis causes the cells digest themselves.

The immune system eliminates the dead tissue by eating it. The dead tissue is used by the body as a source of fuel. The elimination process is slow and can take several months. Since the elimination process is slow, there is no clinically significant increase in serum cholesterol or other abnormal lipid profiles.

Step 3: Persistent Results

Long Lasting
Reduction of Adipose

CoolSculpting results are long lasting. CoolSculpting treatment actually kills fat cells. Adult fat cells regenerate at a rate of about 1% per year. Because of this slow rate of regeneration, CoolSculpting results persist for decades.

Because the results persist, you want to use a clinic that provides esthetic results. Our link to the art of CoolSculpting explains the treatment philosophy at Medical Spa NW.

The Story of CoolSculpting

FDA Clearance

CoolSculpting is based upon solid science. Carefully chilling tissue kills just the fat cells. Skin, nerve and other tissues are unharmed. The medical term for this process is cryolipolysis. Cryolipolysis is safely performed with CoolSculpting®, a patented1 medical device.

CoolSculpting was cleared in Canada and Europe in 2009. It received FDA clearance as a class 2 medical device in 2010. At the time of this post, there have been over 4 million treatments performed. This makes CoolSculpting the world's most popular noninvasive fat reduction procedure.

It started with a Popsicle

It started with a Popsicle

The idea for CoolSculpting came from two medical studies. A study from 1970, titled Popsicle Panniculitis2, investigated the formation of new dimples in the cheeks of toddlers. It was determined that parents had treated teething pain with an orally placed frozen Popsicle®. The prolonged exposure to cold resulted in the death of just fat cells in their cheeks, forming new dimples. There was no harm to the inner lining of the mouth or damage to the tongue. Since fat cells readily multiply prior to puberty, the dimples filled in over time.

It also started with frozen saddles

A study from 1980, titled Equestrian Cold Panniculitis3, investigated permanent, disfiguring fat loss on the inner thighs of women. It was determined that these women went horseback riding in the winter upon frozen saddles. The prolonged exposure to cold killed just fat cells on their inner thighs. The cold did not affect skin, nerve or other tissues. Since the fat loss occurred after puberty, the authors hypothesized that the fat loss was permanent.

Development of CoolSculpting as a Medical Device

The development of CoolSculpting as a medical device was a significant undertaking. The concept of using cryolipolysis as a fat reduction procedure was entirely novel. To assure safety, the FDA required investigational trials on animals before testing on humans.

The animal study used pigs4. CoolSculpting was performed on the back of the pigs on specific days prior to tissue collection. This allowed the progress of treatment to be monitored.

Summarizing the pig results, on the day of treatment, there were no tissue changes at all. Several weeks after treatment, the immune system had infiltrated the treatment area. By three months, the immune system had vacated the treatment area. The final result showed a significant reduction of fat cells, with no impact to skin, nerve or other tissue types.

With the success of the pig study, the FDA was able to authorize an investigation trial of CoolSculpting on humans5. This trial was limited to abdominal tissue that was scheduled to be surgically removed from an elective panoplasty. A panoplasty is commonly referred to as a tummy tuck. The outcome of the human study essentially replicated safety and efficacy of the animal study.

Cryolipolysis: How Cold Kills Fat Cells

Human studies show that CoolSculpting triggers apoptosis in fat cells. Apoptosis is a highly regulated process where a cell kills itself by creating digestive enzymes. Tissue examination shows that apoptosis is limited to just the fat cells. Apoptosis does not occur in skin, nerve or other tissue types. This explains how CoolSculpting is able to kill just fat cells without affecting other cells.

Exactly why apoptosis is limited to just fat cells is not entirely understood. The working model is the cryolipolysis selectively damages the membrane of fat cells. Fat cells contain mostly fat, while other cell types contain mostly water. CoolSculpting is able to crystallize the fat in a fat cell without freezing water in other cell types. Since the crystals being formed are just inside the fat cells, only the fat cells experience membrane damage triggering apoptosis.

This selective membrane damage model explains a clinical observation. Massaging tissue immediately after treatment kills another 68% of fat cells6. Clearly, mechanical damage is involved with triggering apoptosis.

CoolSculpting Results Are Long Lasting

CoolSculpting results are also long lasting*. The first people to undergo CoolSculpting were test subjects treated in 2007. A follow-up study7 at 6 and 9 years post treatment demonstrates that the reduction of fat continues to persist. The persistence of results is because CoolSculpting kills fat cells and fat cells have only a very limited ability to regenerate in adults.


1 US Patent #9,308,120 details CoolSculpting

2 Epstein EH Jr, Oren ME. “Popsicle Panniculitis,” N Engl J Med. 1970 Apr 23;282(17):966-7

3 Beacham BE, Cooper PH, Buchanan CS, Weary PE. “Equestrian Cold Panniculitis.” Arch Dermatol. 1980 Sep;116(9):1025-7.

4 Zelickson B, Egbert BM, Preciado J, Allison J, Springer K, Rhoades RW, Manstein D. “Cryolipolysis for noninvasive fat cell destruction: initial results from a pig model.” Dermatol Surg. 2009 Oct;35(10):1462-70.

5 Coleman SR, Sachdeva K, Egbert BM, Preciado J, Allison J. “Clinical efficacy of noninvasive cryolipolysis and its effects on peripheral nerves.” Aesthetic Plast Surg. 2009 Jul;33(4):482-8.

6 Boey GE, Wasilenchuk JL. “Enhanced clinical outcome with manual massage following cryolipolysis treatment: a 4-month study of safety and efficacy.” Lasers Surg Med. 2014 Jan;46(1):20-6

7 Bernstein EF. “Long-term efficacy follow-up on two cryolipolysis case studies: 6 and 9 years post-treatment.” J Cosmet Dermatol. 2016 Jun 23.

*Results and patient experience may vary
Follow this link for Clinical Studies