Fat freezing or liposuction, and what decides which one suits you

Fat freezing is one of the clinic's treatments, described on our fat freezing treatment page. Liposuction is described here from published studies and from the patient pages of the American Society of Plastic Surgeons, which we call the society from here on.

What fat freezing and liposuction each do to the fat under your skin

Fat freezing, which doctors call cryolipolysis, cools a pocket of fat from outside the skin. The American Society of Plastic Surgeons' page on cryolipolysis explains that fat cells are particularly sensitive to cold, unlike other cells. The cooling injures the fat cells while the skin and other structures are spared. The body then clears the injured cells gradually.

How much does the fat layer shrink? In a 2020 study of 231 Asian patients and 448 treated areas, the fat layer was 19.2% thinner on a pinch test and 22.8% thinner on ultrasound. A 2025 pooled analysis of 30 studies and 3,158 people found abdominal circumference down by 3.56 cm on average, in the 211 people whose studies measured it.

Liposuction removes fat by suction, in an operation. A 2017 review of the evidence on liposuction describes it as suction-assisted body contouring surgery. Fluid with a local anaesthetic is infiltrated into the area (the tumescent phase), and the fat is then suctioned out. The review also covers the checks made before the operation, energy-assisted forms of the procedure and possible complications.

How fat freezing and liposuction compare, and where the studies we reviewed are silent

None of the studies reviewed for this article sets the two against each other directly, so no study here shows which works better. Both are described for fat that has persisted despite diet and exercise, each with its own conditions, and the choice starts with an examination. The table sets them side by side.

How each one is done, and what you may feel during and after

The society's cryolipolysis page describes a session, set out below in four steps, and says it is done without anaesthesia.

Dr Samantha describes one cycle in her own words.

“Each cycle, 35 minutes. So you apply. After 35 minutes, you remove. Then you're going to massage it in. Then you move on to the next area.” Dr Samantha Tay

The society's page says the massage may help. The clinic's own fat freezing page puts it more carefully: whether the massage improves the final result is not settled in the published evidence.

Afterwards, the society's page says there are no activity restrictions, and that the area may feel sore, as if after a workout. Numbness, redness and swelling are also reported; the rates found in studies are in the side effects section below.

Liposuction is done as an operation, with an anaesthetic. The society's page on the risks of liposuction says the risks can include bruising, swelling and a change in skin sensation that may persist. The full list is in the risks section below.

Which kind of fat suits fat freezing, and which suits liposuction

The society's patient pages describe who each one usually suits, and the cryolipolysis page also says who should not have fat freezing. That page and the society's page on who is a good candidate for liposuction say, in their own terms:

Neither page gives an amount of fat that suits one or the other. How much fat there is, where it sits and how the skin over it behaves are judged at the examination.

Nexus adds to the society's list. Fat freezing waits during pregnancy or breastfeeding, and it is not done after recent abdominal surgery or over a hernia where the applicator would sit. The clinic's fat freezing page also points people with a BMI of 30 or more towards weight loss as the first step.

Why loose skin changes the choice between the two treatments

Loose skin matters for both. The society's cryolipolysis page says people with loose skin or poor tone may not be suitable. For liposuction, its candidate page describes firm, elastic skin. Its risk page lists rippling or loose skin, and says further procedures are sometimes recommended to reduce excess skin.

So the doctor first works out which change is the main one. Our article on whether a double chin is fat, loose skin or jaw shape works through the same question for the face. Where loose skin is the main change, options aimed at the skin itself, such as HIFU treatment, are a separate conversation.

What the studies report about side effects and risks of fat freezing

Fat freezing research has largely been done in Caucasian patients. A 2019 review of fat freezing in Asian patients found four trials run entirely in Asian patients. They reported mild, short-lived side effects, such as redness, a haematoma (a bruise-like collection of blood), numbness and pain, and no changes in skin colour.

The 2025 pooled analysis, of 30 studies, gives these rates: numbness 49.5%, redness 44.5%, swelling 30.5%, pain 28.8%, sensitivity 25.4%, tingling 15.2% and darker skin patches 2%. Its authors call this a relatively high level of minor side effects.

The rare complication in which the treated fat grows

Paradoxical adipose hyperplasia (PAH) is a rare complication in which the treated pocket grows instead of shrinking. A 2025 pooled analysis of 28 studies and 13,078 patients found it in 0.22% of patients, about 1 in 455 (95% confidence interval 0.10% to 0.47%). It rated the evidence as low certainty, and its authors add that this appears higher than manufacturer reports.

Reports differ on who is at risk. The society's cryolipolysis page says PAH is three times more likely in men than in women and is seen more in people of Hispanic or Latino descent. The pooled analysis, by contrast, found the difference between men and women not statistically significant. The studies reviewed for this article give no rate for Asian patients.

Correcting PAH means surgery. The clinic's fat freezing page names liposuction for it.

What the surgeons' society lists as the risks of liposuction

The society's risk page says liposuction risks can include the ones below, but it gives no rates. The table sets each one beside the fat freezing risks in the sources.

The society adds that special considerations apply when large amounts, usually more than five litres of fat, are suctioned. The two columns come from different sources and different kinds of evidence, so they are not a ranking of one against the other.

What happens to the treated area if your weight changes later

Whether treated fat comes back is not settled, and the evidence is thin on both sides.

In a randomised trial of 32 non-obese women, 14 of whom had small-volume liposuction, the thigh region was still reduced at one year. Body fat overall, though, had been restored, and had shifted from the thigh to the abdomen. The women had agreed not to change their lifestyle during the study.

For fat freezing, the longest follow-up we found is two people photographed years after treatment, with their untreated side for comparison. Two people are too few to generalise from, and we found no study that measured whether fat returns elsewhere in the body after fat freezing.

The summaries of these studies do not report what a large gain or loss of weight does to a treated area, so it is worth raising at the consultation.

Why neither fat freezing nor liposuction is a weight-loss treatment

Both are described for a local area of fat, not for weight overall. The society's cryolipolysis page speaks of a localised bulge of fat, and its candidate page describes liposuction for adults whose weight is no more than 30% from their ideal.

If your main concern is your weight overall, the clinic's medical weight loss programme is a separate route, and it starts with a medical workup.

Questions worth asking any doctor before you choose either one

The useful first question is whether fat, loose skin or muscle is the main change, and an examination answers it. After that, these questions are worth asking any doctor, a surgeon included.

If you are weighing the two for a pocket of fat, our cryolipolysis treatment page explains how fat freezing is done at the clinic. The choice is made at a consultation, after the doctor has examined you.