If you are weighing up fat freezing against weight loss injections, most of what you read will be trying to sell you one or the other. We should be upfront: My Fat Freeze offers fat freezing and does not offer Mounjaro or Wegovy, so we have an obvious interest here. We have tried to give you a fair account anyway, including where the injections are plainly the stronger option.
The short version is that these treatments do different jobs. Mounjaro and Wegovy are prescription medicines that lower your overall body weight, often by a lot. Fat freezing, or cryolipolysis, is a cosmetic treatment that reduces a pocket of fat in an area you choose. It is not a weight loss treatment, and most people see little change on the scales.
| Fat freezing | Mounjaro and Wegovy | |
|---|---|---|
| What it is | Non-invasive cosmetic procedure | Prescription medicine, injected weekly |
| What it changes | Fat in the treated area | Appetite and overall body weight |
| Average result | Around 20 to 25% of the fat layer in each treated area | Around 15% of body weight (Wegovy), up to 22.5% (Mounjaro, highest dose) |
| Choose the area? | Yes | No |
| Wider health benefits | None shown | Yes, see below |
| Commitment | Usually 1 to 3 sessions per area | Ongoing: results depend on staying on it |
| Usually suits | People near their target weight with pinchable fat | People with a higher BMI, often with weight-related health conditions |
How well does each one work?
There is no contest on overall weight loss, and it would be dishonest to suggest otherwise. In the main Mounjaro trial, SURMOUNT-1, 2,539 adults lost an average of 16% of their body weight on the 5 mg dose and 22.5% on the 15 mg dose over 72 weeks, against 2.4% on placebo. In STEP 1, people on Wegovy lost an average of 14.9% over 68 weeks, against 2.4% on placebo.
The benefits can go beyond the mirror too. In the SELECT trial, semaglutide, the medicine in Wegovy, cut major heart events by 20% in people with established cardiovascular disease and overweight or obesity. No cosmetic treatment can claim anything like that.
Fat freezing is measured differently, and the numbers should not be read side by side. Published reviews generally report a reduction of around 20 to 25% in the thickness of the fat layer in the treated area, not 20 to 25% of your body. A 2025 analysis of 30 trials and 3,158 people found an average waist reduction of 3.56 cm. Changes appear gradually, usually from 6 to 12 weeks, with the final result at around 3 to 4 months.
It also has clear limits. It only reaches fat you can pinch, not the deeper visceral fat around your organs, and studies have found no significant effect on cholesterol or liver function. Much of the research also used one branded system, CoolSculpting, and not every machine has been studied to the same degree. Whoever you see, it is fair to ask which device they use.
What does each one cost?
Privately, Mounjaro typically costs from about £180 to £449 a month depending on dose and provider, with one published estimate putting the first year at £2,640 to £3,020. Wegovy costs about £169 to £289 a month at the standard maintenance dose, or roughly £2,140 for the first year. These costs carry on for as long as you take the medicine, and prices have moved sharply in the past.
The NHS is far cheaper, at £9.90 per prescription item in England and free in Scotland, Wales and Northern Ireland, but access is tightly limited. Around 3.4 million people in England are eligible for Mounjaro under NICE guidance, and the phased rollout aims to treat 220,000 in its first three years. On the NHS, Wegovy is available only through specialist weight management services, for a maximum of two years.
Fat freezing is a cost you pay per treatment and then stops. At the time of writing, our listed prices run from £119 for one area to £239 for four, so two sessions on two areas would come to £318. Prices vary widely across the UK, and a year of treatment elsewhere can run from £600 to more than £3,000.
Fat freezing often works out cheaper, but that is only a fair comparison if it does what you need. If you have a lot of weight to lose, the medicine is doing something fat freezing simply cannot, and the cheaper option is not the better value.
What are the risks?
Weight loss injections. Stomach and bowel side effects are the most common. Nausea affected around 31% of people on the top dose of Mounjaro and around 44% on Wegovy in trials, alongside diarrhoea, vomiting and constipation. These are usually mild to moderate and tend to ease once the dose settles. Rarer but more serious risks include pancreatitis and gallbladder problems, and the medicines are not suitable during pregnancy or for anyone with a personal or family history of medullary thyroid cancer.
Fast weight loss brings its own changes. In SURMOUNT-1 body composition data, about a quarter of the weight lost was lean mass, including muscle. Some people also notice loose skin, temporary hair shedding or a thinner-looking face. This is sometimes called “Ozempic face”, though it is caused by rapid weight loss itself, not by the medicine directly.
There is a separate risk from the illegal market. The MHRA has warned about counterfeit Mounjaro pens, and in 2025 it shut down an illicit manufacturing site in Northampton. That is no reflection on the genuine medicines, but it is a good reason to use only a registered UK prescriber and pharmacy, and never a salon or a social media seller.
Fat freezing. It acts on one area rather than through your whole body, but it is not risk free, and it is not painless. Expect intense cold and suction at first, with discomfort that usually eases after about 10 minutes as the area numbs. Afterwards, temporary numbness, redness and swelling are common, affecting around 49.5%, 44.5% and 30.5% of people in the same 2025 analysis, along with bruising and tingling. Most people return to normal activities straight away.
The complication you should know about is paradoxical adipose hyperplasia (PAH), where the treated fat grows firmer and larger instead of shrinking, usually appearing 2 to 4 months later. It is not dangerous to your health, but it does not go away by itself and usually needs liposuction to correct. Estimates vary, and a 2025 review of 13,078 patients put it at 0.22%, or about 1 in 455 people, which is higher than manufacturers originally reported. Fat freezing is also unsuitable for people with cold-related conditions such as cold urticaria or cryoglobulinaemia, and during pregnancy or breastfeeding.
What happens when you stop?
This is where the two differ most, and where many people’s experience of the injections catches them out.
Weight regain after stopping is common, and the evidence is strong. A 2026 analysis of 37 trials and 9,300 people, published in the BMJ, found people regained around 0.8 kg a month after stopping, about four times faster than after diet programmes, with most back at their starting weight in about 18 months. In SURMOUNT-4, people who stayed on Mounjaro kept losing weight, while those switched to placebo regained a substantial amount. An extension of STEP 1 found people regained two-thirds of their lost weight within a year of stopping Wegovy, and their blood pressure and blood sugar improvements faded too.
This is not a failure of willpower. The medicine’s effect on appetite fades within days of stopping, and doctors increasingly treat obesity as a long-term condition, much like high blood pressure, where results last while treatment continues.
It is also not everyone’s story. Cambridge researchers found regain tends to level off, with people keeping off around a quarter of what they lost. A Cleveland Clinic analysis of nearly 8,000 patients found that many avoided major regain by restarting, switching medicine or making lasting lifestyle changes.
With fat freezing, the fat cells destroyed in the treated area do not grow back, and you do not need to keep paying to hold the result. That is its real advantage, but it comes with a catch: the remaining fat cells can still grow, and it does nothing to stop you gaining weight elsewhere. It lasts best if your weight stays stable.
Why people choose fat freezing
- The medicines are not meant for them. The injections are generally prescribed for a BMI of 30 or more, or from 27 with a weight-related condition. Many people with stubborn fat are well below that.
- They have one specific area in mind. Injections cannot choose where the weight comes from. Fat freezing can.
- They do not want an open-ended commitment. A short course, with no weekly injections or monthly bills, appeals to many.
- They want to avoid the side effects of medication, particularly nausea and other stomach problems.
When the injections are the better choice
If your BMI is over 30, if you have a lot of weight to lose, or if you have a weight-related condition such as type 2 diabetes, high blood pressure or sleep apnoea, fat freezing is not the answer. It is not designed for this, and its US clearance for most body areas is for people with a BMI of 30 or under. Please talk to your GP or a registered prescriber, because the medicines may do you real good. And if you are already taking one, speak to your prescriber before changing anything.
Can you do both?
Yes, and many people do, one after the other. Medication can bring overall weight down, and fat freezing can then treat stubborn areas that remain. It is best to wait until your weight is stable, ideally for 3 to 6 months, because results are harder to judge while you are still losing. Fat freezing does not tighten skin and can make looseness more noticeable, so be honest with yourself and your practitioner about what is bothering you.
So which is right for you?
Ask what you are really trying to change. If it is your weight or your health, start with a doctor. If you are close to a weight you are happy with and one area will not shift, fat freezing may be worth considering, as long as you are comfortable with the risks and realistic about a gradual, modest change.
If that sounds like you, you can read more about fat freezing or book a free consultation. We will look at the area with you, and if it is not the right treatment for you, we will say so.