Does it hurt? How does it work? Our experts answer your fat freezing FAQs.
Medically reviewed by Dr Roger Henderson and words by Annie Hayes
Fat freezing, also known as ‘CoolSculpting’, is a form of non-surgical liposuction used to reduce pockets of excess body fat.
It works by freezing and killing fat cells in the part of your body that you’re having treated. Over time, the cells are naturally broken down by your body and flushed out through your liver.
Dr Galyna Selezneva, aesthetic doctor at the Rita Rakus Clinic, and Dr Hennah Bashir, advanced aesthetic physician and founder of Dr Henna Aesthetics, talk through the fat freezing procedure, including where the treatment works best, what to expect from a session, and how it takes to see results:
How does fat freezing work?
Also called cryolipolysis – or cryogenic lipolysis – fat freezing was first discovered by doctors at Harvard, who noticed that children who ate a lot of ice lollies developed fat loss and dimples in their cheeks, says Dr Bashir.
‘Cryolipolysis was developed off the back of the discovery that fat cells are highly sensitive to cold and can actually be destroyed by very low temperatures,’ she says. ‘The procedure involves applying antifreeze membranes and supercooled plates to areas of superficial fat.’
‘Fat cells are highly sensitive to cold and can be destroyed by very low temperatures.’
Exposing freezing temperatures (anywhere between -11 to +5 °C) to subcutaneous fat – the kind that sits directly beneath the skin – damages fat-storing cells, triggering the body to eliminate them. ‘As the fat cells that are frozen are permanently eliminated from the body, results are often much longer-lasting than other fat-removing treatments,’ says Dr Bashir.
Does fat freezing work?
Studies have confirmed that a single CoolSculpting treatment can reduce a fat deposit by up to 25 per cent, says Dr Bashir. But there’s a caveat. ‘Fat freezing cannot completely eliminate all fat from a body area,’ she says. ‘It’s important that patients using this treatment take care of their diet, drink plenty of water and take regular exercise, or it’s likely that the removal of fat by the treatment will be masked by new fat deposition in treated areas.’
Which body parts does fat freezing work on?
Fat freezing isn’t effective on every type of fatty tissue. ‘Deep fat can be stored under the muscles around organs and this fat cannot be reached by cryolipolysis,’ says Dr Bashir. ‘Fat freezing works best on very superficial stubborn fat – such as cellulite – which lies just under the skin.’
CoolSculpting applicators are designed to pinch fat between freezing plates, so if the fat cannot be ‘pinched’, it’s unlikely that the applicators will be able to effectively treat these areas, Dr Bashir continues.
So, where does fat freezing work best? Typically, the area beneath the chin, on the underside of arms, inner and outer thighs, abdomen, hips and lower bottom give good results.
‘All these areas commonly have very superficial mobile fat deposits that can be pinched and pulled into an applicator for treatment,’ says Dr Bashir. ‘If an area has a lot of fat under the skin, but it isn’t mobile fat and cannot be pinched – for example, over the lower leg or back – fat freezing is basically useless.’
How long does fat freezing take?
It doesn’t take long to kill fat cells. Fat is more temperature-sensitive than your skin or other organs, says Dr Selezneva. Between 35 minutes and one hour and 15 minutes is enough time to cause the cells to crystallise and die, though the treatment time will vary depending on the area.
Fat from the targeted area is sucked into a vacuum cup lined with supercooled plates and held in place for the allotted time. ‘Most people find it comfortable enough to snooze or watch Netflix while being treated,’ says Dr Bashir. ‘Most fat freezing treatments last an hour and have no downtime or side effects after the session ends.’
It often takes a few treatments to get optimum results with CoolSculpting, depending not only on how dense the fat deposits are, but also your lifestyle outside of treatment. ‘Fat freezing works best for those with stubborn pockets of fat who otherwise have healthy diets and exercise regularly,’ says Dr Selezneva.
Does fat freezing hurt?
The patch of skin that is being treated can initially feel sore before turning numb, but the procedure is not painful in itself. As Dr Selezneva points out, pain is subjective, and we all will experience it differently. Generally, fat freezing is reported to be mildly uncomfortable as opposed to painful.
‘There can be some discomfort from the tugging feeling produced by the vacuum in the applicator cup,’ says Dr Bashir. ‘The area may ache for up to a week after treatment – as if affected by a muscle sprain caused by a heavy workout – and some red discolouration of skin may last a few hours after the cup is removed.’
What are the results of fat freezing?
It can take up to 12 weeks to see results from fat freezing, but this varies from person to person. ‘Some of my enthusiastic patients start seeing results after one week,’ says Dr Selezneva, ‘but I always say it takes four weeks to start seeing the results, and 12 weeks for the full results.’
The more treatments you have, the more results you’ll see, since fat cells are destroyed during every treatment. ‘After your first couple of treatments you can end up with a very visible change whereby you drop up to two dress or trouser sizes – but it’s important to remember fat reduction by cryolipolysis is a marathon, not a sprint,’ says Dr Bashir.
How many sessions do you need?
It really depends on the results you’re looking for. ‘Some patients will have sufficient visual reduction after only one treatment, and some will need to repeat again,’ says Dr Galyna Selezneva. ‘This depends mostly on the volume and density of the initial fat layer.’
On average, five cycles of treatment spaced four to eight weeks apart is enough to bring measurable results.
On average, five cycles of treatment spaced four to eight weeks apart is enough to bring measurable results, says Dr Bashir. ‘It’s important to allow the body time to eliminate the dead fat cells and for any soreness at the treated site to resolve, so leaving four weeks – but ideally eight weeks – between each treatment is normal.’
Is fat freezing safe?
It’s rare – but not impossible – for serious side effects to occur with CoolSculpting. ‘If the incorrect amount of antifreeze is used or the machine settings are wrong, there’s a potential for the cooling plates to produce cold burns and scarring,’ says Dr Bashir.
For this reason, it’s important to only undertake this treatment with a reputable and experienced provider. ‘Overall, fat freezing is safer than alternatives like liposuction or fat-dissolving injections,’ she says. ‘It’s non-invasive, and harnesses a natural process whereby the body eliminates fat cells exposed to severe cold.’