Fat removed by liposuction returns after a year, study finds

It is the quickest way to slender thighs and a pert behind, and has been practised for more than 30 years. But no one knew if liposuction – the physical removal of fat from the abdomen, bottom, hips, or elsewhere – worked in the long term.

Now researchers have conducted the first randomised trial, and come up with an unexpected result. The fat removed all returns – but in a different place.

Liposuction is a simple but crude mechanical process involving the insertion of a tube under the skin attached to a powerful vacuum pump which sucks up the fat like a Hoover sucking up dust.

Thighs and abdomen – the most popular areas – shrink overnight, delivering a result, after the bruising has healed, that would take months of dieting to achieve. Best of all, the treatment is targeted, so fat is lost only from the chosen areas.

More than 3,300 liposuction procedures were carried out by members of the British Association of Aesthetic Plastic Surgeons last year, and hundreds more will have been performed by other surgeons. The cost is from £3,000 to £5,000.

But the trial carried out by researchers from the University of Colorado found that a year after the procedure, the fat suctioned out had all returned and been "redistributed upstairs" – around the shoulders, arms and upper abdomen.

Rudolph Leibel, an obesity researcher at the University of Columbia, told The New York Times that the body controls the number of fat cells as carefully as it controls the amount of fat. When a fat cell dies, it grows a new one to replace it.

Liposuction, however, surgically destroys the fishnet structure under the skin, which may be why the fat cells don't regrow in the place from which they were removed. Instead the body compensates for their loss by growing new fat cells in other areas.

"It's another chapter in the 'You can't fool Mother Nature' story," Dr Leibel said.

The study, published in Obesity, involved 32 women aged in their mid-thirties and of average weight. Just under half (14) had a modest amount of fat removed by liposuction from their hips and thighs, while the remainder (18) acted as controls. They were promised they could have the procedure at a reduced cost, if they still wanted it when they had the results.

Identical measurements of all the women were carried out at six weeks, six months and a year, which revealed how the body "defends" its fat. After six weeks the treated patients had lost 2.1 per cent of their fat, compared to 0.28 per cent in the control group, but this difference had disappeared at one year. Though the women's thighs remained thinner after a year, the missing fat had found its way back to their stomachs.

Despite the questionable results, the women in the study were happy with their treatment, the researchers reported. They had hated their hips and thighs and had successfully got rid of that fat. Those in the control group were also not discouraged - more than half still chose to have liposuction even after learning of the results.

But there are risks. Denise Hendry, wife of the former premiership footballer Colin Hendry, won a six-figure compensation payment in 2006 over a botched liposuction operation. She suffered a punctured bowel during the procedure in 2002, which led to blood poisoning. She died of meningitis in July 2009.