Liposuction results for women who underwent liposuction of the lower belly and thighs gained all the weight back in the upper abdomen and elsewhere, a team of University of Colorado researchers has reported.
The liposuction results study, published in the April edition of the journal Obesity, generated some immediate buzz. UCH physician and University of Colorado School of Medicine Professor Robert Eckel, MD, who launched and guided the study, was on National Public Radio’s “Science Friday” talking about it last week. The New York Times “Week in Review” ran a piece the previous Sunday. WebMD joined the fray, as did, for those who prefer to read in Portuguese, the Brazilian science magazine Superinteressante. The list is sure to grow.
It’s big news for patients and providers, too. Liposuction is the second-most popular form of plastic surgery, after breast augmentation, in the United States, where more than 200,000 procedures are performed each year. And the results of the study seemed counterintuitive. One might think that if a procedure literally excises fat, the body would simply go about its business without the extra baggage.
But the first-ever randomized, controlled trial to look at liposuction results found that isn’t so. The fat simply resettled in other parts of the body.
The results don’t call into question the effectiveness of sculpting via liposuction, both Eckel and plastic surgeon Christopher Law, MD – who performed the liposuction procedures on study subjects – emphasized. The fat largely reorganized elsewhere, preserving the results of the procedure. Half the patients in the control group opted for liposuction after the randomized study closed, in fact.
However, Eckel said, one question the study begs is whether the surgically triggered rearrangement of fat – from thighs to the belly, for example, where fat has been shown to increase the risk of diabetes, heart disease and cancer – might have long-term health consequences.
More papers based on the team’s research are on the way, though they won’t address that question. One will look at patterns of gene expression in fat in the upper abdomen, flanks and hips, to see if fat in the upper abdomen indeed harbors seeds of later trouble. Another seeks to assess whether the genes in liposuctioned fat tissue hold clues as to where new fat will reappear, Eckel said.
It took several years, $1.6 million in National Institutes of Health (NIH) funding, the collaboration and coordination of multiple CU School of Medicine specialists, and the capabilities of UCH’s Clinical and Translational Research Center (CTRC) to produce the study’s surprising results.
Teri Hernandez, PhD, RN, took the lead in laying the groundwork for the research. In 2002, when the NIH grant came in, she began the work of contacting and qualifying research subjects. Later, she measured arms, thighs, waists and skin folds and analyzed the study’s many data points.
The study needed women (or men, though there was much less interest among them) who were of roughly normal weight and who had not dieted heavily in the past, among other factors. Participants agreed to submit to a series of tests to measure body fat, done after three days of meals from the CTRC’s Metabolic Research Kitchen in the Leprino Building. They also submitted to blood tests as well as fat biopsies, and stayed overnight at the hospital.
Then, about half of them – the selection was random – got liposuction at a reduced price. The others had the option of receiving liposuction, also at the much-reduced cost, at the end of the study.
The average age of the subjects was 36. In general, Eckel said, “This was your perfect cosmetic-surgery candidate. She doesn’t like her saddle bags or lower abdomen.”
Fourteen women received liposuction, which removed an average of six pounds of fat. Eighteen others were in the control group. Researchers took fat, blood and body-fat measurements from both groups at the start of the study, at six weeks, six months, and a year afterward. Eckel and Hernandez had hoped to follow participants for three years, but delays early in the study shortened it. It turned out that a year was enough.
The results confirmed what plastic surgeons and frustrated dieters had long suspected: the human body has, as Law described it, a “Fat-O-Stat.” Give a person a certain amount of food and exercise, and his or her overall body fat will settle at a certain amount. In Eckel’s words, the body “defends” its fat. How and where the brain’s fat defense is organized, Eckel said, remains a mystery.
The liposuction results study managed to demonstrate fat defense with a scientific rigor that outside experts have made a point of praising. That rigor was the product of an enormous amount of planning and effort. To assess body fat, as well as the fat’s physical distribution, researchers measured bone mineral density, abdominal and limb circumferences and skin folds, and took magnetic resonance images.
The team also assessed resting metabolic rates, insulin sensitivity, and a host of substances in the blood (various stripes of cholesterol, glucose, free fatty acids, and glycerol, among them). In addition to Hernandez and Eckel in the Division of Endocrinology, Metabolism and Diabetes, the study’s nine co-authors included Elizabeth Stamm, MD, and Ann Scherzinger, PhD, of CU’s Department of Radiology; as well as CU School of Public Health statistician John Kittelson, who faced a deluge of numbers.
Law performed all 14 liposuction surgeries; fellow plastic surgeon Lawrence Ketch, MD, served on the study’s science advisory and review board. Eckel said the willingness of both to work on a study that had the potential of questioning the outcomes of such a popular – and lucrative – plastic surgery procedure was commendable.
Though Law did wonder if he might look like a traitor to his colleagues, he said he never had reservations.
“We’re the University of Colorado,” he said. “We want to find out the real truth about things.”
That truth, he said, includes detailed evidence of how hard it is to control body fat by dieting or otherwise. “I think smart people will look at this and recognize that, armed with real information, you’ll end up with happier patients,” Law said.