Summarized by Robert W. Griffith, MD
July 16, 2004
Introduction
Obesity is associated with many of the risk factors for diabetes and coronary heart disease. And losing weight can improve the results of tests for these risk factors (blood sugar, blood pressure, and so on). So one might expect that removing body fat by liposuction would also help in this regard. A study reported in the New England Journal of Medicine has examined this possibility. The purpose of the study was to measure the effects of liposuction on the metabolic risk factors for coronary heart disease in obese women. Here's a summary of the findings.
What was done
Fifteen women with abdominal obesity (waist size more than 39 inches, or 100 cm) were enrolled in the study. Their average body mass index (BMI) was 37.7. Eight of them had normal glucose tolerance (i.e. they weren't diabetic) and 7 of them had type 2 diabetes, treated with oral medication.
Before their surgery, each woman had a test to show the effectiveness of insulin on the blood glucose levels in their liver, muscle, and fatty tissues after intravenous glucose administration followed by an infusion of insulin; this was a measure of insulin sensitivity, which is reduced in type 2 diabetes.
Other tests measured markers of chronic inflammation in the blood (C-reactive protein or CRP, interleukin-6, and tumor necrosis factor), blood lipids, and blood pressure.
A week later, the women had 'large-volume' liposuction (removal of more than 4 liters of liquid, which is 60% fat); in fact, on average, 16-17 liters were removed. Ten to 12 weeks later the tests done before operation were repeated.
What was found
The non-diabetics had their body fat reduced by 18%, and the diabetic by 19%, 10 weeks after liposuction. Average BMI levels was reduced by 2.3 points in non-diabetics and by 3.9 points in diabetics.
What was notable was that liposuction had no significant effect on insulin sensitivity of the liver, muscle, or fat tissue; it did not alter the inflammatory blood markers predictive of coronary artery disease; and other cardiac risk factors - blood pressure, blood glucose, blood lipids - were also unaffected.
What this means
Clearly, abdominal liposuction had no significant beneficial effects on the abnormalities often classified as the metabolic syndrome, and which are associated with an increased risk of diabetes and coronary heart disease. Why was this so? An accompanying editorial in the same medical journal tries to give an explanation.1
Dr Kelley points out that losing weight by dieting and exercise does improve metabolic and cardiovascular risk factors. So what's the difference when losing weight by liposuction? It seems that these effects are produced by the 'negative energy balance' induced by eating fewer calories and burning more calories in exercise. Liposuction doesn't produce a negative balance in this sense.
Before we dismiss liposuction as a form of treatment for obesity, we should remember that it can help considerably with people's appearance, and reducing weight quickly this way can decrease the risk of heart failure and improve knee osteoarthritis. Nevertheless, liposuction is not the panacea that it appeared it was going to be at one time. Better to go with a suitable calorie-restricting diet and plenty of exercise.
Source
Absence of an effect of liposuction on insulin action and risk factors for coronary heart disease. S. Klein, L. Fontana, V. Leroy Young, et al., N Engl J Med, 2004, vol. 350, pp. 2549--2557