The skinny Undergo liposuction, and your friends may see less of you. But research published last week in the New England Journal of Medicine suggests the procedure won't make you healthier inside. Researchers following 15 obese women, including seven with diabetes, found that the surgical removal of body fat in each produced little change in several measures of heart disease and metabolic risk, including blood pressure, cholesterol level and insulin sensitivity. Levels of C-reactive protein, an indicator of heart-endangering inflammation in the blood vessels, were also unchanged.

The rub The findings were unexpected. "We removed literally 22 pounds of fat from most women -- I was disappointed and surprised that there wasn't a metabolic effect," said Samuel Klein, director of the Center for Human Nutrition at the Washington University School of Medicine in St. Louis, who ran the study. For metabolism and heart health to improve, Klein concluded, you have to go the old-fashioned weight-loss route -- burning more calories than you take in.

The knife Liposuction is the most popular aesthetic surgery in the United States; almost 400,000 Americans -- most of them women -- undergo it each year, according to the American Society for Aesthetic Plastic Surgery. While the surgery entails risks such as infection and blood clots, it also offers health benefits, including an increased ability to exercise and less stress on joints.

New York plastic surgeon Sharon Giese was unpersuaded by the study. She noted that, unlike Klein's subjects, most liposuction patients are not medically obese -- they don't score over 30 on the body mass index (BMI), a widely used measure of weight relative to height. Giese said her research shows that, for non-obese women, insulin levels and blood pressure readings improve after liposuction.

-- Brian Reid