Weight-loss surgery is more effective than diet and exercise as a treatment for obesity, according to a review of health studies involving almost 800 people.
Surgery such as gastric banding, gastric bypass or sleeve gastrectomy led to on average 26 kilograms (57 pounds) more weight loss after two years than non-surgical treatment, which included diet, exercise, behavioral therapy and medicines, according to an analysis of 11 studies of 796 obese people. The research was published today in the British Medical Journal.
While the results are limited to two years’ follow-up after surgery, the analysis provides further evidence supporting medical procedures to address the obesity epidemic. At least 2.8 million people die each year from being overweight or obese, which raises risks of diabetes, heart attacks and strokes.
“This meta-analysis provides comprehensive evidence that, compared with non-surgical treatment of obesity, bariatric surgery leads to greater body weight loss,” according to the authors, led by Viktoria Gloy at the University Hospital Basel in Switzerland. “The evidence beyond two years of follow-up, in particular on adverse events, cardiovascular diseases and mortality remains unclear.”
Surgery also led to higher remission rates of type 2 diabetes, according to the review. The most common side effects were iron deficiency anemia and the need to re-operate. Another complication may be frequent diarrhea.
While diet and exercise are more cost-effective options, studies show that for most people they are not sustainable for weight-loss. As many as two-thirds of those on diets regain more weight than they lost within four or five years, according to an analysis of 31 long-term studies on dieting by researchers at the University of California at Los Angeles.
Obesity is “one of the greatest public health problems in industrialized countries,” according to the authors of the study published today. In the U.S., 67 percent of the population is overweight or obese, while the figure is 40 percent to 50 percent in most European countries, they said.
According to current guidelines, bariatric surgery can be considered for people with a body mass index of at least 40 or a BMI of 35 for those with an obesity-related disease.
Body mass index is a measure of body fat calculated using a person’s height and weight. People with a reading of 30 or more are considered obese, according to the U.S. Centers for Disease Control and Prevention.