Weight loss surgery can sometimes reverse type 2 diabetes and ease other obesity-related conditions. Now, new research suggests that obese women who undergo bariatric surgery experience a 42 percent drop in their cancer risk.
Exactly why this occurs and whether it’s also true for obese men is not yet clear. Obesity is a known risk factor for colon, breast, endometrial, kidney and esophageal cancers. However, the researchers found that the surgery-related weight loss and drop in caloric intake did not seem to be solely responsible for the decline in the women’s cancer risk, according to the report in the July issue of Lancet Oncology.
“Evidently, one or several risk factors for cancer are favorably influenced by bariatric surgery in women,” said lead study author Dr. Lars Sjöström, a professor of medicine at Sahlgrenska University Hospital, in Gothenburg, Sweden.
In the study, researchers followed two groups for an average of 10.9 years — 2,010 men and women who had weight loss surgery and 2,037 obese people who did not undergo surgery. Those who had the surgery lost roughly 44 pounds, compared to just 3 pounds in those who did not. During the 10-year period, 117 people who underwent surgery developed cancer, as did 169 of their counterparts who tried to lose weight non-surgically.
There were 79 cancers diagnosed in women who had surgery, compared with 130 cancers in the other women; a wide variety of cancer types were lower in women who had bariatric surgery. Still, the researchers did not find a statistical link specifically between weight loss or caloric intake after surgery and the reduction in cancer risk. They also found no cancer risk reduction for men who had surgery.