A new U.S. study suggests that weight-loss surgery may help some severely obese people reduce their risk of cancer by at least 33 percent, especially for several types of obesity-related cancers, including breast, endometrial, pancreatic and colon cancers. According to the report, the researchers examined the health insurance and health care systems in the western region of the U.S. and collected medical data from several states, including data on nearly 22,200 people who underwent weight-loss surgery between 2005 and 2012 as well as more than 66,400 obese people who did not undergo weight-loss surgery, with more than 80 percent of the study participants being women. The findings showed that within 3.5 years of the surgery, about 2,500 people developed cancer. However, compared to those obese people who did not have surgery, those who had weight loss surgery were 1/3 less likely to develop cancer, especially the types of cancer associated with obesity. The authors of the study also noted that the rate of all diagnosed obesity-related cancers in the United States is as high as 40 percent. The researchers noted that weight-loss surgery reduces the risk of cancer, especially for several types of obesity-related cancers, including breast, endometrial, pancreatic and colon cancers. The study did not prove a causal relationship between weight-loss surgery and avoiding certain cancers, but the risk reduction was significant. According to the report, weight-loss surgery reduces the risk of breast cancer in postmenopausal women by 42 percent and the risk of endometrial cancer in obese women by 50 percent. Shore noted that the risk of postmenopausal breast and endometrial cancers is closely linked to estrogen levels, which can be effectively reduced by weight-loss surgery. In addition, the study also found that weight loss surgery also reduced colon cancer risk by 41 percent and pancreatic cancer risk by 54 percent. The researchers also said that this surgery helps prevent diabetes and lower insulin levels, which may reduce the incidence of pancreatic cancer. A portion of patients considering weight loss surgery may be doing so to reduce their cancer risk, but in addition to this, there are many other factors that go into having the surgery, such as avoiding diabetes, high blood pressure, and improving quality of life. In conclusion, this study also provides another positive reason to undergo weight loss surgery.