Obesity has been associated with increased risk of a number of types of cancer. The risk of cancers of the colon and rectum, breast, body of the uterus (endometrium), kidney and esophagus have all been associated with obesity. Other cancers whose risk is likely to be related to obesity are cancers of the pancreas, liver, gall bladder and the cardia (uppermost region) of the stomach. The level of risk for most of these cancers is moderate, having relative risk values between 1.5 and 2.9. The contribution of obesity to the occurrence of cancer is considerable. In high income countries, such as the United States, obesity is considered to be the third largest contributor to cancer incidence behind smoking and alcohol use.