As many as 100,000 cases of cancer could be prevented in the U.S. each year if Americans get rid of their excess body fat. The estimates suggest that heart disease, diabetes, and joint problems aren’t the only illnesses in which rampant obesity is causing havoc.
A 2007 report from the American Institute for Cancer Research and the World Cancer Research Foundation reviewed hundreds of studies and found what researchers called “convincing evidence” that obesity was tied to several cancers. Those included cancer of the esophagus, pancreas, and kidneys. It also included colorectal cancer and endometrial cancer (a form of uterine cancer).
The researchers estimate that excess body fat is the cause of 33,000 breast cancer cases each year, nearly one-sixth the total cases in postmenopausal women. Obesity could be to blame for nearly 21,000 cases of endometrial cancer and more than 13,000 cases of colorectal cancer per year.
Fat cells produce estrogen, which are now known to be a factor in breast cancer and endometrial cancer. Fatty tissue also affects the way the body metabolizes insulin, which can alter how sugar is processed and how it ultimately gets to cells.
The estimates suggest maintaining a normal weight could prevent half of all endometrial cancers, a third of all esophageal cancers, and a quarter of all kidney cancers.