Obesity is a punching bag, and it takes the blame for a lot of health problems. Now the American Institute for Cancer Research is pointing its fingers at obesity for causing some cancers. According to a recent study, more than 100,000 cancers are caused by excess body fat. And more than that, extra fat can also make cancers harder to treat and give victims a more difficult struggle against the disease. Knowing that you may be preventing a future cancer makes hitting the treadmill and watching those portions just a tiny bit easier, doesn’t it?