For every cancer, there are certain groups of people who are more at risk than everyone else. Depending on the cancer, increased risk factors include smoking tobacco, ethnicity or age. Those risk factors, however, are fairly well known. For instance, it's no secret that smoking tobacco increases one's risk of developing lung cancer. What many people don't know is that obesity may be one of the biggest risk factors for the development of cancer.

According to a recent study by the American Institute for Cancer Research, obesity can raise one's risk for an array of cancers. These include colon, breast, endometrial, kidney, esophageal, liver, gallbladder, ovarian and pancreatic cancer. More than 150 million people in the United States can be classified as being obese, and approximately two-thirds of the United States population is overweight.