Health experts have long warned that sugar-laden high-fat diets raise a person’s likelihood of developing colon cancer. Now researchers say they know how and why, and that could lead to improvements in diagnosing the disease.
A new study led by Temple University’s Fels Institute for Cancer Research and Molecular Biology found genetic differences in people who develop colon cancer that may allow tumor cells to feed on insulin.
Researchers said the study, published in the American Association for Cancer Research’s journal Cancer Prevention Research, could help lead to new ways to determine the likelihood a person is prone to developing colon cancer through a saliva or blood test, in addition to a colonoscopy.

“There have always been questions about why things like diet and obesity are independent risk factors for colon cancer,” said lead researcher Carmen Sapienza. “This study suggests how and why high fat diets are linked to colon cancer.”
For the study, researchers compared colon tissues from cancer patients to those of healthy people. In the cancer patients, they found genetic processes involved in breaking down carbohydrates, lipids and amino acids — abundant in fatty diets — appear to have been retrained in ways that differed from people without cancer.
Cancer patients process insulin and blood sugar “at completely different levels than people who don’t have colon cancer,” Sapienza explained, adding that cancer cells “love insulin and studies have shown that tumors feed off of insulin.
“[But] Insulin is only supposed to be expressed in your pancreas, so having this extra insulin is bad.”
The study was partly funded by the National Institutes of Health.