In the world of nutrition, it's hard to talk about sugar without talking about insulin. That's because insulin is sugar's little chaperone to the cells, and when too much of it is consumed and our insulin can no longer handle it properly or at all, the body revolts.
One connection that has been well documented in the literature is the link between insulin resistance and cancer. A 2013 study found that sugars in the intestine triggered the formation of a hormone called GIP, controlled by a protein called β-catenin that is completely dependent on sugar levels.
That in turn increases the amount of insulin released by the pancreas. Researchers found that β-catenin may in fact affect the cells' susceptibility to cancer formation. Further studies have found negative associations between high sugar and starch intake and survival rates in both breast cancer patients and colon cancer patients.