The role of insulin which is a hormone secreted in response to the ingestion of carbohydrates in the body is to shuttle glucose (from the breakdown of those carbohydrates) out of the blood and into cells where it is needed to produce energy from the calories we ingest. The more carbohydrates you eat, the more insulin the body releases to process it.
In insulin resistance, some cells become desensitized to the action of insulin. This inaction only serves to stimulate the pancreas to secrete ever-larger amounts of the hormone in an all-out-effort to get glucose into cells. The excessive response leads to too much insulin in the blood, a condition called hyperinsulinemia. Weight gain aggravates insulin resistance, which in turn raises hormone levels known to feed the growth and development of cancer cells.
In addition to regulating blood glucose, insulin has other functions, one of which is to act as a growth hormone for cells; when nutrients are plentiful after a meal, insulin helps cells use the nutrients to grow. Insulin also stimulates the release of other more potent growth hormones, like insulin-like growth factor-1 (1GF-1), and may make cells more receptive to this and other growth factors. Unfortunately, mounting evidence suggests that cancer cells feed off these growth hormones just as healthy cells do. An excess of insulin can cause them to grow uncontrollably and to resist the programmed cell death that is nature’s way of halting the cancer process.
Diabetes and colon cancer share many of the same risk factors, including being overweight, being physically inactive and eating a diet high in calories, saturated fat and sugar, and low in dietary fibre. A number of studies have analyzed the potential link between insulin resistance and colon cancer, and most tend to show an association between colon cancer and high levels of both circulating insulin and C-peptide a marker for hyperinsulinemia and inflammation. Elevated insulin and growth hormone levels are likely driven not just by excess weight, but also by a sedentary lifestyle and the diet high in refined sugars and unhealthy fats, while low in nutrient-rich, high-fiber foods. Recent research suggests insulin resistance may also play a role. Beyond estrogen, these findings may further explain the connection between obesity and the development of breast cancer, as well as its recurrence.
One can opt for tests to determine if, and to what degree, you are insulin resistant like FPG or GTT. The good news is that even small changes in weight and physical activity can improve insulin resistance and lessen its negative health effects. Do the following now:
1. Lose weight if you are overweight.
2. Establish a regular exercise routine. Physical activity is known to be a major modifier of insulin resistance. Simply walking 45 minutes four to five times per week will improve insulin resistance and overall health.
3. Eat a healthful diet of whole foods. Insulin resistance may be fueled by diets high in sugar, saturated and Tran’s fats, so it’s key to eat more fruits, vegetables, whole grains and fish, and less animal fat and processed carbohydrates. The monounsaturated fats in olive and canola oils, nuts, seeds and avocados also improve insulin sensitivity, so include them regularly.