Risk factors for colorectal cancer rising; experts call for better diet, health

A new review article discussed how early onset colorectal cancer – defined as being diagnosed at age 50 and younger – continues to steadily rise in the United States, and that public health measures need to address the increased risk factors.

The article was written by Frank Sinicrope, MD, an oncologist and gastroenterologist at Mayo Clinic Cancer Center in Minnesota and was published in The New England Journal of Medicine.

While the research emphasized an increase in early onset colorectal cancer diagnosis, it also pointed to a decline in later-onset cases due primarily to a shift in screening age. In the early 2000s, screenings took place at the median age of 72 years old, compared to now, where screenings have shifted the median age at diagnosis to 66 years old.

Sinicrope said the Mayo Clinic, as well as other clinics around the country, are seeing a significant increase in the number of younger patients diagnosed with colorectal cancer. He said most cases are without a known hereditary basis and have no identifiable cause.

"Public health measures are needed to address risk factors for colorectal cancer, beginning in adolescence, including poor dietary habits and physical inactivity,” Sinicrope said in a statement.

According to Sinicrope, diets with high intake of red and processed meat, as well as refined grains and processed sugar can alter gut microbial composition, resulting in chronic inflammation, increased obesity, and a higher risk of colorectal cancer.

"Evidence suggests that a plant-based diet and more physical activity may help to promote a more a favorable gut microbiome, which in turn may reduce the risk of colorectal cancer," he said.