Colorectal cancer is one of the most widespread globally, after breast, lung, and prostate cancer. But mortality is substantially decreased, thanks to progress in research, early detection, and improved therapies.

Colorectal cancer is the only one, among the 156 types of cancer known today, suspected of slightly increasing its incidence (by 1% in absolute terms) for the excessive consumption of red and processed meat. Major risk factors include hereditary genetic factors, smoking, obesity, sedentary life, and an unbalanced diet. Generally, red meats and cured meats are referred to as foods to be restricted to keep away the risk of this disease. Is it meat’s fault?

People with irritable bowel syndrome, chronic inflammatory bowel diseases, such as ulcerative colitis and Crohn’s disease, benign intestinal polyps, or with relatives already with a history of colorectal cancer have a higher predisposition and risk of developing cancer. Prevention is essential, such as having regular check-ups but also following a healthy and active lifestyle. A wrong diet alone is not the cause of colon cancer, but it can contribute to its occurrence and other risk factors.

Following the IARC-WHO report in 2015, red and cured meats have become the targets of meat detractors. Even today, they mention that report in bad faith despite the denials of the IARC itself. Moreover, after six years, research has made significant progress with more accurate studies showing the firm limits of the past studies which calculated the risk of colon-rectal cancer. However, the risk was less than 1% in absolute terms, much lower than other risk factors, such as smoking, alcohol, pollution, and the presence of abdominal fat, even though it was also calculated on very high quantities of meat.

For example, in studies in rats, quantities of heme iron corresponding to the amount of iron in 4 kg of red meat have been inoculated. A dose not only excessive and not responding to the regular consumption of a person, but also wrong for a simple reason: taking only one component of meat, in this case, iron and inoculating it individually as an active ingredient, is a serious methodological error, that does not give a vision of what happens in a natural and varied diet.

Food is a complex matrix of substances that interact with each other and are suitable for us. On the contrary, if we took these substances individually and injected them in large quantities as active substances, all the best nutrients would become harmful.

All new studies of best scientific quality that reviewed the past studies considered in the IARC-WHO report have not confirmed any link between red meat, cured meats, and colorectal cancer. Even a significant correlation with other diseases, such as cardiovascular diseases, has not been confirmed. On the contrary, current studies show only the health benefits of meat, even with higher amounts of red meat than recommended.

There are studies that show a greater risk of colorectal cancer in vegetarians and vegans instead. They abuse fibers and vegetables containing potentially toxic anti-nutritional factors such as saponins and lectins. Too many fibers damage the intestine, and the frequent ingestion of saponins and lectins can increase intestinal permeability. This causes malabsorption, nutritional deficiencies, and the “leaky gut“, with “holes” in the intestinal walls. But also food intolerance, celiac disease, and, in the most severe cases, autoimmune diseases. For this reason, those who suffer from these diseases or irritable colon and ulcerative colitis cannot eat legumes, whole grains, dried fruits, and too fibrous raw vegetables.

Red meat should not be demonized, even for patients with cancer. It provides essential nutrients that help the recovery in the post-operative phase, avoiding malnutrition, the depletion of energy, protein, and nutrient reserves in the body at this delicate stage.

In a healthy diet, it is recommended to consume 500 grams of red meat per week (500 grams of cooked weight, equivalent to about 700-750 grams of raw weight depending on the cut and the cooking method). Meat must be cooked properly, not burnt, at low temperatures, and well preserved. These indications apply to everyone, including patients with cancer.