Madrid, 30 March 2023-. The incidence of colon cancer in Spain continues to rise. According to data from the Spanish Society of Medical Oncology (SEOM), it is currently the most frequent type of cancer, with more than 42,000 new cases diagnosed each year1. Faced with this situation, it is essential to raise awareness of how diet and nutritional habits influence the prevention of this type of cancer. As Pedro Robledo, head of the Clinical Nutrition and Dietetics Unit at MD Anderson Cancer Center Madrid explains, "there are indications that a diet with high levels of folates and polyunsaturated fatty acids can contribute to a reduction in the incidence of colon cancer, as well as adequate consumption of foods rich in fibre. This can be achieved with a regular daily intake of fruits, vegetables, whole grains and legumes".
In general, he adds, "there is significant scientific evidence that a varied diet and appropriate calorific intake is a primary tool in the prevention of numerous diseases. When a diet is too selective, lacking variety or based only on one type of food, it is unlikely to provide benefits for general health care."
On the other hand, factors including excessive caloric intake, with a greater percentage of animal fat and a high consumption of processed products and red meat, contribute to the proliferation of chronic diseases, such as obesity, which are related to bowel cancer. It is estimated that these unhealthy eating habits, together with a sedentary lifestyle, may be the cause of a higher incidence of colon cancer in young adults between 25 and 30 years of age and, in general, in the population under 50 years of age2.
With this in mind, the current challenge facing nutrition experts involved in cancer management is to provide patients with dietary recommendations based on evidence-based data. In this regard, new studies have recently been published on the subject of intestinal permeability and how the microbiota, which is affected by the food we consume, may have a positive impact on the development of colon cancer. These hypotheses now look to become a central element of ongoing research into this type of tumour.
Studies on the role of microbiota in tumour development
According to the MD Anderson Madrid expert, "the study of the microbiota, in all its broad spectrum, has enabled us to conclude that certain bacteria and viruses may have a beneficial effect in the prevention of malignant lesions or tumour development. For example, there are indications that a diversification of the flora through the intake of fibre could encourage an increase in antineoplastic properties, in other words a greater capacity to slow down the proliferation of tumour cells".
In this regard, research carried out to date has revealed that this causal link is due to the fact that the microbiota can have a direct effect on the intestinal barrier3. This barrier acts as a filter between the body and the food and pathogens that enter the intestinal tract. Damage to this barrier can lead to tumor cells or other pathologies. However, in spite of these advances, specialists stress that further research is needed into the relationship between diet and the development and prognosis of colon cancer, since the current data is limited and comes mainly from preclinical studies.
Meanwhile, in accordance with standard clinical and patient guidelines, these studies continue to emphasise the importance of avoiding harmful habits, such as alcohol and tobacco consumption, and to recommend moderate-intensity exercise to help with the prevention of all types of cancer.