These include red meat’s high fat content and heme iron, nitrates and nitrites added to red meat, and compounds produced by gut microbiome or during cooking. This study suggests another explanation for red meat’s adverse effects.
Red meat and dairy all contain a compound called Neu5Gc (short for N-glycolylneuraminic acid). The study persuasively suggests that Neu5Gc is a key factor in the development of colorectal cancer, breast cancer, and heart disease.
Neu5Gc is a carbohydrate that is present in many of the mammals we eat as food (e.g., cows, pigs, and goats). However, it is not found naturally in humans. When ingested, Neu5Gc is perceived as a foreign invader. This results in an inflammatory reaction to the presence of Neu5Gc.
In this study, investigators looked at a large cohort of over 19,000 adults over the age of 18. They calculated daily Neu5Gc intake, and measured anti-Neu5Gc antibodies in 120 representative subjects.
The researchers found higher levels of antibodies against Neu5Gc in those who had a high daily Neu5Gc intake. They postulate that the higher antibody levels could cause the elevated cancer risk in those who eat a large amount of red meat.
There is extensive evidence in mice regarding the role of antibodies against Neu5GC. These antibodies seem to cause inflammation, which leads to a variety of chronic diseases. The authors emphasize that current evidence does not support Neu5Gc as a direct causative agent but rather one that contributes to the promotion and worsening of such diseases.
In the simplest of terms, a foreign animal carbohydrate – Neu5Gc – creates an antibody reaction because this non-human carbohydrate is perceived as a foreign substance. The process of antibodies attacking the foreign Neu5Gc causes inflammation, which can result in colorectal cancer, breast cancer, and heart disease.