In the past, red meat consumption has been linked with many diseases, such as colorectal and breast cancers amongst many other. And while it has been strongly associated with higher risk of cancer in humans, as opposed to other animals, the mechanism for the meats' health risk have not been determined. But a recent study published this week in the journal Proceedings of the National Academy of Sciences may have just discovered the science behind its carcinogenic effect, particularly in humans.
Researchers at the University of California, San Diego's School of Medicine found that a sugar specific to red meat may be the cause of malignant tumors forming in the human body. The foreign sugar is called Neu5Gc, which the researchers had previously found to be absorbed into human tissues. Neu5Gc is found to trigger an immune response from the system, producing antibodies which spark inflammation, and eventually cancer.
The study involved mice which were engineered to be Neu5Gc-deficient. The researchers found that mice fed the said sugar experienced systemic inflammation, which was associated with a fivefold increase in spontaneous tumor formation.
"Until now, all of our evidence linking Neu5Gc to cancer was circumstantial or indirectly predicted from somewhat artificial experimental setups" lead researcher of the study, Dr. Ajit Varki, professor of Medicine and Cellular & Molecular Medicine, says. "This is the first time we have directly shown that mimicking the exact situation in humans increases spontaneous cancers in mice."
The researchers believed that Neu5Gc may strongly be associated with increased cancer risk, though they did not expose the mice to other carcinogens.
"This work may also help explain potential connections of red meat consumption to other diseases exacerbated by chronic inflammation, such as atherosclerosis and type 2 diabetes," Varki says. "The final proof in humans will be much harder to come by."
"Of course, moderate amounts of red meat can be a source of good nutrition for young people, making it a 'catch-22'".
