Another Reason Why Red Meat Is Bad for You

By Sondra Forsyth

Researchers have found that eating red meat, already known to be a bad health habit, may also introduce a tumor-forming substance into the body.

The discovery was made by researchers from the University of California, San Francisco and was published in the Proceedings of the National Academy of Sciences.

The scientists focused on the possibly deadly role of a sugar called Neu5Gc, which is naturally found in most mammals but not in humans. After feeding Neu5Gc to mice that had been genetically altered to lack the sugar in the same way humans do, the investigators found that the sugar significantly promoted “spontaneous cancers.”

“Until now, all of our evidence linking Neu5Gc to cancer was circumstantial or indirectly predicted from somewhat artificial experimental setups,” said principal investigator Ajit Varki, MD, Distinguished Professor of Medicine and Cellular and Molecular Medicine and member of the UC San Diego Moores Cancer Center. “This is the first time we have directly shown that mimicking the exact situation in humans — feeding non-human Neu5Gc and inducing anti-Neu5Gc antibodies — increases spontaneous cancers in mice.”

In earlier studies, the researchers had discovered that animal Neu5Gc can be absorbed into human tissues. And in the latest study, the team found that the sugar led to inflammation. According to a university news release, “Chronic inflammation is known to promote tumor formation.”

“The final proof in humans will be much harder to come by,” Varki said. “But on a more general note, 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.