For the first time, researchers from the University of California, San Diego's School of Medicine were able to link a sugar molecule called Neu5Gc to the consumption of red meat and cancer in a study. Previous evidence has been circumstantial, but now there's solid proof that eating red meat increases risks of developing cancers.

Published in the journal Proceedings of the National Academy of Sciences, the study showed that feeding mice that are deficient in the sugar molecule (like humans) Neu5Gc dramatically caused spontaneous cancers. The mice were not exposed to artificially induced cancers or carcinogens so Neu5Gc is seen to be key link connecting red meat consumption with cancer.

Researchers first carried out a systematic survey involving common food items. They identified lamb, pork and beef to be high in Neu5Gc, confirming that red meat is rich in the sugar molecule. Neu5Gc is also bio-available, meaning it can easily find its way all over the body through the bloodstream.

The study was built on the hypothesis that consuming red meat leads to inflammation. This is because when Neu5Gc gets lodged in body tissues, the immune system recognizes the sugar molecule as a threat, producing antibodies to counter it. Repeated consumption of red meat then will cause chronic inflammation, which has been known to increase risks of tumor formation.

"The final proof in humans will be much harder to come by. 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," said Ajit Varki, M.D., a part of the UC San Diego Moores Cancer Center and principal investigator for the study.

While eating red meat has its risks, researchers don't discount the fact that it can also be a good source of nutrition. Moderation is key if people want to reap the benefits of consuming red meat without exacerbating their risks for cancer. Researchers hope that the results of the study can help in the development of a practical solution for the problem that is red meat consumption.

The study received funding support from a Swiss National Science Foundation Fellowship, the Cancer Research Institute's Samuel and Ruth Engelberg Fellowship, a National Cancer Institute grant, and the Ellison Medical Foundation.

Co-authors for the study include: Nissi Varki, Sandra Diaz, Patrick Secrest, Andrea Bingman, Christopher Gregg, Kalyan Banda, Anne Bergfeld, Alyssa Crittenden, Heinz Laubli, Oliver Pearce and Annie Samraj.