Ok I know its in mice, but this is how research is done. I still believe I am right to give up red meat, although I also believe that sometimes a little of what you fancy does you good. But you know what – I find it hard to eat a steak (makes me gag – the last time I ate it was over a year ago) and even lamb sticks in the throat. Pork is better, especially cooked Far East style, and I have a few tasty recipes for you on this site!
Judge for yourselves:
Sugar Molecule Links Red Meat Consumption and Elevated Cancer Risk in Mice
Neu5Gc, a non-human sugar found in red meat, promotes inflammation and cancer progression in rodents
December 29, 2014 | Heather Buschman, PhD
In a study published in the Dec. 29 online early edition of the Proceedings of the National Academy of Sciences, the scientists found that feeding Neu5Gc to mice engineered to be deficient in the sugar (like humans) significantly promoted spontaneous cancers. The study did not involve exposure to carcinogens or artificially inducing cancers, further implicating Neu5Gc as a key link between red meat consumption and cancer.
“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.”
Varki’s team first conducted a systematic survey of common foods. They found that red meats (beef, pork and lamb) are rich in Neu5Gc, affirming that foods of mammalian origin such as these are the primary sources of Neu5Gc in the human diet. The molecule was found to be bio-available, too, meaning it can be distributed to tissues throughout the body via the bloodstream.
The researchers had previously discovered that animal Neu5Gc can be absorbed into human tissues. In this study, they hypothesized that eating red meat could lead to inflammation if the body’s immune system is constantly generating antibodies against consumed animal Neu5Gc, a foreign molecule. Chronic inflammation is known to promote tumor formation.
To test this hypothesis, the team engineered mice to mimic humans in that they lacked their own Neu5Gc and produced antibodies against it. When these mice were fed Neu5Gc, they developed systemic inflammation. Spontaneous tumor formation increased fivefold and Neu5Gc accumulated in the tumors.
“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.
“Of course, moderate amounts of red meat can be a source of good nutrition for young people. We hope that our work will eventually lead the way to practical solutions for this catch-22.”
Study co-authors include Annie N. Samraj, Oliver M. T. Pearce, Heinz Läubli, Alyssa N. Crittenden, Anne K. Bergfeld, Kalyan Banda, Christopher J. Gregg, Andrea E. Bingman, Patrick Secrest, Sandra L. Diaz and Nissi M. Varki, all at UC San Diego School of Medicine.
This research was funded, in part, by the Ellison Medical Foundation, the National Cancer Institute (grant R01CA38701), a Samuel and Ruth Engelberg Fellowship from the Cancer Research Institute and a Swiss National Science Foundation Fellowship.
Disclosure: Ajit Varki and Nissi Varki are co-founders and have equity interest in SiaMab Therapeutics, Inc., a biotech company with an interest in Neu5Gc and anti-Neu5Gc antibodies. In addition, Ajit Varki is a member of SiaMab Therapeutics, Inc.’s Board of Directors and is a Scientific Advisor to the company. The terms of this arrangement have been reviewed and approved by the University of California, San Diego in accordance with its conflict of interest policies.
Thanks for sharing this. I wanted to be sceptical but found it interesting. Like you, I’m not going to completely avoid red meat, but I will keep frequency and portion size down.
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Apart from anything else, I think it helps with weight loss, cholesterol and all those other things we ‘survivors’ are keen on! It’s like the alcohol – weekends only is fine and the less you have the less you want. All good stuff!
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Yes and as you said Vicky, grass fed animals. We just got an order from a farm recommended by the nutritionist.
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Still caution moderation!
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Don’t eat that much, sorry the point I was making is that according to the nutritionist at The Haven, a charity run for breast cancer patients, you don’t have to cut it out completely.
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Yes I understand thats what she says but research seems to caution moderation…I have to eat liver occasionally as I have B12 deficiency and I do eat pork (as I saw you looked at one of my recipes!) but in Chinese Medicine pork seems to be a neutral meat, so perhaps thats a good cheat! Its hard to know WHO to believe to be honest…
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It’s very complex. I am a nutritionist and a seventeen year ‘survivor’ so I’ve been thinking and blogging about this for a long time. There are so many factors to consider, not least how long the meat fibres, once swallowed, stay in your gut and ferment. Bowel frequency is a key factor in bowel cancer and too much meat consumption can slow things down, especially when combined with grains. Grass fed meat is better in many ways, not just because it has a better fat profile with more polyunsaturated omega 3 fats, but also because the opposite – grain fed meat – contains compounds that shouldn’t ‘naturally’ be there. So one of the questions I ask – but which the research doesn’t clarify – is would this pro-inflammatory sugar even be in the meat if the animal had been raised organically? See what I mean? It’s complex. So much to know, not enough space or time to write it all. It’s a journey. I have been eating red meat in moderate levels throughout my survival time. But I do eat organic, and what suits me it doesn’t suit everyone.
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