Liza: Why did you leave out this part?: [Snip] But much research has focused on the fat content of animal fat or byproducts of cooking meat as the cause of disease. Varki's collaborator Dr. Elaine Muchmore developed an antibody -- an immune system targeting protein -- that would hook onto Neu5Gc. The team found Neu5Gc in human tumor samples and to a much lower degree in healthy tissue. More tests showed that most people had made their own antibodies that recognized Neu5Gc, and thus could potentially initiate an inflammatory immune response. Varki and two colleagues drank Neu5Gc purified from pork sources, and the molecule showed up in their urine, blood, hair and saliva. "We need to find out if there is any association between the presence of Neu5Gc and/or the anti-Neu5Gc antibodies with any disease," Varki said. "This will require large-scale population studies." In some cases the human immune response was similar to that seen when people are exposed to another animal molecule, this one a cell surface molecule called alpha galactose. Varki noted that the molecule is almost certainly not immediately toxic to people. "Meat eating has certainly been a feature of human ancestors for many hundreds of thousands of years," he said. "Thus, it is indeed possible that humans have developed some kind of tolerance or indifference to Neu5Gc. However, most humans are continuing to make antibodies against Neu5Gc." It could be that the damage only builds up over years -- and that as people live longer, the consequences make themselves felt. "However, we are now living longer and the question arises whether the gradual accumulation of Neu5Gc and the simultaneous presence of antibodies against could be involved in some diseases of later life," he said. [snip] Basically, the research is interesting but inconclusive. However, snipping it where you did seemed designed to play up the case against meat and down-play the uncertainties the researchers expressed. Tumors contain a lot of molecules. As they said, large scale studies and research on possible mechanisms would have to be done to show any firm causitive link between this Neu5Gc and cancer. So far its just a tenuous link and speculation. The authors make the common mistake of assuming that all people in the past lived shorter lives than we do. They like others confuse average life expectancy, which is reduced by early deaths, and actual individual life spans. Socrates, Plato, and Aristotle all lived past 70, more than 2000 years ago. Socrates you know may have lived longer but was put to death. In the McDougall article that was discussed here last week the same mistake. To distill it: The average life expectancy is based on averaging all deaths. So if you have 5 people die in their first year of life (infections), 5 die at an average age of 35 from hunting accidents, and 5 live to 70, the average life expectancy of this group will be calculated to be 35 years of age. Yet 33% of the people lived to 70. This is an oversimplification of how stats are misunderstood to make it look like all pre-industrial people died at 35. McDougall made the more remarkably misguided statement that you only have to live to 20 to reproduce. If he means just popping out a baby he has an incomplete view of reproduction. Most people understand that infants are not self-sufficient. In fact, it takes about 16 years to truly reproduce oneself in a child, i.e. get him/her to the point of true self-sufficiency. Because of the long dependency period in humans, I find it difficult to imagine any human group surviving long if all members died at 30 or so. Weston Price and Stefansson searched for cancer among primitives without success although many ate large amounts of animal products and lived to advanced ages (as documented by the photos in Price's book). Moreover, U.S. cancer rates have skyrocketed since 1900 in America, but average red meat consumption has actually slightly declined according to USDA figures. These researchers are suggesting poultry is safer, but over the past century in the U.S. chicken consumption has gone up. And these days cancer is growing in prevalence in young people, so the meat+aging hypothesis seems to be leaking from the start. Don