I'm asking because my GI specifically told me to refrain from red meat when I had my first colonoscopy four years ago (and subsequently had two precancerous polyps). I'm 20 with a family history and otherwise healthy. I've heard different things from different studies and would like to hear the Paleo consensus.
You'd see high cancer rates in populations such as the Hadza, but you do not. They boil most of their meat (but eat marrow raw, for what it's worth).
We've been eating red meat for literally millions of years. Red meat = food. "This just in: Food Causes Colon Cancer." I just don't buy it.
If you think about how the average person gets most of their red meat (fast food) then it becomes clear that other variables would interfere.
As I understand it, Colon cancer barely even existed until about 100 years ago, and this is one of those Hockey Stick type diseases whose frequency has skyrocketed. Red meat consumption may have gone up somewhat during this time, but I can't imagine it's even a strong correlation. As has been said, red meat is common throughout history, colon cancer is not.
Another recent study... Tabatebaei SM, Fritschi L, Knuiman MW, Boyle T, Iacopetta BJ, Platell C, Heyworth JS. Eur J Clin Nutr. 2011 Mar 2. [Epub ahead of print] Meat consumption and cooking practices and the risk of colorectal cancer.
Background/Objectives:The association between meat consumption and the risk of colorectal cancer (CRC) has been controversial. One of the difficulties in determining this association has been measurement of different attributes of meat consumption, including cooking methods and level of doneness.Subjects/Methods:We investigated the association between meat consumption and cooking practices and the risk of CRC in a population-based case-control study in the Western Australian Bowel Health Study. From July 2005 to February 2007, 567 incident CRC cases and 713 controls, who were frequency matched to cases for age- and sex, completed questionnaires on lifestyle and meat consumption. Estimated odds ratios (ORs) comparing meat consumption quartile groups were obtained from multivariate logistic regression models.Results:The amount of red baked meat consumed had a statistically significant inverse trend of association with CRC (Q4 OR=0.73 95% confidence interval 0.53-1.01). When frequency was multiplied by serving size and by doneness, the association remained protective but was no longer statistically significant. The protective trends for red pan-fried meat were also borderline statistically significant. There were no other statistically significant or meaningful associations with any of the types of meat cooked by any method and the risk of CRC.Conclusions:Our data do not support the hypothesis that meat consumption is a risk factor for CRC.
I heard a USC researcher give a talk on this back in 2007, which was good. Of course, she pointed out all the observational epidemiological studies we all know and debate on but she also went over some plausible mechanisms. These basically came down to carcinogenic compounds that are formed during fast, high-heat cooking. She may have mentioned the nitrate thing but I think the consensus on that is the proof there is severely lacking given that nitrates are broken down into NO far before they can form nitrosamines in the gut. Anyway, I think it's likely that high-heat cooking can generate various carcinogens, whether by fat dripping into flame or the charring of proteins, so I would consider that and prepare the meat by other methods (i.e. braising). I would not hang my hat on the blanket statement red meat causes cancer until there are RCT showing that and then showing that in the absence of the conditions I mentioned.
My thoughts on the subject are that the studies are done on people who eat traditional, grain-fed feedlot meats that you buy in the grocery store, as well as processed meats, typical in the modern diet. I don't know for sure how long Paleo has been around now, but surely less than a decade, and it's only grown in large numbers of followers in the past 5 years or fewer.
No studies exist at this point on a large-scale population eating grassfed and free-range meat only to discover if it's the type of saturated fat (high in Omega-6 grainfed vs high in Omega-3 grassfed), processing, cooking methods or other factors. As was stated, Colon Cancer has only been around in high numbers for the past 30-40 years, about the same amount of time we've been producing feedlot beef and artificially fattened poultry.
Until such a study is done and its results published, my intellect tells me that there's a huge difference in our health when we eat the meat we were designed to eat rather than feedlot meat, and that healthier meat is healthier for us and doesn't cause the colon cancer that feedlot meat does.
Colon cancer symptoms aren't always apparent, but you can understand what these signs overall look and feeling like. Knowing digestive tract cancer signs is essential, because you can use this information to work with your physician to find out the cause and manage your long-term health. Age—unfortunately, some risk factors are out of your management. Usually, specialists suggest that anybody, male or feminine, over the age of fifty be screened frequently, because the likelihood of colon cancer will increase with age. African American males are at slightly exaggerated risk of developing colon cancer , and therefore the advice for screening begins at age forty five for this population.Signs of colon cancer in your personal history—genetics play a giant role in determinant the probability that a patient are diagnosed with colon cancer . Genetic symptoms like familial adenomatous polyposis or hereditary non-polyposis body part cancer (Lynch syndrome) are sturdy indicators that a patient might be in danger. Those whose medical records embrace a history of body part polyps (even benign polyps) and different gastrointestinal complications like ulcerative colitis or inflammatory bowel disease (Crohn’s Disease) are inspired to urge tested at an earlier age.