I’m sure you saw the headlines this week about a new report from the American Institute for Cancer Research and the World Cancer Research Fund. The report covered a variety of factors that appear to increase risk of colorectal cancer, including alcohol, processed meat, and excess belly fat, as well as things that appear to decrease the risk, including exercise, garlic, milk (but not cheese), calcium, and foods containing fiber. However, most of the headlines I saw were along the lines of “It’s Official: Red Meat Causes Cancer.”
As long-time followers know, I’ve long been suspicious of the science on “red” vs. “white” meat. See, for example: Red Meat: Not so Bad After All?
Having now read the latest report in its entirety, I want to highlight a few nuances that may help you decide how–or whether–to change your eating habits based on this latest indictment of red meat.
How Much Red Meat Do You Eat?
As usual, the dose makes the poison. The people who experienced the most dramatic increase in risk were those eating a half a pound of red meat every day. People who eat less than a pound of red meat a week are at little to no increased risk. Researchers have a theory about why this is the case.
Red meat contains the heme-form of iron. Poultry and fish also contain heme iron; the iron in vegetables is a non-heme form. Iron is an essential nutrient, of course, and the heme form of iron is the most bioavailable form of the mineral. But too much heme iron in the gut can promote the formation of potentially carcinogenic compounds. The fact that red meat is a richer source of iron than white meat could explain why consumption of red meat in large quantities is associated with increased colon cancer risk, while eating poultry, fish, or moderate quantities of red meat is not.
In other words, if you eat red meat once or twice a week (or, like me, once or twice a month), you have nothing to fear.
Do You Eat Vegetables?
The formation of those potentially carcinogenic compounds is largely blocked by the consumption of antioxidant rich fruits and vegetables, by the way. And, indeed, higher consumption of these foods decreases risk of colon cancer.
As is so often the case, when you’re looking at the link between foods and diseases, you really need to look at the entire dietary pattern and not just individual foods or nutrients. Someone who eats plenty of red meat but also plenty of vegetables would appear to be in a completely different risk group than someone who eats plenty of red meat and very few vegetables.
In other words, ounces per day of red meat doesn’t tell the whole story.
How Do You Cook Your Meat?
The other (and in my mind, stronger) theory about why red meat is linked to colon cancer has to do with the formation of heterocyclic amines (HCAs) and polycyclic aromatic hydrcarbons (PAHs) that form when red meat is cooked over direct flames or high heat, such as a char-broiled steak. However, simply marinating that steak for 30 minutes before throwing it on the grill can reduce the formation of harmful compounds by up to 90%. For more ways to reduce the formation of HCAs and PAHs, see: Tips for Healthier Cookouts
So, how will this latest report (or anything I’ve said here) impact your food choices?
“too much heme iron in the gut can promote the formation of potentially carcinogenic compounds”
Has this been observed in vivo, or is it extrapolated from the test tube?
For that matter, is there any evidence from controlled (non-observational) studies to indicate a causal connection between red meat consumption and colorectal cancer? I haven’t read the report in detail, but a quick scan through uncovered this gem:
“Due to the large number of cohort studies, analysis and interpretation of case-control studies was not included in the Continuous Update Project Report.”
Doesn’t exactly inspire confidence in the judgment of the authors (not to mention that they misspelled “judgment” throughout the paper).
“Judgement” is an accepted alternate spelling.
Well, my spell-checker flags “judgement”, but whatever (when my daughter was 2, “jujjmint” would have been an accepted alternate spelling as well).
The more salient point here is that they seem to be arbitrarily excluding the stronger case-controlled evidence, and presenting us with “judgements” based on the subset of evidence that they selected. Pretty smelly, particularly considering that there exist well-established methods for including and quantitatively weighting different forms of evidence like this. Maybe they skipped that day in school, probably off having a 0.51-lb burger.
And yet again, a US American is eager to show his ignorance.
Yes, I regret having picked on the spelling of “judgment” here. I allowed my annoyance at the completely unscientific judgement in the report to colour my own judgement 😉 I’ve since enlightened myself a bit on the origins of the spelling difference. Noah Webster didn’t think much of the king or his English, did he?
Wow, bigot much?
This sounds a bit more sane from the abstract, like they did some actual statistical analysis – too bad it got little media coverage.
http://onlinelibrary.wiley.com/doi/10.1111/j.1467-789X.2010.00785.x/abstract#_jmp0_
I’ve noticed that things that validate and reinforce my own convictions usually seem saner and sounder to me!
You seem to be under the impression that I am defending or endorsing the AICR report . I’m not sure why. As I said above, I’ve long been suspicious of the science on red vs. white meat. (http://www.self.com/fooddiet/blogs/nutritiondata/2009/04/meat-and-mortality-whats-color.html)
I’ve done my part to publicize studies finding no relationship between red meat and colon cancer. http://www.self.com/fooddiet/blogs/nutritiondata/2010/11/red-meat-not-so-bad-after-all.html)
And, as I conclude in this post, having examined the details of the AICR report, it seems reductive (at best) to conclude that red meat per se causes colon cancer.
So, what’s your beef, Dave? (groan….)
I think you read to much into my comment. My criticism was aimed at the report, not at you. I didn’t say nor was I trying to imply that you endorsed it, just giving some alternate information for your readers. Sorry if that wasn’t clear. I more or less agree with your original article, and my first question on heme iron was really just curiosity, not a challenge.
So I’ve got no beef with you on this point. The only beef I’ve got right now is the 1-lb. burger I ate for dinner last night. And I’m not in the least bit worried about getting colorectal cancer from it 😉
And while we’re on the topic, here’s an excellent analysis of the statistics around the question:
http://www.fathead-movie.com/index.php/2011/05/26/the-lastest-meat-causes-cancer-bologna/
Wow, a study funded by the Beef Checkoff through the National Cattlemen’s Beef Association that finds no link between cancer and beef consumption.
What a surprise!
You question the judgement of an international team of over 2o researchers (according to the acknowledgments section of the report, with members from the USA, UK, Chile, France, and Sweden), working for the World Cancer Research Fund and the American Institute for Cancer Research, but have absolutely no problem accepting the conclusions of 2 researchers funded by the beef industry? How can that be possible? Seriously doesn’t make any sense to me at all.
What counts more: the number of authors on a paper and their affiliation, or the evidence supporting the hypothesis?
The evidence supporting their hypothesis, of course. But not being qualified to make that determination myself, (i.e. who’s evidence is stronger), I’d go with the two organizations whose motive is to prevent and control cancer over research that has been funded by an obvious biased industry. Unless you have actually compared both studies side by side and are qualified to make judgements on whose evidence is strongest, why would you chose any differently?
How do you know the “experts” are qualified to make a determination if you don’t know at least enough about the subject to know which “expert” is really an expert?
How do you know the motives of the organization who published this report? Who funds them? And why did they leave out controlled studies (which AFAIK generally show no significant relationship between red meat and cancer) in favor of observational studies (which show a weak relationship between cancer and red meat, along with a pile of other things)?
To your question will this change the way I eat? I have a grilled steak 1-2x a month and maybe as many servings of beef in other forms throughout the month. I won’t change that. I will marinate my steaks now to offset the potential HCA and PAH production.
Oh yeah, and lots of vegetables too!
What does ‘plenty’ mean in the context of ‘plenty of meat’ and ‘plenty of vegetables’?
Iron is an important factor in the growth of many types of bacteria. I read a review article once discussing several studies correlating iron levels to susceptibility to infection with pathogenic bacterial strains. I wonder if that could possibly play a role.
According to Ned Knock,
“the effect of red meat on cancer “disappeared” when obesity was included as a competing independent variable, suggesting that obesity is a confounder that must always be controlled for in this type of study”
Thanks for this enlightening article. Now we’ve found ourselves something that has been hiding itself from the media. There’s always another perspective in every aspect, it’s either we find them or we don’t. Search and search till we do!
“The people who experienced the most dramatic increase in risk were those eating a half a pound of red meat every day. People who eat less than a pound of red meat a week are at little to no increased risk. ”
Don’t you mean 1/2 lb (or ~500grams) per week? Not day.
From the study:
Red and Processed:
“CUP meta-analyses (per 100g/d) for colorectal, colon and rectal cancers showed 16, 21 and 31 per cent increased risk respectively (see CUP figures 47, 51 and 55).
The SER meta-analyses (per 100g/d) that showed a 37 per cent increased risk for colon cancer (SLR figure 5.2.123).
A published meta-analysis of highest versus lowest intakes of red and processed meat of 13 407 cases from 33 risk estimates showed a significant increased risk (21 per cent for colorectal cancer(34). A published dose response meta-analysis of 7367 cases from 14 studies showed a 28 per cent increased risk per 120g/day increase in red and processed meat(60).”
Red Meat Specifically:
CUP meta-analysis (per 100g/d) showed a 17 per cent increased risk for colorectal cancer (see CUP figure 70). Summary estimates from CUP meta-analysis were in the direction of increased risk for colon and rectal cancers, but did not reach statistical significance. The SER meta-analysis (per time per day) that showed a 43 per cent increased risk for colorectal cancer (see SER figure 4.3.2). The CUP meta-analysis showed less heterogeneity (I2 =0 vs. 58 per cent) for colorectal cancer than those in the SER.
Processed Meat Specifically:
CUP meta-analysis (per 50g/d) showed an 18 per cent increased risk for colorectal cancer and a 24 per cent increased risk for colon cancer (CUP figures 58 and 62). The summary estimate from the CUP meta-analysis for rectal cancer was in the direction of increased risk but did not reach statistical significance (CUP figure 66).
The SER meta-analysis (per 50g/d) showed a 21 per cent increased risk for colorectal cancer (see SER figure 4.3.6).
Also, I think it reasonable to assume degrees of risk as red meat consumption decreases. To say that those consuming less than 500g per week are at little to no increased risk does not seem accurate. For example, if 50g/d of processed meat increases risk by 21%, then someone who eats 45g/d would be at less risk in comparision, but would still have an increased risk over someone who eats only 30g/d, who would be at an increased risk over someone who eats only 20g/d, and so forth. I don’t think there is a magic cutoff where if you eat 500g/d you have a increased risk, but if you eat 499g/d or less, you are perfectly fine.
Thanks for the questions and comments. The paragraphs you are citing here refer the increase in risk per increment (g/day) but don’t represent the overall relative risks. In a news release that accompanied the full report, the investigators who crunched the numbers summarized the data this way:
As to your “reasonable assumption”, a dose-response relationship (in which the risk goes up with dosage) is a key piece of evidence in strengthening the case for a causal link. However, that relationship is rarely linear (which is what you’re suggesting here). Very frequently, there is no significant increase in risk below a certain threshold of exposure.
And unless the dose-response relationship is observed either in a controlled study, or completely overwhelms other observed relationships, you can’t make much of a case for causality. More accurately, you can’t make a case that, say, red meat caused the increase in cancer as opposed to any of the hundreds (thousands) of other variables inherent in the sort of observational studies that were included in this analysis (remember that they deliberately excluded the case-controlled studies).
Relative risk is also a misleading number. Let’s compare with smoking. According to our government (http://www.smokefree.gov/smokersrisk/about.asp), if I am a current smoker started smoking before 18, smoked 11-19 cigarettes per day, and am now between 40-44 years of age, compared to a non-smoker I have a 14x higher risk of lung cancer by age 75-79, i.e. 1300% higher than that of a non-smoker (risk went from 1% to 14%). In other words, 1 out of 100 non-smokers contract lung cancer by 75-79, while 14 out of 100 smokers with the parameters above develop lung cancer by the same age.
Now I eat a lot of red meat, generally at least 7 ounces per day. According to the analysis in the report, my relative risk is 34% higher. I believe the current absolute risk for colorectal cancer is something like 1 in 20, so on average 5 out of 100 people will get this disease. The “back of the envelope” calculation thus implies something that for those eating a lot of red meat, 6.7 out of 100 will develop colorectal cancer, on average extra 1.7 more people per 100.
So we have a small effect, and one apparently seen only in observational studies with large numbers of uncontrolled variables. If we look at the same data, how does the relative risk of colorectal cancer change with refined carbohydrate consumption? Vegetable oils? Grains? They probably all show a similar effect, because the consumption of all of these things tends to be highly correlated in “civilized” populations (think fast food, processed food). Observational data was able to point to a link between cigarette smoking and disease because it was a large independent effect. Here we’re looking at diet and lifestyle, with many interacting components both environmental and biological. Is there now (and was there ever) any reason to favor the red meat hypothesis over the myriad other possibilities? As far as I know (and I am far from an expert), any connection between red meat and cancer disappears when tested under more controlled circumstances. And while one can find potential carcinogenic scenarios for red meat in the test tube, you can do the same for a wide variety of foods. These things often tend to not have similar effects in living organisms, which evolve mechanisms to neutralize the wide array of potential disease-causing substances and organisms in their food. Humans and human ancestors have been eating red meat (grilled, no less) for hundreds of thousands of years. I think I’ll just avoid cigarettes and fast food, and continue to enjoy my steak.
According to the AICR press release, following these guidelines could prevent 64,000 cases per year. While I do not know how many of these would be attributed to cutting down on red and processed meats, it certainly seems over a large population even small changes in risk can make a big difference.
If researchers cannot separate out the effects of red meat and processed meats from other variables like refined carbohydrate and vegetable oils, then I think it would be prudent to warn consumers against a dietary pattern that includes these foods, even if at the end of the day a food that could not be tracked independently ended up not increasing risk. What would be the alternative? Observing a greater risk as a result of this dietary pattern, but because researchers cannot be certain the increased risk is a result of only red meat or processed red meat, or only vegetable oils, or only refined carbohydrates, or some combination, don’t bother warning the public of a possible link between consumption of these foods and cancer? That doesn’t make any sense to me.
I suppose the reason researchers zeroed in on the red meat hypothesis is because that is where the science led them. When they first started tracking disease occurence in relation to diet red meat must have stood out enough for researchers to take notice.
You are right that most studies researching the link between diet and disease are observational and do not include controls. This is probably due to the desire to study large groups over long periods of time. But a quick scan through pubmed did uncover a couple of studies that were more controlled in nature.
http://www.ncbi.nlm.nih.gov/pubmed/19640186
http://jnci.oxfordjournals.org/content/100/14/996.short
http://www.ncbi.nlm.nih.gov/pubmed/17761300
http://www.ncbi.nlm.nih.gov/pubmed/17354224
http://www.ncbi.nlm.nih.gov/pubmed/14639617
http://www.ncbi.nlm.nih.gov/pubmed/12615608
http://jn.nutrition.org/content/132/11/3522S.short
http://www.ncbi.nlm.nih.gov/pubmed/9383789
http://carcin.oxfordjournals.org/content/17/3/515.abstract
Anyways, not sure if these meet your criteria for more controlled conditions. Cooking method seems to be important, which I don’t think was discussed in the report under discussion.
I agree that humans have been eating red meat for hundreds of thousands of years, but I disagree that we can use that as evidence that red meat is a good food to incorporate in our diet. A lot has changed in our lifestyle (for example, I am pretty sure as a whole we are much more sedentary than our ancestors living a hundred thousand years ago), and while they were concerned only with eating whatever was available and living 30-40yrs (at best), we have a vast array of foods to chose from year round and would like to be alive and healthy well into our 90’s and beyond.
For what it’s worth, the report does talk a bit about cooking method. In discussing the likely mechanism by which increased mechanism might increase colon cancer risk, they have two ideas: 1) higher intake of heme iron 2) higher intake of carcinogenic compounds created during heat temperature cooking (such as grilling). With processed meat, there is the added mechanism of nitrosamines created from the nitrates used to cure the meats.
Great discussion, by the way. Thanks for the thoughtful contributions (from both “sides”).
Thanks for the links, I’ll check them out. You get bonus points for even providing links to research. Usually my request for this is met with dead silence.
“following these guidelines could prevent 64,000 cases per year”. Note “could”, which also implies “might not”. Brushing your teeth with your left hand “could” also prevent cancer, maybe just a little bit. I always think that expectation values were what Disraeli was thinking about when he made his famous quote about lies, damned lies, and statistics. Is it 64000+/-100, or 64000+/-100000? There’s a difference, particularly in terms of how you use that information to make decisions.
“I suppose the reason researchers zeroed in on the red meat hypothesis is because that is where the science led them. When they first started tracking disease occurence in relation to diet red meat must have stood out enough for researchers to take notice. ”
You suppose? Or you know? That’s a weighty prior in terms of assessing the evidence. I was a professional researcher (in astrophysics) for about 10 years. I walked in the door with similar preconceptions about the scientists’ noble pursuit of truth. I walked out with a radically different view, namely that scientists are just as biased and irrational as the average guy on the street (in retrospect, something which should have been obvious from the get go). Your reasoning carries with it a major assumption, which is that the report authors are not (intentionally or unintentionally) biased, and have some significant quantitative evidence to back up their conclusions. Since they left out the case controlled studies such as what you linked, it is unlikely they have such. For a little quantitative analysis, see the Fat Head link I posted above.
Methods exist to quantitatively compare hypotheses given the available evidence. These require no judgment on the part of the person doing the analysis, and where some subjective information is injected, it can be done so with transparency. Said methods also allow for various sources of evidence (e.g. observational and controlled studies) to be combined, even including evidence on putative causal biochemistry. The AICR/WCRF report is a lot of hand-waving for me. And the real question: was there ever really any evidence to connect red meat and disease in the first place? Or did it just become entrenched as dogma, in which case a “scientific report” such as we are discussing takes on far more psychological weight than justified by the evidence?
Agricultural peoples definitely had considerably greater physical activity, and adult lifespans usually not lasting past 30 or 40. Hunter-gatherers were only moderately active (though no doubt more so than modern people). They had high infant/child mortality rates from disease and accidental death, so the mean lifetime was around 35; but if you made it past puberty there was about as good a chance of living until 70 as exists today. There is a popular assumption (also popular amongst scientists who should know better) that reproductive fitness only applies to the reproductive lifetime of an individual. That’s true for something simple like a worm, but humans are social animals. I wouldn’t discount the survival value of having Grandma and Grandpa around while Mom and Dad were off killin’ and grillin’. That people can and do routinely live well past their reproductive years in “primitive” societies would indicate some evolutionary value. Otherwise all of the resources they use would seem to be better employed for making more babies.
Anway, I’ll stick with my steak and butter. I’m healthier eating that way than I was for any other regimen I tried, including a stint of being a vegetarian and working out about 8 hours a week. Let’s meet up at 90 and compare notes 😉
Interesting discussion of nitrosamines (and other things bacon-related) here:
http://balancedbites.com/2011/05/bacon-health-food-or-devil-in-delicious-disguise.html
I have a feeling the WCRF reasoning on cooking methods etc. is missing the relevant link demonstrating an effect in living organisms.
“How do you know the “experts” are qualified to make a… ”
I am not qualified because I have not (and don’t intend too) critically scrutinized both reports to try and determine which one is the better representation of the facts. That said we have two reports offering up competing answers to the same question, and I am more inclined to believe the non-profit organization over the for-profit organization hired by an industry with a serious stake in the results of the study. Below are some studies discussing this issue.
http://jama.ama-assn.org/content/290/7/921.abstract
http://jama.ama-assn.org/content/295/19/2270.abstract?sid=90a6e53f-2d2a-432d-8dc9-35dd3a447b4a
http://www.ncbi.nlm.nih.gov/pubmed/12533125
http://www.ncbi.nlm.nih.gov/pubmed/14970094?dopt=Abstract
http://www.ncbi.nlm.nih.gov/pubmed/3772583
http://www.bmj.com/content/325/7358/249.full
http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.0040005
Based on the above I think I am justified in being more skeptical of your study than the WCRF study. It also helps that the red/process meat and colon cancer link is also endorsed by other health agencies:
World Health Organization: http://www.who.int/cancer/prevention/en/
American Cancer Society: http://www.cancer.org/Healthy/EatHealthyGetActive/ACSGuidelinesonNutritionPhysicalActivityforCancerPrevention/acs-guidelines-on-nutrition-and-physical-activity-for-cancer-prevention-diet-activity-cancer-risk
Health Canada: http://www.colorectal-cancer.ca/en/just-the-facts/risk-factors/
(Note: I am from Canada, so included my local health agency).
Also meaningful to note that your study only included prospective studies, thus also eliminating case-control studies from their summary as well.
As to why did the WCRF not include the controlled studies, I don’t know. According to their website and the report, the Continuous Update Database is still being built and won’t be completely up to date until 2015, guess we will see in a few years if those studies are added to the report or not.
“following these guidelines could prevent 64,000 cases per year…”
The figure is from the AICR press release based on the findings of their study, which indicates that if their recommendations were followed 45% of colon cancers cases would be avoided. Apparently that equals 64,000 cases. I have no idea what the margin of error is.
I have no idea how or when the red meat hypothesis was born. That was just a guess from someone who does still believe in the scientific method, even in this field and even with all the opposing forces and personal bias. If the WCRF conclusions are wrong then that will eventually be borne out, if not, then the evidence will continue to mount in favour of a link between red/processed meats and colon cancer.
“Let’s meet up at 90 and compare notes..”
You bet.
“I have not (and don’t intend too) critically scrutinized both reports to try and determine which one is the better representation of the facts.”
By all means, avoid critical thinking, or even examining the facts. It’s clearly much better to rely on the “consensus” of “experts” than to think for yourself.
If you allow others to think critically and make decisions for you, you will be serving their interests. If you’re lucky, their goals might have some alignment with your own, but don’t count on it.
“I am justified in being more skeptical of your study than the WCRF study”
For all the effort you’re putting in to find evidence of which evidence you should believe, you could just be looking at the relevant evidence for the matter at hand, rather than trying to figure out “who to believe”. And that’s not how scientific inference works. At it’s root,inference is just mathematics, not people arguing with each other. You don’t look at two studies and pick one, but rather consider them together. It’s like trying to figure out if a coin is fair or not. If you flip the coin and get 99 heads, you don’t just forget that if the 100th flip is a tail and declare it fair. It’s just math, not opinion.
“the evidence will continue to mount in favour of a link between red/processed meats and colon cancer.”
This has been studied for decades, and the evidence doesn’t appear to be mounting at all. Instead it continues to be a weak association, most easily seen in more uncontrolled studies (compare with the smoking/disease connection, where evidence really did grow over time). A similar situation existed around saturated fat for decades. “Everybody knew” that saturated fat caused heart disease, etc. Yet nobody could identify an actual biological mechanism in humans, and again the evidence really only appeared as weak associations in observational studies. Yet science soldiered forward, convinced that it would eventually find the evidence to support what it knew to be true (which begs the question of how everybody got so convinced in the first place, if they still needed to uncover the evidence). The problem was that almost nobody considered the hypothesis that the whole saturated fat thing was a red herring (or if they did, they kept it to themselves, because to do otherwise would have been career suicide). 50 years later, they’re finally figuring it out.
Science is littered with examples like this, far more the rule than the exception. Here’s an example I used in my blog (http://sparkofreason.blogspot.com/2008/04/cognitive-dissonance-and-scientific.html). Back in the day, physicists “knew” that all of space was permeated by a substance called “luminferous aether”. The aether had amazing physical properties, and was assumed to exist, because otherwise there was no way for light waves to propagate in a vacuum. To suggest that aether didn’t exist would have earned you great ridicule. Now, if only somebody could do the experiment to get the actual evidence of it’s existence.
Of course, as it turned out, those experiments never showed anything, and ultimately led to the development of Einstein’s Theory of Special Relativity. What “everybody knew” to be true was eventually swept away by actual evidence, but again, it took decades.
Sound familiar?
Interesting blurb from the book “Good Calories, Bad Calories”:
“By 1980, this link between cancer and low cholesterol was appearing in study after study. The most consistent association was between colon cancer and low cholesterol in men. In the Framingham Study those men whose total cholesterol levels were below 190 mg/dl were more than three times as likely to get colon cancer as those men with cholesterol greater than 220; they were almost twice as likely to contract any kind of cancer than those with cholesterol over 280 mg/dl.”
The 3x relative risk described here (with the caveat that it is still observational association, not clinical evidence) seems a lot more relevant than the 1.34x worst-case described by the AICR/WCRF. Anybody want to venture a guess what they had to say about this in their report?
Okay, you win. The WCRF study isn’t as strong as it was made out to be, largely due to the weaknesses inherent in observational studies and the low RR.
Hopefully you are right and no link exists, as pretty much everybody I know eats plenty of red meat.
Cheers
The world (and now the internet) is full of thousands of studies with competing results. We will always be able to find those which support what we already believe or hope to be true. But there IS a reason that red meat has been at the top of the American Cancer Society’s dietary recommendation pyramid for decades.
Great – it sounds like you have the answer we’ve been looking for. So what is the reasoning behind the ACS recommendation?
Dave,
I know this will disappoint you, but you were not my intended audience for that comment. Some facts just speak for themselves, and I just wanted to give some perspective to those who might stumble upon this thread in search of meaningful advice about diet related disease such as cancer. (Not intended for you because you cannot even concede that industry-sponsored research should not carry the same weight as decades of multi non-profit and non-industry-sponsored research. My guess is that either your livelihood is connected somehow to the meat industry, or you just REALLY love your burgers.) 🙂
And, because some facts just speak for themselves, I will not try to reinvent the wheel here. The connection between meat consumption and disease is a very well-established one. I have neither the time nor the wherewithal to play the copy and paste game with you.
Here is a good little page to look at for anyone wanting a quick snapshot of what is known about meat and dairy consumption as it relates to human health (from a Pulitzer prize nominated book on the subject):
http://www.hotspotzone.com/Vegan/facts.htm
Also, I know that anecdotal evidence has traditionally not held much weight in the field of scientific reseach, so just consider this as an aside:
My parents and their siblings all had a bunch of kids in the early 60’s, so we’re all hitting our 50’s now. I noticed about 10 years ago I started getting regular comments from my aunts and uncles (my parents died young – one of cancer, one of hearth diesease), who only see me a few times a year, that I look so young for my age. My uncle stares at me like I’m an alien, and asks me what I do to look so young. I’m a middle-aged gal, and I still get hit on by men (attractive ones) 15 or more years my junior. The only signficant lifestyle difference I know of between myself and my siblings and cousins is that I have been vegan or vegetarian most of my adult life. Just some food for thought.
If you’re on this page reading this thread, it’s because you or someone you care about has cancer and you’re looking for answers. I wish you all the best, and encourage you to learn more about a plant-based diet. If done correctly, you can get all (and I do mean all) the nutrients you need to be healthy from a plant-based diet. I’ve met people who actually came back from diagnoses of terminal cancer by changing their diet. Never met a one, or heard of one, who did the same by eating more meat and dairly products. Best wishes to everyone!
You’re dancing around the question. If you have the answer to the question, then answer it. Instead of all the text you typed above, you could have given me about five sentences on the putative mechanism by which meat causes cancer, and a few references which demonstrate this in living organisms. What you put above sounds more like a defense of intelligent design, and basically boils down to “it’s obvious because it’s obvious”. It’s only obvious to you because you “know” the truth.
Absolute belief is antithetical to science. Real science is always conditioned on evidence, and we must be open to changing our beliefs as new evidence comes to light. Personal experience: a few years ago, I would have claimed that the only good carb is a dead carb. But as new evidence came to light on the details of carbohydrate metabolism, the development of metabolic syndrome, and the vast differences between foods we tend to lump together as “carbs”, I’ve revised that position significantly. If you had some slam-dunk evidence showing that meat caused disease, I’d have to take that seriously. I’m not nearly so fond of hamburgers that I would trade my life for them, or even my current quality of life (which is vastly superior to what it was previously, including the time when I was vegetarian).
So suppose somebody came up with the slam dunk clinical trial showing that red meat not only did not cause cancer, but was potentially protective. Would you update your beliefs, or find some rationalization why this study can’t be true, “because some facts just speak for themselves”? “Facts” in science never speak for themselves, they are always conditioned on the current evidence and beliefs, and hence are never actually “facts” but rather “the thing we have the most belief in right now”.
I share your situation of being one of the more healthy people in my family, getting comments on how great I look, etc. Doctors and other “health professionals” get a little googly-eyed when I tell them how I eat, relatively how little exercise I do, etc. I have a strong suspicion if we compared diets, we would find more similarities than differences.
Oh, I forgot to mention: I am the only one of my age group within my family that has yet to experience arthritis, high blood pressure, high cholesterol – all that stuff that starts to creep up people in their fifties.
http://comprehensivefitness.blogspot.com/2011/08/effects-of-15-days-of-100-grams-of.html
Interested to hear your take on this. Science only, please, no conspiracy theories or “it’s obvious”.
The Pulitzer prize nominated book, “Diet for a New America,” by John Robbins is a great jumping off point for anyone unfamiliar with, and wishing to become familiar with, the long ago, and well-established, link between meat consumption and disease. (For some reason the focus recently is on heme iron, but the ways in which red meat does a number on the human body involves much more than that.) No conspiracy theories or lack of scientific evidence here. Just tons of research spanning decades that has been professionally presented over and over and over again by countless different and independent entities. Mr. Robbins book has been heralded as being one of, if not the most, comprehensive on this subject.
Here’s a handy link with a synopsis of the book as well as some informative excerpts:
http://michaelbluejay.com/veg/books/dietamerica.html
Wishing everyone a long and healthy life!
You still haven’t answered the original question. What are any of the “ways in which red meat does a number on the human body”?
Does this book also discuss the evidence which shows no connection between meat consumption and cancer? A common error in scientific inference is to assume that a study showing no effect does not update belief in a hypothesis (fancy way of saying people tend to ignore negative results, well established in studies of scientific publications).
Meat or wheat?
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC518895/?tool=pubmed
Wow, that’s a fascinating finding about breast cancer!!
But diagnosed celiacs presumably eliminate wheat from their diets…yet experience (slightly) higher malignancy and mortality rates. So, is eating wheat protecting the rest of us?
Diagnosed celiacs probably only eliminate wheat from their diets after being clinically diagnosed, which probably implies many years of living in the diseased state. According to Davis’ book Wheat Belly, people go for an average of something like 11 years between symptom onset and clinical diagnosis. And “symptom” onset presumably means the severe GI distress of celiac, as opposed to lower grade (and possibly non-GI) symptoms.
Anyway, your point is a good one. Obviously we need the studies that compare people who eat no wheat to those who do. Going to be tough to do within the same population, given the (rather ridiculous) ubiquity of wheat in the modern food supply.
would very much like to read the studies, reports, published articles that you base your opinions on.
also whether or not red meat has heme-iron, is just one single facet of the “red meat” controversy. unfortunately the way red meat is raised in this country leaves much to be desired.
if you dare read “Dying for a Hamburger”.
I wish you luck that you may never ever have to deal with the consequences of the Standard American Diet.
Just to throw a wrench into things, the immune system and inflammation are highly linked to some cancer types. Sorry, I just don’t have the time to put in links to articles right now. I have a test tomorrow. Celiac’s is an immune disorder, which may (or may not) imply that it can potentially have wide-ranging effects in the body, and may have little to do with whether people who do not have Celiac’s eat wheat and don’t get cancer. Talk about uncontrolled variables, an immune disorder will complicate everything every time!
I did witness the death of a 45 years old man, the second day after he consumed two pounds of meat and meat fat at night. He slept but did never wake up.
A lot of people cant accept the fact that consuming a lot of red meat could cause cancer and heart problems. They are bad ass type of human, which makes me laugh. Amazing article, but only smart people would get benefit from its content. Who cares about the rest since they want to live life to the “fullest”. All what they care about it their bellies.
I just read “Cut red meat intake and don’t eat ham, say cancer researchers” and the white elephant in the room is that in their view grass-fed all natural beef is equivalent to processed luncheon meat?!? Also, as has been pointed out here, there is no differentiation between beef as part of a balanced diet and someone who’s only vegetable is a white potato in the form of a french fry!