I came across an article in the HuffPo a couple days ago by Kathy Freston whose headline rather blatantly claimed that eating vegetarian diet is in fact a cure for cancer. Now you may respond by pointing out that whoever penned the headline used a question mark which may indicate that the website is not making a direct assertion. However, upon reading the article, I am forced to conclude that this is a mere act of keeping up appearances. The article is completely credulous and goes so far as offering recipes.
So why am I up set by this? There are two reasons. First, I feel, along with many other folks on the interwebs (see blog links), that it is important to the collective well being of society for crap science reporting to be called out and dissected in public and as loud as possible. Second, it plain dangerously irresponsible of the HuffPo, and frankly Dr. Campbell as well, to come right up to the brink of recommending to a massive reader base to forgo proven treatments for a bunch of nonsense. I have yet to address such articles, quite frankly, because I have let this blog lay fallow for quite some time. I have been busy trying to keep my head above water in my studies and have since all but abandoned the site till now. This article has woken me back up. I don’t pretend to claim that my response will cause any change by itself. To tell you the truth I don’t claim that any impressive number of folks will even read it. But I feel that it is important for me to at least add one more opportunity for some hapless internet mariner searching for more info on a subject to run into this side of the story.
I am sorry that this one is a bit long…
Ok lets dive in!
The skinny is that the article claims through an interview with T. Colin Campbell that by eating only “plant proteins” one can slow and even reverse the progression of cancer. Actually, he pretty much claims outright that it curse cancer. And not just “a” cancer, pretty much all cancers. This is a MAJOR warning sign, as cancers are as varied in their causes and therefore rational treatments as a field of wild flowers. It should give one pause to hear someone claim that they have the ONE thing that renders the entire class of problems solved. Throughout this post I will try to point out some of the hallmarks of peddling BS that are used, and you should look out for similar techniques when you read… well, pretty much anything. ESPECIALLY, if it happens to be on the internet. Ok, back to work. He tries to set up the idea that there is a fundamental difference in proteins originating from plants with respect to animals. From here, he claims that the difference has biological importance to cancer and that plant proteins:
the nutrients from animal based foods, especially the protein, promote the development of the cancer whereas the nutrients from plant-based foods, especially the antioxidants, reverse the promotion stage. This is a very promising observation because cancer proceeds forward or backward as a function of the balance of promoting and anti-promoting factors found in the diet, thus consuming anti-promoting plant-based foods tend to keep the cancer from going forward, perhaps even reversing the promotion. The difference between individuals is almost entirely related to their diet and lifestyle practices.
Remember that last part that I underlined there. We’ll come back to that. In short we are promised that through his
experimental study designs, epidemiological evidence, along with observation of real life conditions which had rational biological explanation, Dr. Campbell has made a direct and powerful correlation between cancer (and other diseases and illnesses) and animal protein.
Note the use of “real life conditions” as a church clothed version of anecdotes. The use of anecdotes is also not a good sign that a solid scientific argument is about to follow.
Now, to me as a molecular biologist all this sounds kinda fishy. All proteins otherwise known as polypeptides are made up of the same 20 fundamental amino acids (AAs). Also, the majority of original sequence structure of the proteins, the order in which the AAs are arranged, is destroyed by proteolytic (protein cutting) enzymes in your digestive system. So to the body, digested protein pretty much looks like a list of AA frequencies found in the last meal of the individual, ie 12% glycine 33% alanine etc (numbers cooked up for illustration’s purpose). And at this level there ARE some differences between plants and animals. You ever heard of those essential amino acids? That’s why you have to eat rice AND beans to get a complete set of the 20 AAs. There are about 9 AAs that are either found in one veggie or another but almost never all in one, so you need to combine certain veggies to ensure that you are getting enough of all 20. So I am wondering if he is gonna go down that counter-intuitive road with why the plants are actually BETTER, but we have to wade through a bit more before we finally get something of an answer to how he claims plant proteins are different.
He explains what happens during the onset and progression of cancer and for the MOST part makes sense out of it. He give three stages of cancer: Initiation (genes in certain cells get damaged), Promotion (cells with damaged genes proliferate), Progression (basically metastasis: invasion of other tissue by the cancer). But, he includes a point that seems to contradict itself and truthfully makes no real sense to me.
Although the initiated cells are not considered to be reversible, the cells growing through the promotion stage are usually considered to be reversible, a very exciting concept.
This makes NO sense, unless I am interpreting it wrong. The cancerous or pre-cancerous cells that are growing through the “promotion” phase are directly derived from the damaged cell in the initiation phase that he says can not be reversed. In fact the genes that get damaged to cause cancer are generally those functioning to protect against further damage. So, in general, its MUCH more likely that more will go wrong. How can copies of a cell that, according to him, is irreversibly cancerized now be reversible?
He goes on:
Although all cancer and other diseases begin with genes, this is not the reason whether or not the disease actually appears. If people do the right thing during the promotion stage, perhaps even during the progression stage, cancer will not appear and if it does, might even be resolved. … Consuming plant based foods offers the best hope of avoiding cancer, perhaps even reversing cancer once it is diagnosed. Believing that cancer is attributed to genes is a fatalistic idea but believing that cancer can be controlled by nutrition is a far more hopeful idea.
Note the choice to use the morally loaded language of “do the right thing” when talking about your response to your diagnosis of cancer. He wishes to associate his option with a more emotional response. He is not arguing in the language of reason. He proclaims straight-faced that being a vegetarian is the BEST HOPE for avoiding cancer (file this with what I told you to remember earlier about the lifestyle choice from the first quote). And finally we come to an argument that has absolutely NO place in a rationally derived persuasive argument. That last line is what is called an argument from final consequence. Basically, “my alternative is less depressing, therefore it must be right.” Umm… Nope. Thanks for playing. These types of arguments are relied on to make an audience “WANT” your side to be right, not to convince them that it actually is.
We have many more signs of quackery in here as well. For instance, when Ms Freston FINALLY gets around to asking him “What exactly is so bad about animal protein?” he responds thusly:
I don’t choose the word “exactly” because it suggests something very specific. Rather, casein causes a broad spectrum of adverse effects.
So, instead of giving us the promised “direct and powerful correlation between cancer (and other diseases and illnesses) and animal protein,” he waves his hands and says that he doesn’t want to give specifics, but that there are many mostly un-named effects. Once again this is another sign of the quack. Naming specifics opens you up to someone proving you wrong. Among the “broad spectrum” of effects that MAY or MAY NOT cause the cancer problems, he does name one claim that it acidifies the blood. At this point, I am having to keep reminding myself that this guy is a PhD in life sciences. This, by the way, is a lesson in itself; fancy letters after one’s name should not place them on that lofty infallible pedestal that priests and oracles enjoy. Of course I don’t believe that they should get a pedestal either, but that might be a different type of blog. The point is, always demand a cogent argument over spiffy credentials. Regarding the blood, its pH is very strictly regulated by opposing chemical forces in it called buffers.
Pretty much all water based solutions exist in some balance between acidity and basicity (aka alkalinity). The basic idea behind buffers is that they sort of lock in that balance at a certain pH. There are chemicals present in the solution that tend to “mop up” free hydrogen ions (these are what make a solution acidic) they by moving the balance more toward alkalinity. Likewise, a good buffer may have chemicals in it that mop up hydroxide ions (cause solution to be basic) thereby moving the balance more toward acidity. The effect is like a car’s shocks; or for you physics geeks, like a weight suspended between two opposing springs. You can move the weight to one side briefly, but the balanced forces exerted by the opposing springs will swiftly replace the weight to its original position. So it is in our blood. If your blood starts to get more acidic, it is automatically counteracted. Here is an article addressing some crap-based claims that involve blood-acidification. PLEASE read it. This claim seems to get so much play it would make Kobe jealous. Please read it and do your part in combating that one.
We have NOT been given a SHRED of confirmable information in spite of all that Dr. Campbell is claimed to have at his disposal. I don’t think we have been given any reason to believe that animal proteins are noticeably different as detectable by the body after digestion assuming that the vegetarian has chosen suitably balanced plants with regard to the essential amino acids. His basic claim here is that eating plants instead of meat cures cancer. Ms Freston asks “This is sounding like it’s a cure for cancer; is that the case?” He responds with:
Yes. The problem in this area of medicine is that traditional doctors are so focused on the use of targeted therapies (chemo, surgery, radiation) that they refuse to even acknowledge the use of therapies like nutrition and are loathe to even want to do proper research in this area. So, in spite of the considerable evidence–theoretical and practical–to support a beneficial nutritional effect, every effort will be made to discredit it. It’s a self-serving motive.
And with that he actually adds a claim of conspiracy against his idea to our list of quack qualities. Lets think critically a second about his core claim. He claims in the article that casein (milk protein) is “the most relevant cancer promoter ever discovered.” The emphasis was granted in the article mind you, not by me. So he claims milk is the best cancer promoter ever discovered. By the way his lab’s work ONLY looked at casein protein dosages and only in a liver cancer model in rats. Ironicly, that liver cancer model also seems to focus heavily on the interaction of a molecule, produced by some fungi, called aflatoxin to induce genetic mutations that lead to liver cancer. Where might one happen to encounter this potent liver carcinogen outside of a lab? Turns out the fungus grows on improperly handled food plants. Anyway, he then extrapolates to all animal protein and that the effect is the same in non-laboratory contrived situations and humans with out as far as I can tell any data driven reason. My guess is that he would point to the “real world” anecdotes mentioned above as his human data. However, as the adage goes: the plural of anecdote is anecdotes, not data. As far as his studies are concerned, I admit that I only hat time to briefly looked at a few (referenced below) and could not see that he actually ever tested plant proteins specifically as a control. His controls seem to be “normal rat chow” and he tests increasing dosages of casein against that. So he again, seems to have made a leap that, in my opinion, the papers that I looked at of his can not claim to support; plant protein not only promotes cancer less but REVERSES it. Where did that claim come from?! We can do some extrapolating of our own based on these claims. And I think that we would be more grounded in our doing so than he seems to be in many cases. Lets form some hypotheses. If his claims are true, then what ELSE must necessarily be true that we might be able to observe?
- If milk protein is in fact “the most relevant cancer promoter ever discovered,” then we should observe that cancer outcomes for people with lactose intolerance or in countries where milk is consumed less should be drastically better, not even just statistically significantly better by a few percent.
- If his claims (listed below) are true, then we should expect to observe that cancer should again be drastically reduced, to the point of almost entirely absent, in populations that only eat plants.
- “If people do the right thing during the promotion stage, perhaps even during the progression stage, cancer will not appear…”
- “Consuming plant based foods offers the best hope of avoiding cancer, perhaps even reversing cancer once it is diagnosed.”
- “The difference between individuals is almost entirely related to their diet and lifestyle practices.”
Now, you may think that I am over reaching with the magnitude of my expectations, but go back and read his claims, even the just the ones I outlined in the hypotheses. I think that you will find my expectations in the same ballpark as his claims. Right away, when put into this format, something looks fishy, but to say something solid one must actually have data. In the first hypotheses, I am afraid that I expect the published work in that area to be scarce. However, I did do a brief search and found a few studies regarding cancer and vegetarianism. Again, due to time constraints, I was only able to really look at one and drawing sweeping conclusions from one study is not optimal.
Here are the basics:
Objective : To investigate the health consequences of a vegetarian diet by examining the 12 year mortality of non-meat eaters and meat eating controls.
Subjects : 6115 non-meat eaters identified through the Vegetarian Society of the United Kingdom and the news media (mean (SD) age 38.7 (16.8) years) and 5015 controls who were meat eaters (39.3 (15.4) years).
The main outcome measured was death due to cancer and other causes. At first glance the data looks like it favors Campbell with the non-meat eaters doing a bit better. However, when confounding factors were accounted for such as smoking, body mass index, and socioeconomic status, the results were not as convincing. The conclusions drawn from the study were, in the words of the authors:
The reduced mortality from cancer among those not eating meat is not explained by lifestyle related risk factors, which have a low prevalence among vegetarians. No firm conclusion can be made about deaths from ischaemic heart disease. These data do not justify advice to exclude meat from the diet since there are several attributes of a vegetarian diet apart from not eating meat which might reduce the risk.
I will say that as I briefly looked at few others and that in some cases the result seems to favor the veggie-heads a bit and in others not. In one case, over all cancer seemed reduced (NOT eliminated as we would expect from Campbell’s claims) but for a particular type the risk was increased for the non-meat eaters. Remember his claims that his results are not cancer specific. Also remember this:
The problem in this area of medicine is that traditional doctors are so focused on the use of targeted therapies (chemo, surgery, radiation) that they refuse to even acknowledge the use of therapies like nutrition and are loathe to even want to do proper research in this area. So, in spite of the considerable evidence–theoretical and practical–to support a beneficial nutritional effect, every effort will be made to discredit it.
No one will even consider the idea that plant diets might improve cancer hunh? No supported research hunh? I suppose that if confronted with the results of this very appropriate line of research, he would amend his statement to include something like “the data was cooked up to prop up their buddies in ‘big pharma.'”
To conclude, this is another in a pretty long string of article devoted to non-reality supported health information by the HuffPo in particular. Why do I care? Well particularly, with a media outlet the size of the HuffPo the audience of people reading it with only a high school education in biology (or scientific thinking in general) along with a family member or friend suffering from cancer is likely to be substantial. Even at the late date of this posting, a google search for “cure for cancer” turns up Ms Freston’s post as number three.
If the message was simply that you should “eat well and be active,” I would have no problem. But this guy and many like them are not saying that although it may look like that from a distance. He is advocating his methods apart from medical treatment. He claims over and over, that his method is the BEST HOPE. That his method is basically all you need. It is not overstating anything to conclude that a non-negligible number of people WILL choose this over proven medical standards of care. And will die as a direct result. Thats why I care, and why this reckless irresponsibility masquerading as science and health reporting makes me furious. If you want some example please top by whatstheharm.net for some real examples of the inescapable results.
Some of Campbell’s publications: