T Nation

Link Between Casein and Tumors/Cancer?


#1

I thought this was interesting and somewhat alarming:

http://cancerres.aacrjournals.org/content/43/5/2150.short


#2

Look up Joe Jackson’s song “Cancer”


#3

I’d like to hopefully see a T-Nation article on this…either supporting or debunking it.

Especially since we’re talking about casein, which is something I consume large amounts of via Metabolic Drive.


#4

The study examines administration to rats simultaneously of aflatoxin in large amounts and casein. Results could be different when not consuming aflatoxin.

The study doesn’t compare different types of protein, so it says nothing about casein specifically relative to other proteins. It might be that rats are more sensitive to aflatoxin on any high protein diet.

The study did nothing to determine mechanism of the difference in toxicity of aflatoxin according to the different diets. So it gives nothing with which even to speculate how the finding might relate to other questions, such as diets without significant aflatoxin, or diets with aflatoxin but a species differing from the rat.

And though it’s a 1983 study, which has given plenty of time since, its impact was so low that it’s never been cited since by any other study. This makes it unlikely that the results have been replicated or that any further results have built on this, and also means that other workers at least with regard to their own published studies didn’t find any citable importance to this work. That doesn’t change potential validity if valid in the first place that rats are less poisoned by aflatoxin on a low rather than high protein diet, but lack of followup after so much time suggests less meaning than if there were further supporting results.


#5

[quote]Bill Roberts wrote:

  1. The study examines administration to rats simultaneously of aflatoxin in large amounts and casein. Results could be different when not consuming aflatoxin.[/quote]

MAJOR EDIT:
Actually, this has been clarified to me…So the researchers gave all of the rats in the study aflatoxin-induced tumors, but some of the rats were fed a diet of 5% casein and others were fed 20% casein. The rats that were fed 20% casein exhibited a 6-fold increase in the size of the tumor compared to the mice on the 5% diet. What was also interesting was that when they switched the amount of protein, i.e. 20% to 5% and vice versa, tumor growth actually reversed. Thus, if was found that casein, the main protein in milk, was a significant factor in tumorigenesis. The fact that they were actually able to REVERSE the growth of cancer on a low protein diet is pretty astounding.

I need to do more research now…

EDIT:

How would you respond to this?

[quote]Cancer

The authors link breast cancer to the long-term exposure to higher concentrations of female hormones, which in turn is associated with early menarche (age at first menstruation), late menopause, and a high concentration of blood cholesterol. They argue that all these risk factors are linked to a diet high in animal protein, particularly casein from cow milk. The average Chinese woman is exposed to 35�?�¢??40 percent of the lifetime estrogen exposure of the average British or American woman, and the rate of breast cancer among Chinese women is about one-fifth of the rate among Western women.[27] They also argue that lower rates of colorectal cancer are associated with the consumption of plants high in dietary fiber, such as beans, leafy vegetables and whole grains.[19] This is supported by independent research. [28] [/quote]

The above is excerpted from this:


#6

see my edits above.

Also…another study (far more current…last year actually):


#7

Well, I have not read the book.

I immediately find that the authors strike me as persons who come to strong conclusions without needing sufficient evidence or even in the face of evidence. An example statement showing this would be “eating foods that contain any cholesterol above 0 mg is unhealthy.”

Given that sort of carelessness or ideologically-driven blindness (as a guess as to possible cause for such a statement) personally their conclusions and assertions will mean nothing to me, but what of the references they may cite and the facts behind them?

The one relevant to protein seems to be this: http://web.archive.org/web/20090223222003/http://www.nutrition.cornell.edu/ChinaProject/

I hope that ActivitiesGuy may contribute here, as the question is whether statistics of this sort are good at picking out causes or not, a main reason not being that confounders are likely to exist which are not being accounted for.

In this instance, just speaking about human beings it’s unlikely that all behaviors and situations of persons who have a substantial difference in behavior, such as eating a lot of meat versus not doing so, will be the same.

Very likely, other things go along with this difference. Perhaps those who do not each much meat have less money, and this being China, perhaps enough less money that some degree of caloric restriction is associated. Perhaps those who eat much meat are, for reasons other than meat causing fatness, fatter. Perhaps those eating much meat eat less of some healthful things, and the real issue is absence or reduced intake of the other things, not presence of the meat.

As personal opinion, these kinds of studies are terrible for even suggesting causation.

On the xenoestrogen issue, this is supported but I know of no evidence that meat is a significant cause.


#8

This is an in vitro study (test tube, Petri dish.) Casein doesn’t enter the bloodstream intact and therefore reach prostate cells as casein.

On the aflatoxin one, yes, high protein (not specifically casein, as there was no comparison with any other protein) was worse for rats already having the aflatoxin lesions. I’m at a loss as to why this should be of concern when not having aflatoxin lesions.


#9

[quote]Bill Roberts wrote:
Well, I have not read the book.

I immediately find that the authors strike me as persons who come to strong conclusions without needing sufficient evidence or even in the face of evidence. An example statement showing this would be “eating foods that contain any cholesterol above 0 mg is unhealthy.”

Given that sort of carelessness or ideologically-driven blindness (as a guess as to possible cause for such a statement) personally their conclusions and assertions will mean nothing to me, but what of the references they may cite and the facts behind them?

The one relevant to protein seems to be this: http://web.archive.org/web/20090223222003/http://www.nutrition.cornell.edu/ChinaProject/

I hope that ActivitiesGuy may contribute here, as the question is whether statistics of this sort are good at picking out causes or not, a main reason not being that confounders are likely to exist which are not being accounted for.

In this instance, just speaking about human beings it’s unlikely that all behaviors and situations of persons who have a substantial difference in behavior, such as eating a lot of meat versus not doing so, will be the same.

Very likely, other things go along with this difference. Perhaps those who do not each much meat have less money, and this being China, perhaps enough less money that some degree of caloric restriction is associated. Perhaps those who eat much meat are, for reasons other than meat causing fatness, fatter. Perhaps those eating much meat eat less of some healthful things, and the real issue is absence or reduced intake of the other things, not presence of the meat.

As personal opinion, these kinds of studies are terrible for even suggesting causation.

On the xenoestrogen issue, this is supported but I know of no evidence that meat is a significant cause.[/quote]

valid points.

I think the potentially key takeaway is that…the thing with cancer is that there isn’t one single pathway through which cancer happens. In fact, given my family’s history, there’s a good chance that I have cancer cells in my body right now. The growth of these cancer cells depend on activation by a number of factors, like environmental factors. The study showed that Casein is one of those activators. Now that doesn’t mean because one drinks milk or casein via protein shakes that that person will definitely get cancer of course …but it significantly increases chances it appears.


#10

The prostate cell study where the cells were directly exposed to intact casein really doesn’t show that, because no intact casein gets into your bloodstream.

The aflatoxin study really didn’t show that either, because there’s really no basis to conclude that what happens with aflatoxin lesions happens in general with cancer.


#11

I don’t know if I can post these links but Campbell’s study has gotten quite some critique here:

(If I can’t link try googling Weston price and china study)(edit: try Weston price, the curious case of Campbell’s rats)

and by Denise Minger on her blog (probably can’t link to that, Weston price links to her as well)

Very extensive critiques, so you’ve got some reading to do, see what you think.


#12

I think Bill’s intuition was spot on when he referred to “ideologically-driven blindness”.

Time for my shake.


#13

[quote]grippit wrote:
I don’t know if I can post these links but Campbell’s study has gotten quite some critique here:

(If I can’t link try googling Weston price and china study)(edit: try Weston price, the curious case of Campbell’s rats)

and by Denise Minger on her blog (probably can’t link to that, Weston price links to her as well)

Very extensive critiques, so you’ve got some reading to do, see what you think.[/quote]

Thanks for the heads up. Must look into this.

Are the critiques with specific regard to casein? Some of the studies I’ve linked are not at all related to Campbell’s work yet come to similar conclusions.


#14

It seems to me that the general absence of material on this one (allegation of carcinogenicity of casein) is overwhelming.

Even aside from scientists and doctors, wouldn’t just everyone who wants to be heard find this a spectacular subject if there were basis for it? How could the talking-heads on TV, for example, possibly pass this one by if it met even their standards? “Does milk give your kids cancer? Tune in at 11:00!”

And to say the least, scientists would be all over this too, for grant money if nothing else. They’d need something to go on though. Something.

But it’s the sound of crickets. And justifiably so, because to say the least there’s no smoking gun. There’s no proposed mechanism that I’ve seen, let alone a demonstrated one. There’s not even any correlative study it seems.

I’ve never seen anything to support the idea – including the above two studies.


#15

[quote]RDeschain wrote:

MAJOR EDIT:
Actually, this has been clarified to me…So the researchers gave all of the rats in the study aflatoxin-induced tumors, but some of the rats were fed a diet of 5% casein and others were fed 20% casein. The rats that were fed 20% casein exhibited a 6-fold increase in the size of the tumor compared to the mice on the 5% diet. What was also interesting was that when they switched the amount of protein, i.e. 20% to 5% and vice versa, tumor growth actually reversed. Thus, if was found that casein, the main protein in milk, was a significant factor in tumorigenesis. The fact that they were actually able to REVERSE the growth of cancer on a low protein diet is pretty astounding.

[/quote]

Not tumorigenesis. Tumor growth. Once you have tumors, pretty much any anabolic agent I can think of promotes their GROWTH. Insulin for example promotes the growth of existing tumors. Carbs. Testosterone. HGH. If you are trying to cause an anabolic effect you are going to typically use something that would make tumors (and everything) grow if you already have tumors.


#16

Bill, thanks for the additional points to consider and as always I really appreciate your input!

[quote]mertdawg wrote:

[quote]RDeschain wrote:

MAJOR EDIT:
Actually, this has been clarified to me…So the researchers gave all of the rats in the study aflatoxin-induced tumors, but some of the rats were fed a diet of 5% casein and others were fed 20% casein. The rats that were fed 20% casein exhibited a 6-fold increase in the size of the tumor compared to the mice on the 5% diet. What was also interesting was that when they switched the amount of protein, i.e. 20% to 5% and vice versa, tumor growth actually reversed. Thus, if was found that casein, the main protein in milk, was a significant factor in tumorigenesis. The fact that they were actually able to REVERSE the growth of cancer on a low protein diet is pretty astounding.

[/quote]

Not tumorigenesis. Tumor growth. Once you have tumors, pretty much any anabolic agent I can think of promotes their GROWTH. Insulin for example promotes the growth of existing tumors. Carbs. Testosterone. HGH. If you are trying to cause an anabolic effect you are going to typically use something that would make tumors (and everything) grow if you already have tumors. [/quote]

Interesting


#17

(So before you read, apparently casien may lead to cancer in rats because they lived long enough not to die from acute high aflatoxin doses. Casien apparently prevents tumors at all but extreme exposure carcinogens. Read on)

The China Study relayed Campbell?s findings with powerful simplicity. In a series of experiments, Campbell and his team exposed rats to very high levels of aflatoxin?a carcinogen produced by mold that grows on peanuts and corn?and then fed them a diet containing varying levels of the milk protein casein. In study after study, the rats eating only 5 percent of their total calories as casein remained tumor-free, while the rats eating 20 percent of their calories as casein developed abnormal growths that marked the beginning of liver cancer. As Campbell described, he could control cancer in those rodents ?like flipping a light switch on and off,? simply by altering the amount of casein they consumed.4

Despite these provocative findings, Campbell wasn?t ready to declare all protein a threat to public health and stamp the peanut butter aisle with Mr. Yuk stickers. Animal protein, it turned out, seemed to be uniquely villainous. In several of his experiments, when the aflatoxin-exposed rats were fed wheat protein or soy protein in place of casein, they didn?t develop any cancer?even at the 20 percent level that proved so detrimental with casein.5 It seemed that those plant proteins were not only PETA-approved, but also the least likely to turn rat livers into tumor factories.

These findings led Campbell to his firm and famous conclusion: that all animal protein?but not plant protein?could uniquely promote cancer growth. Out with the steak, in with the tofu! But as several critics have pointed out,6,7 that proclamation required a few somersaults of logic (and maybe some cartwheels of delusion). The effects of casein?particularly isolated casein, separated from other components of dairy that often work synergistically?can?t be generalized to all forms of milk protein, much less all forms of animal protein. An impressive number of studies shows that the other major milk protein, whey, consistently suppresses tumor growth rather than promoting it, likely due to its ability to raise glutathione levels.8,9 Another of Campbell?s own studies suggests that fish protein acts as a cancer-promoter when paired with corn oil, but not when paired with fish oil?highlighting the importance of dietary context (and the neverending terribleness of vegetable oils).10

And the kicker: one of Campbell?s most relevant experiments?which sadly received no mention in The China Study?showed that when wheat gluten is supplemented with lysine to make a complete protein, it behaves exactly like casein to promote tumor growth.11 This means that animal protein doesn?t have some mystical ability to spur cancer by mere virtue of its origin in a sentient creature?just that a full spectrum of amino acids provide the right building blocks for growth, whether it be of malignant cells or healthy ones. And as any vegan who?s been asked ?Where do you get your protein?? for the eight hundredth time will answer, even a plant-only diet supplies complete protein through various mixtures of legumes, grains, nuts, vegetables, and other approved vegan fare. Theoretically, a meal of rice and beans would provide the same so-called cancer-promoting amino acids that animal protein does. Indeed, Campbell?s experiments lose their relevance in the context of a normal, real-world diet opposed to the purified menu of casein, sugar, and corn oil his rats received.

But that?s only the tip of the proteinaceous iceberg. In his September 2010 article, ?The Curious Case of Campbell?s Rats,?12 Chris Masterjohn ventured beyond the well lit pages of The China Study to explore the dark alleys of Campbell?s publications firsthand. And what he found regarding the low-protein rats was a far cry from the sunshine-and-lollipops descriptions we read in the book. Although rats consuming a high-casein diet were indeed developing liver cancer as Campbell described, the ones in the low-casein groups?which were portrayed as downright bright-eyed and shiny-coated in The China Study?were suffering an even worse fate. Campbell?s research actually showed that a low-protein diet increases the acute toxicity of aflatoxin, resulting in cell genocide and premature death. Because protein deficiency prevents the liver from successfully doing its detoxifying duties, less aflatoxin gets converted into cancer-causing metabolites, but the end result is massive (and eventually deadly) tissue damage.

Even the research from India that jump-started Campbell?s interest in the diet-cancer link showed that rats on a low-casein diet were dying with disturbing frequency, while the high-protein rats?tumored as they may have been?were at least staying alive.13 (It?s surprising, then, that The China Study promotes a plant-based diet to prevent cancer, when death is equally effective and requires fewer shopping trips.)

More clues for understanding the casein-cancer research come from another Indian study?this one published in the late 1980s, and examining the effects of protein in aflatoxin-exposed monkeys instead of rats.14 As with Campbell?s experiments, the monkeys were fed diets containing either 5 percent or 20 percent casein, but with one important difference: instead of being slammed with an astronomically (and unrealistically) high dose of aflatoxin, the monkeys were exposed to lower, daily doses?mimicking a real-world situation where aflatoxin is consumed frequently in small amounts from contaminated foods. In a fabulous case of scientific switcheroo, this study showed that it was the low-protein monkeys who got cancer, while the high-protein monkeys rejoiced in their tumorlessness.

This apparent paradox highlights a major problem in Campbell?s rat research: the level of aflatoxin exposure plays a critical role in how protein affects cancer growth. When the aflatoxin dose is sky high, animals eating a low-protein diet don?t get cancer because their cells are too busy dying en masse, while animals eating a higher protein diet are still consuming enough dietary building blocks for the growth of cells?whether healthy or cancerous. When the aflatoxin dose is more moderate, animals eating a low-protein diet develop cancer while their higher-protein counterparts remain in mighty fine health.

In a nutshell, the animal protein fear-mongering in The China Study stems from wildly misconstrued science. What Campbell?s rat experiments really showed wasn?t that animal protein is a vengeful macronutrient of doom, but the following:

  1. High-quality protein promotes cell growth no matter where it comes from;

  2. Protein deficiency thwarts the liver?s ability to detoxify dangerous substances; and

  3. With more realistic doses of aflatoxin, protein is actually tremendously protective against cancer, while protein-restricted diets prove harmful.

http://www.westonaprice.org/health-topics/abcs-of-nutrition/the-china-study-myth/


#18

[quote]mertdawg wrote:

The effects of casein?particularly isolated casein, separated from other components of dairy that often work synergistically?can?t be generalized to all forms of milk protein, much less all forms of animal protein.

An impressive number of studies shows that the other major milk protein, whey, consistently suppresses tumor growth rather than promoting it, likely due to its ability to raise glutathione levels.8,[/quote]

Thanks so much for your post. Very compelling stuff. What you posted which counters Campbells’ study STILL seems to confirm that Casein is an activator. NOT that casein causes cancer but that casein can activate existing cancer cells. But you CAN"T extrapolate the findings of casein alone to other major milk proteins…such as whey, which has been found to consistently suppress tumor growth.

Therefore, it leads me to conclude that since MD Drive is a blend and not ONLY casein, there is a …balance so to speak.

And further, perhaps, Whey is safer for those with a lot of cancer in their family.


#19

I’m not sure what you precisely mean by casein being an “activator”, but it’s not a conclusion I would draw after reading the articles.


#20

In summary, if you already have tumors, might want to avoid isolated casein. But then again, if you already have tumors, you will be making a lot of life and dietary changes to go with that.