I have mixed emotions regarding Breast Cancer Awareness Month. On the one hand, I look forward to it because it provides us with a pretext to get out science-based messages about breast cancer and to highlight a lot of the cool science that we do at our cancer center. On the other hand, the quacks see an opportunity in Breast Cancer Awareness Month to spread their message too. That message, not surprisingly, generally involves attacking science-based modalities for the detection and treatment of breast cancer and promoting their “alternative” methods. For example, last year, Christiane Northrup promoted thermography as somehow being better than mammography for the early detection of breast cancer. It’s not. Yet there she is this year again, still promoting the same nonsense. In years past, I’ve seen people like Dennis Byrne promoting a link between abortion and breast cancer, a link that is not supported by science. I’ve seen the likes of Mike Adams claiming that Breast Cancer Awareness Month is nothing more than a conspiracy by the male-dominated “cancer industry” to keep women down and misinformation about “myths” of breast cancer while likening the “cancer industry” to Nazi extermination camp commanders and chemotherapy to Zyklon-B. I kid you not about that last part. Indeed, during October, I frequently get to look forward to images like this one (click for a larger image):

Or this one:

You get the idea.

This year, things have struck me as being unusually quiet on the Breast Cancer Awareness Month-related quackery front. That’s not to say that there hasn’t been anything. It’s just that it seems to have started later in the month (usually the Adamses of the world are chomping at the bit and start their barrage right around October 1) and been somewhat lacking in the sheer—shall we say?—looniness of past years. Sure, it’s possible that I haven’t been looking in the “right” (if you can call them that) places. There is still a week left in the month; I’ll try harder. In the meantime, leave it to Dr. Joe Mercola to provide me with a couple of examples.

For example, just yesterday Mercola dropped this blob of misinformation entitled The Cancer Time Bomb Sitting in Your Refrigerator – Will You Stop Consuming It? Its message can be boiled down to: “Recombinant bovine growth factor in milk causes breast cancer.” The article begins:

There is one food you may be surprised to learn, that is directly linked to breast cancer—and that is pasteurized dairy in the form of milk or milk products.

The risk lies in consuming milk from cows treated with a synthetic, genetically engineered growth hormone called rBGH, and unfortunately, this applies to about one third of the dairy cows in America.

When you consume dairy products from these cows, every product made from their milk is contaminated with this dangerous hormone—be it cheese, ice cream, yogurt, butter—or just plain milk.

Cows are injected with rBGH to boost their milk production.

To back up this contention, he included an interview with Dr. Shiv Chopra, a man who trained as a veterinarian in Punjab and then later emigrated to Canada, where he received a PhD in Microbiology from McGill University. Outside the quack world, he is known for a whistleblowing incident and claimed that he had been pressured to approve animal drugs of questionable safety. Since then, he appears to have drifted further and further into dubious medicine, including anti-vaccine views (Chopra has even said that “no flu vaccine has ever worked”) and crankery about genetically modified foods (GMOs). His bête noire appears to be—you guessed it—bovine growth hormone (rBGH), also called recombinant bovine somatotropin (rBST). Here is the interview:

BGH is a peptide hormone that is produced using recombinant DNA techniques. It is used by farmers to increase milk yield by cows, which it can do by as much as 10%, and it has been fairly controversial. According to Wikipedia, the U.S. is the only developed country that allows human consumption of milk from cows injected with rBGH. I’m not going to comment whether in general it is a good or a bad idea to be using rBGH to increase milk production or what other health effects on those who consume the milk might be. It’s generally agreed that rBGH is associated with a number of health problems in cows, including infertility, lameness, hoof disorders, and shortened lifespan, according to a review and meta-analysis in the Canadian Journal of Veterinary Research, although most of the relative risks are relatively small. It’s also known that rBGH is associated with an increase in clinical mastitis, but it is not clear whether this is a direct effect of the hormone or an indirect effect of increased milk production due to the hormone.

So what about breast cancer? Hold on for just a little bit longer. I’m getting to it. According to Mercola and Chopra:

IGF-1 is a potent hormone that acts on your pituitary gland to induce powerful metabolic and endocrine effects, including cell growth and replication. Elevated IGF-1 levels are associated with breast and other cancers. When cows are injected with rBGH, their levels of IGF-1 increase up to 20-fold, and this IGF-1 is excreted in the milk.

According to some confidential, unpublished industry studies, IGF-1 levels consistently elevate by 25 to 70 percent in rBGH milk. In reality, it is probably worse than that, since standard calculation techniques used by the dairy industry underestimate IGF-1 levels by a factor of four.

In one study, a six-fold increase in IGF-1 levels in milk were found as early as seven days following rBGH treatment.

IGF-1 stands for “insulin-like growth factor-1,” which is a peptide hormone that’s been much studied in relation to cancer. Indeed, if you search PubMed for “IGF-1 and breast cancer,” the search returns 1,375 references, in part because IGF-1 plays an important role in mammary development but, more importantly, because IGF-1 and the IGF system are promising targets for therapy in breast cancer; i.e., blocking IGF-1 signaling could well be an effective treatment. So how does this translate to the basic message of this article, which is a claim that milk from rBGH-treated cows causes breast cancer? This is how Mercola and Chopra make the link:

Only one of every 10 breast cancer cases is attributed to genetics—the other nine are triggered by environmental factors, some of which are dietary. The fact that increased IGF-1 levels in hormone-treated milk increase your risk for breast, colon, and prostate cancers as has been documented in about 50 scientific publications over the past three decades. Among them is the 1998 Harvard Nurses Health study, which showed that premenopausal women with elevated IGF-1 levels had up to a seven-fold increase in breast cancer. And women younger than age 35 who have elevated IGF-1 have more aggressive breast cancer.

The very first sentence of the paragraph above is full of so much wrong that it’s hard not to chuckle. The wrong is the assumption that because only one in ten breast cancer cases can be attributed to clearly defined genetic causes then that must mean that all of the rest must be triggered by environment. In a word: No. The genetics of breast cancer are complex and multifactorial, and many breast cancers are due to spontaneous mutations in key genes. With the exception of certain well-known genetic mutations, such as in BRCA1 or BRCA2, the division between “genetic” causes of breast cancer and other causes is not so clear cut. As for associations between elevated IGF-1 levels and cancer, they are just that: Associations. Correlations. The observation that elevated levels of IGF-1 appear to be correlated with some cancers does not mean that consuming IGF-1 causes cancer. After all, many cancer cells themselves make IGF-1. Indeed, a review from several years back concluded that “circulating concentrations of IGF-I and IGFBP-3 are associated with an increased risk of common cancers, but associations are modest and vary between sites.”

Here’s another hole in Chopra and Mercola’s “theory,” milk consumption from cows not treated with rBGH has been shown to increase IGF-1 levels, as a meta-analysis from two years ago found. Most of the studies evaluated in the meta-analysis were not from the U.S.; in fact one of them included children from Mongolia and the U.S. The authors point out that milk naturally contains IGF-1. Also remember that IGF-1 is a protein. In general, proteins are not well-absorbed; in general they are broken down to their constituent amino acids or to di- or tri-peptides, which is how they are absorbed by the intestinal tract. The authors also point out:

In addition to a direct effect of milk-borne IGF-I, the observed association may reflect increasing protein or total energy intake. Studies showed that protein-energy malnutrition decreased IGF-I levels. The IGF-I level was increased in response to improvements of both protein and energy intake during re-feeding (Crace et al. 1991; Zamboni et al. 1996). Indeed, of these cross-sectional studies we identified, eight studies reported that protein, especially animal protein intake, was positively correlated with circulating IGF-I levels (Giovannucci et al. 2003; Holmes et al. 2002; Hoppe et al. 2004a; Colangelo et al. 2005; Larsson et al. 2005; Rogers et al. 2006; McGreevy et al. 2007; Norat et al. 2007). Of note, one study indicated that milk consumption was no longer a significant predictor when protein was adjusted (Giovannucci et al. 2003). Thus, the possibility of protein intake as an intermediate of milk consumption and IGF-I level cannot be excluded. It is likely that milk, as an important resource of protein for humans, provides some specific essential amino acids that are the most important nutrient determinants of IGF-I (Takenaka et al. 2000). In addition to protein, calcium— another important nutrient in milk—was considered a component stimulating the IGF-I level (Rosen 2003). In five cross-sectional studies reporting that milk consumption was positively associated with IGF-I, calcium also showed a positive correlation with the IGF-I level (Ma et al. 2001; Holmes et al. 2002; Colangelo et al. 2005; Budek et al. 2007; Norat et al. 2007). Therefore, milk-borne IGF-I, protein and calcium in milk may be responsible for the increase of circulating IGF-I level in milk consumers.

In other words, whatever health problems might or might not be attributable to the consumption of milk from cows treated with rBGH, breast cancer is not one of them. There’s no evidence that the IGF-1 in milk is a major source of elevated IGF-1 in humans; indeed, it’s probably not even absorbed in sufficient amounts to make a difference. Any elevation of IGF-1 due to milk that has been reported appears to be due to the milk itself, or milk consumption is a marker for more protein consumption, which is the real cause of elevated IGF-1 levels in the serum. Finally, it’s not even clear whether IGF-1 is a biomarker that correlates with other risk factors associated with breast cancer or whether it is in any way causative. to put it bluntly, the quacks, as usual, have extrapolated far beyond what available data show. Indeed, in animal models, elevated rBGH doesn’t even correlate with mammary carcinogenesis.

Oh, no! Aluminum is deadly!

So, let’s see. If we are to believe Mercola, milk, particularly milk from cows who received the dreaded rBGH, is deadly and will give you breast cancer; that is, of course, unless it’s raw milk, which if you believe Mercola and his ilk is a nutritional panacea. But it turns out that milk isn’t the only deadly threat that will cause breast cancer on Planet Quack. Mercola asks: Are Aluminum-Containing Antiperspirants Contributing To Breast Cancer In Women? The answer: Almost certainly not, although Mercola tries his damnedest to dance around the evidence to demonstrate that it is a horrific risk factor for breast cancer. Specifically, it’s supposed to be the aluminum:

Research, including one study published this year in the Journal of Applied Toxicology, has shown that the aluminum is not only absorbed by your body, but is deposited in your breast tissue and even can be found in nipple aspirate fluid a fluid present in the breast duct tree that mirrors the microenvironment in your breast. Researchers determined that the mean level of aluminum in nipple aspirate fluid was significantly higher in breast cancer-affected women compared to healthy women, which may suggest a role for raised levels of aluminum as a biomarker for identification of women at higher risk of developing breast cancer.

The report discussed is a small pilot study of 35 patients, 16 with breast cancer and 19 with no cancer. While the results are somewhat provocative, it is important to remember that (1) the study is small and (2) the significance of the results are unknown. More importantly, there were a lot of confounding factors not controlled for. For example, presumably both women with breast cancer and those without in the study there was no serious attempt to control for confounding factors or to quantify the use of aluminum antiperspirants. Indeed, there are significant differences between the two groups. For example, the median age of the cancer group was 56, while it was 40 for the no cancer group. Perhaps something as simple as age could account for the difference. Does something happen after menopause leading to increased accumulation of aluminum from the natural exposure that we all have? Who knows? No analysis was done. Another possibility is that breast cancer might somehow accumulate aluminum more than normal tissue.

In other words, the study tells us absolutely nothing about whether or not aluminum-containing antiperspirants contribute to breast cancer risk.

Mercola’s next red herring is this:

In a 2007 study published in the Journal of Inorganic Biochemistry, researchers tested breast samples from 17 breast-cancer patients who had undergone mastectomies. The women who used antiperspirants had deposits of aluminum in their outer breast tissue. Concentrations of aluminum were higher in the tissue closest to the underarm than in the central breast.

Why is this a glaring red flag?

Aluminum is not normally found in the human body, so this study was a pretty clear sign that the metal was being absorbed from antiperspirant sprays and roll-ons. Please note that aluminum is typically only found in antiperspirants. If you are using a deodorant-only product it is unlikely to contain aluminum but might contain other chemicals that could be a concern.

Aluminum is not normally found in the human body? Did Mercola even read the previous article he cited? That article in and of itself demonstrated that aluminum is found in measurable quantities in normal human breast tissue nipple aspirates. Its finding was simply that it was found at higher levels in breasts with cancer. Come to think of it, did he even bother to read the study he just cited? It showed detectable levels of aluminum in normal breast tissue, too!

In any case, the claim that aluminum antiperspirants cause breast cancer is a classic case of confusing correlation with causation. The argument you will frequently see made is that most breast cancers occur in the upper outer quadrant of the breast. Because that quadrant of the breast is closest to the underarm, which is where antiperspirants are used, it must be the antiperspirants! And global warming is most definitely due to the decreasing number of pirates over the last three centuries. In fact, about half of all breast cancers develop in the upper outer quadrant of the breast, but it’s not because of antiperspirant use; it’s just because of a very simple thing. There is more breast tissue there than in other quadrants of the breast, and the number of breast cancers diagnosed there is proportional to the amount of breast tissue. Moreover, there is good evidence that there is no correlation between the use of antiperspirants and breast cancer. At the most, we can say that there might be such a link, but a fair assessment of the evidence suggests that such a link is unlikely.

And all the rest

Now that I’ve dealt with the two relatively serious claims regarding breast cancer and various environmental factors, let’s conclude by moving on to the fun stuff. also in the second article are some real howlers. For example:

In his 1975 article, Chinese Lessons For Modern Chiropractors, Dr. George Goodheart – known as “the father of Applied Kinesiology” — explained what he calls the “Antenna Effect.” Essentially, he discovered that by taping a small metal ball over an acupuncture point, you could achieve longer-term stimulation to that point in question. This discovery led to what are now known as AcuAids — small magnetic patches that are used by thousands of doctors across the world.

However, just like a small metal ball, any metal constantly applied to any given energy channel or point on your body can have the same stimulating effect. Over time, the continued stimulation can cause a subsequent decrease in function of important neuro-lymphatic reflex points located below your breasts.

In addition, the metal wire may act as an antenna attracting electromagnetic fields, which may also increase your risk of breast cancer. Fortunately, you can easily remove the piece of metal wire and replace it with a plastic rod of comparable size, which will provide the support but not simulate the antenna effect.

Yes, that’s right. Don’t wear those underwire bras, ladies. They concentrate electromagnetic radiation around the breasts. This is, of course, utterly ridiculous; the magnitude of such fields is minimal and the likelihood that they have any effect whatsoever on the risk of breast cancer even less. I would point out that advice from someone whose claim to fame is to be the “father of applied kinesiology,” a particularly silly form of quackery is likely to be as based in science as applied kinesiology is; i.e., not at all.

Much of the rest of the article includes typical misinformation about mammography, including exaggerated fears about the radiation. I’ve discussed such issues before many, many times before; so I refer you to various links. Suffice it to say: Mercola, as usual, doesn’t know what he’s talking about.

Breast Cancer Awareness Month is the proverbial two-edged sword. On the one hand, those of us in the field can take advantage of the event to highlight issues of breast cancer and breast health and try to call attention to new science and new discoveries about breast cancer. On the other hand, we have promoters of pseudoscience like Mike Adams and Joe Mercola to contend with. Given that there’s still a week left in the month, I have to wonder what, if anything, they’ll come up with next. Whatever it is, you can be sure it won’t be based on science.


Posted by David Gorski

Dr. Gorski's full information can be found here, along with information for patients. David H. Gorski, MD, PhD, FACS is a surgical oncologist at the Barbara Ann Karmanos Cancer Institute specializing in breast cancer surgery, where he also serves as the American College of Surgeons Committee on Cancer Liaison Physician as well as an Associate Professor of Surgery and member of the faculty of the Graduate Program in Cancer Biology at Wayne State University. If you are a potential patient and found this page through a Google search, please check out Dr. Gorski's biographical information, disclaimers regarding his writings, and notice to patients here.