This morning someone flicked an article about the connection between antiperspirants and breast cancer onto my Facebook page, along with this illustration.
I stopped using antiperspirants some years ago (except for those occasional social events where sweaty armpits would be likely, and definitely not considered a social asset), after my mother’s lymph nodes were removed as part of her breast cancer treatment. It just didn’t seem to me a natural, sensible thing to go clogging up the pores that Mother Nature so carefully provided for my body. So my natural response to this little Facebook post was to click the thumbs up and hit “share”. And then I thought this would be a good topic for a post here.
Now, I don’t post stuff on this blog—unless it’s about personal experience--without doing a bit of research on the subject first. That’s my science training coming to the forefront. So I set out to discover (as much as one can in a couple of hours): Can antiperspirants cause breast cancer? And this is what I found out.
The short answer is: we don’t have any proof that antiperspirants cause breast cancer. But, on the other hand, we don’t have any proof that they don’t either. The truth is, there isn’t enough research into this question to give us a definitive answer. Here’s what we DO know:
The lymph nodes located in the tender area under the arms are connected to the breast tissue, and in the case of breast cancer are often surgically removed along with breast tissue. Lymph nodes, which as you can see in the diagram on the left, occur all over the body and operate as part of the body’s immune system, filtering, trapping, and destroying bacteria, viruses, and other pathogens, including cancers. Cleansed fluid from the lymph nodes is then released into the blood stream. But the lymph glands are not sweat glands, they are not directly linked to the skin surface, and they probably are not directly affected by antiperspirants. Sweat glands, on the other hand, are.
Most antiperspirants contain aluminium, which blocks the body’s sweat glands where it is applied. Sweat is a salty liquid excreted by the eccrine glands in response to stress (which can be physical, like exercise or heat, or psychological). It has little or no odour[i], but develops a smell with the presence of bacteria, or sexual pheromones[ii].
Blocked sweat glands do not cease producing sweat, they simply are unable to expel that fluid to the skin’s surface—as they are designed to do--because the duct has been blocked. Besides causing the disruption of a natural bodily process, the aluminium in antiperspirants is a concern for another reason.
Aluminium is a toxic metal that has been linked to cancers, including breast cancer[iii]. One recent study shows changes in human mammary cells indicative of tumour and pre-tumour stages caused by exposure to aluminium chloride[iv], and another recent study showed elevated levels of aluminium in the nipple duct fluid of breast cancer patients compared with that extracted from healthy women[v]. Earlier studies noted the disproportionate number of breast tumours occurring in the upper outer quadrant of the breast, closest to the underarm area where antiperspirants are applied, and where the concentration of aluminium is highest[vi]. None of this research is adequate for “proof” that the aluminium in antiperspirants causes breast cancer, but there does appear to be a correlation. And obviously, breast cancer can be caused by other things as well.
Among those “other things” are parabens, a group of man-made preservatives commonly used in antiperspirants, deodorants, shampoos, and other skin and body products. Parabens can mimic estrogens in the body. Although the female body naturally produces estrogens during the reproductive years, high life-time levels of estrogens are correlated with an increased of risk of breast cancer[vii]. In one recent study where they collected and examined malignant breast tissue following mastectomies, 99% of the samples revealed the presence of parabens[viii]. Not all of the women in that study had used antiperspirants (although they may have used other products containing parabens), but of those who did, the greatest concentration of parabens was found in tissue samples taken from the outer, upper quadrant of the breast. This doesn’t mean that the parabens caused the women to develop breast cancers, it just suggests there is a correlation. In spite of these concerns, there have been no modern toxicology studies examining the safety of parabens.
Back to the underarm lymph nodes: It seems unlikely that the substances in your antiperspirant actively affect your lymph glands. Lymph glands deal to infections and undesirable biological organisms like bacteria, but they don’t clean out toxic metals or play with artificial hormone mimics. It seems likely that cancers that develop in the breast area migrate TO the underarm lymph glands from the breast rather than the other way around, and that the lymph glands are trying to mitigate the cancer cells. Nevertheless, research DOES suggest that using antiperspirants containing aluminium and/or parabens may increase your risk of developing breast cancer because of their effect on sweat glands and through skin absorption.
For another good summary of these issues, see Dr Mercola’s article on parabens, aluminium, and the breast cancer link. For the “official” story, the American Cancer Society reports “no link between breast cancer risk and antiperspirant use”. You can read their debunking of this “myth” here.
Meanwhile, I’ll continue to use soap and water and forgo spraying or smearing chemical concoctions under my arms.
[i] That’s what the literature says. I DO think the foods you eat play a part. I know some foods, like garlic and curry, make me smell a little pongier than usual the day after I’ve eaten them. Just my personal observation.
[iv] Sappino, A.-P., Buser, R., Lesne, L., Gimelli, S., Béna, F., Belin, D. and Mandriota, S. J. (2012), Aluminium chloride promotes anchorage-independent growth in human mammary epithelial cells. J. Appl. Toxicol., 32: 233–243. doi: 10.1002/jat.1793 http://onlinelibrary.wiley.com/doi/10.1002/jat.1793/abstract;jsessionid=82FFF75E0138F8E3F80056B9EA064379.d03t03?deniedAccessCustomisedMessage=&userIsAuthenticated=false