You might have heard about the link between aluminum in deodorant and breast cancer. It makes for a terrifying headline—after all, more than 90 percent of Americans use some form of underarm deodorant or antiperspirant, and we count our fresh-smelling selves among that number. If there’s something dangerous lurking in our stick of Secret, we’d certainly want to know about it. We looked into the science surrounding the proposed link between aluminum and breast cancer, and we found some conflicting information. Before you throw out your deodorant, here’s what you need to know.
Why is there aluminum in deodorant, anyway?
Most leading deodorants contain some amount of aluminum salt, which prompts the question: Why? What’s a metallic substance doing in your armpit? The short answer is that aluminum is extraordinarily effective as an antiperspirant. It temporarily plugs up the sweat ducts, leaving you with that nice dry feeling that you’ve come to know and love. Deodorant and antiperspirant are separate things; deodorant gets rid of body odor, while antiperspirant attempts to stop sweat from occurring in the first place. Therefore, you can find deodorants that don’t contain any antiperspirant (more on those in a moment). However, if your deodorant does contain antiperspirant, it likely contains aluminum. Few other ingredients work as effectively, and while aluminum-free antiperspirants exist, they’re rare.
Why are some people concerned about aluminum in deodorant?
We can trace a lot of the controversy to a study conducted in 2005 by Philippa Darbre, PhD, professor emeritus at the University of Reading. Darbre, a breast cancer researcher, noticed that cancer was unusually common in the upper outer quadrant of the breast and suspected that deodorant was somehow responsible. “Aluminum is something that has always concerned me [in deodorants],” Darbre tells HealthyWay. “I don’t know whether it’s aluminum on its own, or the mixture, because there are quite a lot of chemicals in there. But the aluminum is a major concern.” Darbre says that she began studying tumor samples and finding aluminum in just about every one of them. “To cut a long story short, there’s aluminum in every type of breast tissue I can lay my hands on,” she says. “There’s aluminum getting into the human breast. Getting in [in] high quantities. Aluminum is not something that our bodies would normally have in them. The question is, is it harmful or is it not? It’s getting in, but what might it do?” Initially, she believed that aluminum was triggering estrogen receptors. Estrogen exposure seems to be a risk factor for breast cancer, so the hypothesis made sense. Today, however, she believes that aluminum is toxic because it causes a loss of expression of BRCA1, which is a breast cancer susceptibility gene. Darbre is also one of the main researchers behind the anti-paraben movement. In 2004, she identified large concentrations of parabens, a type of preservative substance used in various cosmetics (including deodorants), in human breast tumors. “It’s certainly true when people put these solutions under their arms, they’re not just putting a solution of aluminum,” Darbre says. “They’re putting a lot of other chemicals as well, and those chemicals are going to be interacting. There’s a lot of them in there already that can mimic estrogen action as well, and what we’re looking at with all these things is cocktails of chemicals.”
Does aluminum in deodorant cause breast cancer?
Here’s where things get complicated. Depending on who you ask, the aluminum-in-our-deodorants scare is either totally warranted or completely overblown. Currently, the scales are tilted in favor of “overblown,” but cancer researchers tend to agree that more studies would be helpful. A few examples that turned up in our research:
- In 2014, the German Federal Institute for Risk Assessment (BfR) recommended regulations to limit the amount of aluminum used in antiperspirants. They also recommended that women avoid using antiperspirants after shaving their armpits, hypothesizing that freshly shaved skin would allow aluminum into the body.
- A 2017 scientific review found that “the contention that the use of aluminum-containing antiperspirants promotes breast cancer is not supported by consistent scientific data.” That review also noted that large-scale studies assessing the potential link between aluminum and breast cancer would be beneficial.
- A 2016 systematic review failed to find a link between deodorant use and breast cancer, but researchers noted that they could only find two case-control studies.
We certainly can’t say that aluminum in deodorant is definitively linked with cancer, but we also can’t call this a conspiracy theory; aluminum’s toxicity deserves more research. Currently, though, most authoritative sources we found agree that aluminum is a safe deodorant ingredient, including the National Cancer Institute and the American Cancer Society. We should also note that the U.S. Food and Drug Administration says that current research shows that parabens are safe in cosmetics, including deodorants.
If you don’t want to wear deodorant with aluminum, you’ve got options.
We realize that all of this isn’t exactly a ringing endorsement of the deodorant industry, so if you decide to play it safe, we won’t call you paranoid. Fortunately, you’ve got options. The first and most obvious choice is to stop wearing deodorant altogether. No, seriously: You might not even need it. A study from the University of Bristol found that about 5 percent of people aren’t naturally smelly, thanks to a rare genetic variation (which we’re tempted to call a superpower). If you’re one of the lucky few, you can ditch the deodorant without sending your co-workers fleeing from the office in disgust. Besides, your current deodorant might be doing more harm than good. Some research suggests that regular antiperspirant use has a remarkable effect on your armpit’s microbiome (the bacteria, viruses, and other microorganisms that exist on healthy skin). If that’s the case, you might actually end up being smellier as a result of your deodorant, which obviously isn’t ideal. That’s not to say that you shouldn’t do anything about your odors. “I haven’t used [underarm deodorants] for more than 20 years,” Barbre says. “I use nothing under my arms. I wash with soap and water twice a day, and so far nobody’s complained. I believe the more you use, the more you need.” If you’re not sold on that solution—and yes, we realize it’s a hard sell—consider aluminum-free deodorant options from brands like Tom’s of Maine, Native, Origins, and Schmidt’s. Note that some of these brands also offer deodorants that do contain aluminum, so read the ingredient list carefully. If you want to get away from aluminum but you still want to stop the sweating, check out aluminum-free antiperspirants from brands like HyperDri, which uses tiny proteins called peptides instead of aluminum salts. Be prepared to pay for this state-of-the-art sweat tech though. Finally, remember that cancers are complicated. Dozens of risk factors can influence your risk of developing breast cancer, and things like family history, age, and alcohol use are certainly more significant (and more widely accepted) factors than deodorant use. Keep that in mind the next time you hear that a certain substance or ingredient “causes cancer.” Chances are good that the actual science is a whole lot more complicated than that.
