Antiperspirant And Even Deodorant Change Our Microbiome, Might Impact Health

Dawn Papple

Wearing antiperspirant or deodorant significantly alters your armpits' microbiome, which might seem like the goal, but it could have major effects on you besides just keeping you smelling fresh and feeling dry, researchers say. A study conducted by researchers at North Carolina State University, the North Carolina Museum of Natural Sciences, North Carolina Central University, Rutgers University, and Duke University claim that antiperspirant and deodorant significantly influence both the type and quantity of bacteria that live in your pits, and that, they say, may not be a good thing.

"We wanted to understand what effect antiperspirant and deodorant have on the microbial life that lives on our bodies, and how our daily habits influence the life that lives on us," corresponding author of the paper published in PeerJ, Julie Horvath, who is head of the research laboratory at the NC Museum of Natural Sciences and an associate research professor at NC Central, said. "Ultimately, we want to know if any changes in our microbial ecosystem are good or bad, but first we have to know what the landscape looks like and how our daily habits change it."

— Socks On An Octopus (@socksonoctopus) October 5, 2015

"Just which of these species live in any particular armpit has been hard to predict until now, but we've discovered that one of the biggest determinants of the bacteria in your armpits is your use of deodorant and/or antiperspirant," the professor of applied ecology at NC State, Rob Dunn, who co-authored the paper, said in the press release.

While a Health editor stated that effects are not seen with deodorant, Horvath indicated in the press release that our microbiome does change with both antiperspirant and deodorant, along with many other human interventions we practice for hygiene.

"We found that, on the first day, people using antiperspirant had fewer microbes in their samples than people who didn't use product at all – but there was a lot of variability, making it hard to draw firm conclusions. In addition, people who used deodorant actually often had more microbes – on average – than those who didn't use product."

Horvath did specify that once all of the study participants began using antiperspirant on days seven and eight of the study, very few microbes could be found in the participant's armpits, according to Discovery. Meanwhile, genetic sequencing found that the bacteria found in the participants varied depending on their antiperspirant and deodorant, according to the press release.

They found that the people who hadn't worn deodorant or antiperspirant had mostly Corynebacteria on their underarms, followed by various Staphylococcaceae bacteria. Corynebacteria do cause people to have an odor that we have come to decide is an undesirable scent, but they are also believed to play a big role in defending our bodies from pathogens. Staphylococcaceae are a very diverse group of bacteria. They are found all over human skin. Sometimes they can pose a health risk, but overall, the researchers stated, this group of bacteria is also considered beneficial to our health.

So, while you will smell better, your armpits may experience a decreased resistance to pathogens, according to the findings. An earlier Inquisitr article reported that a different study found that using deodorant might lead to cancer.

— OPD News Feed (@OPDNewsFeed) June 17, 2015

"Using antiperspirant and deodorant completely rearranges the microbial ecosystem of your skin – what's living on us and in what amounts," Horvath says.

According to the PeerJ research paper, "Whether antiperspirant or deodorant tends to favor less beneficial or even pathogenic bacterial species does not seem to have ever been considered," and that earlier research indicates that that the microbial environment on our skin has a "significant influence on human health and disease."

[Photo by Austin_photoguy50 | Flickr | CC 2.0 | cropped]