Americans spend $18 billion a year on deodorant and antiperspirant in a quest to cover up body odor and reduce sweating.1 For many, applying deodorant is a regular part of their morning routine, but it hasn’t always been this way.
The first deodorant, which killed off odor-producing bacteria, wasn’t introduced until 1888. The first antiperspirant, which reduces both bacterial growth and sweat production, came about 15 years later. Even then, however, most people were wary of applying such products to their underarms.
In 2016, we’ve come full circle in a sense, as some people are realizing that applying various personal care products every day isn’t always necessary, effective or, importantly, healthy. Do you need to worry about the health risks of applying your deodorant?
Antiperspirants May Kill Off Beneficial Armpit Bacteria
It’s becoming widely known that your body’s microbes play an intricate role in your health. You cannot survive without them, and it’s best to work with them, for instance by eating fermented foods and avoiding antibacterial soaps, rather than killing them off indiscriminately.
Researchers recently revealed, however, that habitual use of deodorants and antiperspirants has a significant effect on armpit bacterial density and variation.
For starters, when use of such products was discontinued, there was a marked increase in bacterial density, approaching that which was found among individuals who regularly do not use any such products.
When antiperspirants were applied, bacterial density dramatically declined and differences in the types of bacteria were also noted. According to the study, which was published in the journal PeerJ:4
” … [I]ndividuals who used antiperspirants or deodorants long-term, but who stopped using product for two or more days as part of this study, had armpit communities dominated by Staphylococcaceae, whereas those of individuals in our study who habitually used no products were dominated by Corynebacterium.
Collectively these results suggest a strong effect of product use on the bacterial composition of armpits.
Although stopping the use of deodorant and antiperspirant similarly favors presence of Staphylococcaceae over Corynebacterium, their differential modes of action exert strikingly different effects on the richness of other bacteria living in armpit communities.”
There’s still a lot to learn about what health effects this microbial tweaking may cause, although it’s known that Corynebacterium bacteria, which produce body odor, may help protect against pathogens while Staphylococcaceae bacteria can be beneficial or dangerous.5
Antiperspirants May Increase Odor-Producing Bacteria in Your Armpits
The reason your sweat smells is because the bacteria living in your armpits break down lipids and amino acids found in your sweat into substances that have a distinct odor.
Antiperspirants address this problem using antimicrobial agents to kill bacteria and other ingredients such as aluminum that block your sweat glands. However, separate research has revealed antiperspirants affect the bacterial balance in your armpits, leading to an even more foul-smelling sweat problem.6
Those who used antiperspirants saw a definitive increase in Actinobacteria, which are largely responsible for foul-smelling armpit odor. Other bacteria found living in people’s armpits include Firmicutes and Staphylococcus, but the odors they produce are milder, and they’re not produced quite as readily.
It turned out the less odor-causing bacteria may be killed off by the aluminum compounds (the active ingredient in most antiperspirants), allowing bacteria that produce more pungent odors to thrive instead.
In some participants, abstaining from antiperspirant caused the population of Actinobacteria to dwindle into virtual nonexistence.
This means using an antiperspirant may make the stink from your armpits more pronounced, while quitting antiperspirants may eventually mellow the smell. The researchers explained in Archives of Dermatological Research:7
“A distinct community difference was seen when the habits were changed from daily use to no use of deodorant/antiperspirant and vice versa … Antiperspirant usage led toward an increase of Actinobacteria, which is an unfavorable situation with respect to body odor development.
These initial results show that axillary cosmetics modify the microbial community and can stimulate odor-producing bacteria.”
Is There a Link Between Antiperspirant and Cancer?
If you look at the ingredients in your antiperspirant, you’ll likely find that it contains aluminum, which acts as a “plug” in your sweat ducts to reduce sweating.
Aluminum antiperspirants may act as a long-term source of exposure to aluminum, which research suggests may accumulate in breast tissue in women.
This is problematic for a number of reasons, as aluminum may cause alterations to DNA as well as epigenetic effects that could potentially support cancer development.8
Aluminum (specifically aluminum chloride and aluminum chlorohydrate) is also known to interfere with estrogen receptors in breast cancer cells, and estrogen plays a well-known role in breast cancer.
Studies also show a high incidence of breast cancer in the upper outer quadrant of the breast, nearest to where antiperspirants are applied, together with “genomic instability.”9 Back in 2005, researchers concluded:
“Given the wide exposure of the human population to antiperspirants, it will be important to establish dermal absorption in the local area of the breast and whether long term low level absorption could play a role in the increasing incidence of breast cancer.”
In 2013, researchers found increased levels of aluminum in nipple aspirate fluid from women with breast cancer compared to women without the disease. They also detected increased levels of inflammation and oxidative stress, noting:10
” … [O]ur results support the possible involvement of aluminum ions in oxidative and inflammatory status perturbations of breast cancer microenvironment, suggesting aluminum accumulation in breast microenvironment as a possible risk factor for oxidative/inflammatory phenotype of breast cells.”
Parabens in Deodorant May Be Linked to Breast Cancer
Parabens are preservatives that are found in many antiperspirants and deodorants. These chemicals have estrogenic activity in human breast cancer cells, and research published in 2012 found one or more parabens in 99 percent of the 160 tissue samples collected from 40 mastectomies.11
Separate research also detected parabens in 18 of 20 tissue samples from human breast tumors.12
While a definitive link hasn’t been made, the growing collection of research suggests caution is warranted. Considering chemical antiperspirants and deodorants are an optional product, it may be a risk that’s not worth taking.
Are Natural Deodorants Safe?
In general, deodorants may be somewhat safer than antiperspirants simply because they don’t typically contain aluminum. There are many brands of aluminum-free antiperspirants on the market, as well, and some of these are safer alternatives. However, be aware that aluminum is just one of the toxic ingredients in personal care products — you can find other chemical toxins to avoid in your personal care products in the infographic below.
Alternatively, just use plain soap and water. This is what I use, typically in the morning and after I exercise. A paste made from baking soda and water also works as a natural deodorant.