The chemicals in question are the preservatives parabens, which are added to personal care products and some processed foods to prevent bacterial growth. Though they aren't as well researched as chemicals like bisphenol A, "parabens are estrogenic," says Lynn Carroll, PhD, senior scientist at The Endocrine Disruption Exchange, a nonprofit that researches hormone-mimicking chemicals. And they build up in breast milk. "That is concerning because whoever's eating the breast milk gets a dose, and those children are at a very vulnerable stage in their development."
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Too much estrogen in your system can be responsible not just for breast cancer, but for other dangerous conditions such as malignant melanoma (ironic, considering that parabens are commonly used in sunscreens) and male reproductive disorders. A November 2010 study in the journal Environmental Health Perspectives found that parabens can damage sperm in mice.
In this most recent study, researchers from the University of Reading, in the UK, collected 160 samples of breast tissue taken from women who'd had mastectomies and tested them for the presence of five different parabens. At least one form of paraben was present in 99 percent of the tissue samples, and all five were present in 60 percent of the samples. What was concerning, the authors added, was that one paraben, propylparaben, existed in much higher levels in the axilla region of the breast, the area closest to the armpit, which is the area where, according to the authors, a high percentage of tumors are found.
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Of course, their mere presence doesn't mean that parabens cause breast cancer, writes the study's lead author, Phillipa Darbre, PhD, professor in the School of Biological Sciences at the University of Reading. "It would seem unlikely that any one chemical would play a dominant overall role," she adds. But understanding which chemicals are being detected in breast tumors, and where they are, helps scientists better understand the environmental causes of breast cancer and how chemicals may influence the disease.
For instance, Carroll says, another type of chemical used in deodorant fragrances, phthalates, can increase your skin's absorption of parabens. The parabens enter your bloodstream and attach themselves to the nearest estrogen receptor and cause problems. "Estrogen receptors are all over your body, but certainly, breast tissues have lots of them," she says.
Deodorant manufacturers have slowly been removing parabens from their products, and both men and women are starting to ask for "paraben-free" deodorants, according to the marketing research firm Mintel. But why wait for the industry to catch up with science?
Make Your Own Organic Beauty Products
You can find paraben-free deodorants at a natural foods store, but you can stay healthy and save even more money with these natural deodorant alternatives:
• Baking soda. Baking soda's alkaline properties make it especially effective at breaking up odor molecules—that's why it's so good at deodorizing refrigerators, trash cans, and just about anything else in your home that smells. The sodium in baking soda can dry out your skin; if that happens, mix it with some paraben-free body lotion, or try making your own deodorant cream using baking soda, coconut oil, and shea butter.
• Apple cider vinegar. Dabbing apple cider vinegar under your arms after you shower may inhibit odor-causing bacteria from growing on your skin. Apply it lightly with a cotton ball and wait a few minutes for the smell to dissipate.
• Vodka. The ethyl alcohol in vodka and other spirits is commonly used in air fresheners, and it has the same effect as a deodorant. Vodka is also odorless, for the most part, and you can mix in your favorite essential oils if you'd like to add fragrance. Alcohol can be drying, however, so if spritzing vodka under your arms leaves you with a rash, try diluting it with distilled water.
• A good shave. Body odor is caused by a combination of bacteria and perspiration, and body hair creates a lot of heat, which leads to more perspiration. Keeping your pits groomed, even if you're a guy, can help cut down on body odor and make you less dependent on deodorants in general.