Do Antiperspirants Cause Breast Cancer?

Do Antiperspirants Cause Breast Cancer?

"Maybe you remember the scary rumors that zipped around the Internet a few years ago claiming antiperspirants and deodorants could cause breast cancer. The claims had several things going for them — the fact that antiperspirants and deodorants are applied in the underarm area, close to the lymph nodes, where cancer cells like to congregate, and in the general vicinity of where most breast tumors develop. Then there were the concerns about parabens and aluminum, both ingredients in these products that are easily absorbed by the skin and which some studies had detected in breast tumors.

Doctors scrambled to help patients understand that the disparate facts did not necessarily coalesce into a coherent whole of cause and effect. Just because the parabens were found in breast tumors, for example, didn’t mean that they triggered the cancer.

The latest research on the matter, published in the Journal of Applied Toxicology, may help to alleviate concerns about underarm products further — or rekindle the worry. U.K. researchers have found that paraben traces are present in the tissue of almost all breast cancer patients, whether or not they use antiperspirants.

Among 160 breast-tissue samples from 40 English mastectomy patients, 99% of samples had traces of at least one paraben, and 60% had traces of five different parabens. Even patients who’d never used underarm products had paraben traces in their breast tissue. That’s not surprising, say the authors, since parabens are found in shampoos, make-up, moisturizers, pharmaceuticals and even some food products, where they are used as a preservative. (If you’re looking for them in your own home, they may be listed as methylparaben, ethylparaben, propylparaben, or butylparaben.)

The new study does not support the idea that parabens cause cancer, despite the incredibly high proportion of patient tissues that contain paraben traces. It’s possible that people without cancer might be equally exposed to the chemicals, so that the tissue levels are no higher among women with cancer than among those who are cancer-free. But the study didn’t include an analysis of breast tissue from women without cancer.

Still, people worry about these chemicals because, in the body, parabens act similar to the female sex hormone, estrogen. Lifelong exposure to estrogen has a reasonably well documented association with breast cancer risk. Some researchers have begun to wonder whether lifelong exposure to parabens might not have a similar effect — and there has been great interest in the last 10 years in testing for such a connection."

in Time