When researchers first posited a link between underwire bras and breast cancer, some speculated that a too-tight fit might interfere with lymph drainage. They believed that the obstruction might allow toxins to get trapped in breast tissue and be a contributor to cancer.
The claim was later debunked, but now scientists are investigating another potential cause for concern: that the metal in some underwire bras magnifies exposure to wireless radiation, such as the kind emitted from Wi-Fi hot spots and cell phones.
The theory isn’t as far-fetched as it seems, says Devra Davis, PhD, the founder and president of Environmental Health Trust. “We know from studies conducted by researchers in Switzerland and at the University of Utah that metal objects will extend and magnify exposure to wireless radiation,” she says. “We also know that such radiation stimulates the growth of breast cancer cells.”
Davis adds that the radiation may also interfere with melatonin production, a hormone that helps repair DNA damage. This, too, could increase the risk of breast and other cancers.
While more research must be done to assess this link, the work is part of a growing number of studies looking at the potential health dangers of wireless radiation and the magnifying power of metal.
Until the question is answered definitively, Davis advises putting some distance between you and your cell phone. “Use a speakerphone or a headset on calls, and don’t keep your phone on your body” — or near a metal-supported bra.
Davis says there’s no need for women to ditch their underwire bras entirely (especially since some of them use plastic, not metal), but she recommends erring on the side of caution and swapping them out for different types of support whenever the opportunity arises.