We've all heard the big debates on natural products vs. chemical ones. In reality, a lot of these chemicals, including the ones in beauty products, have not been studied in depth and researchers are only beginning to scratch the surface the underlying problems they can create over a lifetime of use. So what does a Yale dermatology doc have to say about all of this deodorant/cancer hubbub?

According to an MSN interview with Dr. Lisa Donofrio, a Yale University School of Medicine assistant clinical dermatology professor, "Small studies have suggested that daily use of these products might raise a woman's risk for breast cancer over time."

The culprit? Preservatives called "parabens" that are found in nearly every beauty product. Parabens prolong product shelf life, sure. But the Doc says the problem is that these preservatives are, "estrogenic, meaning they will bind to estrogen receptors [on cells], and in test-tube studies, they actually stimulate breast cancer cells."

If you have been using a paraben filled product, don't worry. Donofrio claims that in most products "[parabens are] just in too small amounts to cause any problems." She then goes on to say, "But over a lifetime, with daily use of these creams, we don't actually know what the cumulative dose really is."

Our suggestion? Finish up that bottle of cream and stick of deodorant, then move onto a preservative free formula.

Via MSN