Studies provide contradictory evidence, leading scientists to conclude that more research is necessary
Several years ago, an email made the rounds of the Internet claiming that the aluminum present in deodorants and antiperspirants contributed to the development of breast cancer. Since then, scientists have been researching the claim in attempts to prove or disprove it.
What have they found?
Unfortunately, the answer is not as simple as "Yes, the claim is true" or "No, aluminum is definitely safe." Instead, scientists have been forced to admit that we just don't know either way…yet.
The National Cancer Institute--part of the National Institutes of Health (NIH)--explains that relatively few studies have been done on a link between antiperspirants/deodorants and breast cancer.
A 2002 study showed no increase in the risk of breast cancer in women who used an underarm deodorant or antiperspirant. The scientists reached this conclusion based on interviews they conducted with 813 women who had breast cancer and 793 women who had no history of the disease.
A 2006 study also found no link, though its sample size was smaller at 54 women with breast cancer and 50 women without.
On the other hand, a 2003 study conducted retrospectively with 437 breast cancer survivors found a connection between how often the women shaved under the arms and used an antiperspirant/deodorant and how young they were when they were diagnosed.
And Cancer Research U.K. (CRUK) reported that a 2007 study of 17 women with the disease found higher aluminum levels near the skin, leading the study's authors to speculate about a potential link between cancer and aluminum.
However, CRUK also reports that a 2013 study of 176 women found no significant differences in aluminum levels between the level in the tumor and the level in normal areas in the breast.
Both NIH and CRUK conclude that no strong evidence for a connection between breast cancer and aluminum has been found to date. Because of the conflicting results of the studies that have been done, it is clear that scientists need to do more research before we can say that we have a definitive answer.
In the meantime, there are aluminum-free deodorant products available for consumers who do not want to risk developing cancer. Such products include (but are not limited to) Schmidt's Naturals, Native Deodorant, Meow Meow Tweet (yes, that is the real name), Agent Nateur, and various recipes for those who would prefer to make their own.