If you use an antiperspirant that contains aluminum, you could be increasing your risk of breast cancer. Antiperspirants work by clogging, closing, or blocking the pores that release sweat under your arms — with the active ingredient being aluminum. Not only does this block one of your body’s routes for detoxification (releasing toxins via your underarm sweat), but it raises concerns about where these metals are going once you roll them (or spray them) on.
Research, including one study published this year in the Journal of Applied Toxicology, has shown that the aluminum is not only absorbed by your body, but is deposited in your breast tissue and even can be found in nipple aspirate fluid a fluid present in the breast duct tree that mirrors the microenvironment in your breast. Researchers determined that the mean level of aluminum in nipple aspirate fluid was significantly higher in breast cancer-affected women compared to healthy women, which may suggest a role for raised levels of aluminum as a biomarker for identification of women at higher risk of developing breast cancer.
In a 2007 study published in the Journal of Inorganic Biochemistry, researchers tested breast samples from 17 breast-cancer patients who had undergone mastectomies. The women who used antiperspirants had deposits of aluminum in their outer breast tissue. Concentrations of aluminum were higher in the tissue closest to the underarm than in the central breast.
Aluminum is not normally found in the human body, so this study was a pretty clear sign that the metal was being absorbed from antiperspirant sprays and roll-ons. Please note that aluminum is typically only found in antiperspirants. If you are using a deodorant-only product it is unlikely to contain aluminum but might contain other chemicals that could be a concern.
Aluminum salts can account for 25 percent of the volume of some antiperspirants, and a review of the common sources of aluminum exposure for humans found that antiperspirant use can significantly increase the amount of aluminum absorbed by your body. According to the review, after a single underarm application of antiperspirant, about .012 percent of the aluminum may be absorbed.
This may not sound like much until you multiply it by one or more times a day for a lifetime, which adds up to massive exposure to aluminum — a poison that is not supposed to be in your body, and may be more toxic than mercury. Aluminum salts can mimic the hormone estrogen, and chemicals that imitate that hormone are known to increase breast cancer risk. Animal studies have also found that aluminum can cause cancer. Aside from vaccinations, your antiperspirant may be your largest source of exposure to this poisonous metal!