Deodorants and antiperspirants are widely used personal care products for managing underarm sweat and odor. Concerns exist about a potential link between these products and breast cancer, often due to theories about certain ingredients. This article explores the scientific understanding of these claims, examining the components of concern and reviewing available research.
The Ingredients of Concern
Two primary ingredients frequently mentioned in discussions about deodorant and antiperspirant safety are aluminum compounds and parabens. Aluminum-based compounds, the active ingredient in antiperspirants, temporarily block sweat ducts to reduce sweat. The theory suggests these compounds might be absorbed by the skin, especially near the breast, potentially leading to estrogen-like effects. Since estrogen can promote breast cancer cell growth, some scientists theorize absorbed aluminum might contribute to breast cancer development.
Parabens are another class of chemicals used as preservatives in cosmetics, including some deodorants and antiperspirants, to prevent bacterial growth. Laboratory studies show parabens can weakly mimic estrogen activity in body cells. This has led to speculation about their potential to influence breast cell growth and breast cancer risk.
Reviewing the Scientific Evidence
Scientific research has extensively investigated the hypothesized link between antiperspirant use and breast cancer. Most observational studies, including large case-control studies, have found no conclusive association between using underarm antiperspirants or deodorants and an increased risk of breast cancer. For instance, a 2002 study comparing over 800 women with breast cancer to a similar number without the disease found no relationship between breast cancer risk and antiperspirant or deodorant use. A meta-analysis of seven case-control studies also concluded there was no association.
Some earlier studies suggested a possible relationship, such as one from 2003 reporting a younger age at breast cancer diagnosis for women who used antiperspirants frequently or started using them with shaving at an earlier age. However, these studies often have limitations, including their retrospective nature, relying on participants’ memories of past product use. This recall bias can affect reliability, as individuals with cancer might more readily recall exposures they believe are linked to their diagnosis. Studies on aluminum concentrations in breast cancer tissue have also not consistently found higher levels compared to normal tissue, and the source of any detected aluminum is not conclusively established.
Position of Major Health Organizations
Leading health organizations worldwide have reviewed the available scientific evidence regarding deodorants, antiperspirants, and cancer. The National Cancer Institute (NCI) states there is no scientific evidence linking these products to breast cancer development. Similarly, the American Cancer Society (ACS) has concluded there are no strong epidemiological studies to support a connection between antiperspirant use and breast cancer risk.
The United States Food and Drug Administration (FDA), which oversees cosmetic safety, also indicates current evidence does not establish a link between aluminum or parabens in cosmetics and breast cancer. These organizations base their positions on a comprehensive evaluation of existing scientific literature, which consistently shows no definitive causal relationship.