Dr. McGrath's Study Summary

An earlier age of breast cancer diagnosis related to more frequent use of antiperspirants/deodorants and underarm shaving
European Journal of Cancer prevention 2003 12:479-485

Bullet points:

Breast Cancer Incidence suggest a lifestyle/environment cause

The closest lifestyle to the breast is underarm hygiene
The closest environment to the breast is the underarm

Since 1940 when sales of antiperspirants/deodorants are plotted vs. breast cancer incidence, they are essentially parallel

The McGrath study grouped breast cancer survivors into 4 groups based on intensity of underarm product usage and shaving. If this environment/lifestyle plays a role in breast cancer, the more active underarm hygiene groups should develop the disease at an earlier age.

Results:

1. The most active Caucasian group was diagnosed 22 years earlier then the group that did not shave underarms and apply antiperspirants/deodorants. Between the same all race groups the diagnosis was 15 years earlier

2. Comparing the age of diagnosis in beginning these habits before or after age 16 revealed within the most active hygiene group a 19 year earlier diagnosis in those beginning the habits before age 16.

3. Plotting the average age of breast cancer diagnosis in the US vs. underarm activity revealed a lower age of diagnosis in those who used antiperspirants/deodorants and shaved and a higher age of diagnosis in non-users/non-shavers

4. The breast cancer incidence plotted against body hair differences by race/ethnicity reveals less breast cancer in those with less body hair- those who would likely shave less or not at all


Comment: A small retrospective study such as this cannot conclusively link a woman’s underarm hygiene habits to breast cancer. Though as a pilot study it raises suspicions supporting alternative habits and product usage.