By Jesica Levingston Mac Leod, PhD
Body odors (BO) are part of our evolution, and the ability to smell has evolved with us, making people fall in love or run away from a smelly person. Sweat has an initial effect to cool our body down and avoid overheating. Sweat can also be trigger by stress, anxiety or other hormonal changes. Sweat by itself doesn’t smell, but the bacteria located near the glands, for example, the armpits, breakdown the sweat generating the “BO”. How do we deal with the stinky fact? We apply deodorants and/or antiperspirants. Deodorants have ingredients like triclosan, which make the skin more salty or acidic for the bacteria to grow in those areas. Therefore deodorants don’t stop you from sweating, but antiperspirants will do the trick, as they contain ingredients like aluminum and zirconium, which are taken up through the pores and they react with water and swell, forming a gel that blocks the sweat.
Last year, Mandriota and collaborators demonstrated that in a cancer mouse model, concentrations of aluminum in the amount of those measured in the human breast are able to transform cultured mammary epithelial cells, allowing them to form tumors and to metastasize. Moreover, aluminum salts have been linked with DNA damage, oxidative stress, and estrogen action. In 2004, a woman reported aluminum poisoning after using antiperspirants for four years, and after stopping the use of these products the aluminum levels dropped and she recovered.
Breast cancer develops after cells with mutations in their DNA start growing uncontrolled, generating a tumor. Most breast cancers develop in the upper outer quadrant of the breast, near to the lymph nodes that are exposed to antiperspirants. This fact was the starting point for the theories that the underarm cosmetic products could be carcinogenic. One of the first publications on this subject dates from 2002; it was population-based (ages 20-74, 1606 patients) and found no correlation between breast cancer and antiperspirant use. A second article found a relationship between an earlier age of breast cancer diagnosis to more frequent regular use of antiperspirants/deodorants and underarm shaving.
Aluminum salts have been linked to increased risk of developing breast cancer, but so far the research on this has been quite inconsistent. Last month, a new research study of 418 women (ages 20 to 85) examined their self-reported history of use of underarm cosmetic products and health status, in order to unveil a bit more about the link between antiperspirants and breast cancer. Linhart and col. from Austria, studied the relationship of the use of underarm cosmetic products and the risk of breast cancer. They divided the group in two: half of the women were breast cancer patients and the other half healthy controls. Then, they measured the concentration of aluminum in the breast tissue of some of the women. The results showed that the risk of breast cancer increased by an odd ratio of 3.88 in females who described using the underarm products multiple times per day starting before their 30th birthday. Importantly: “aluminum traces were found in the breast tissue in both cancer patients and healthy controls and it was significantly associated to self-reported underarm cosmetic products use”. In fact, the median concentrations of aluminum were 5.8 (2.3-12.9) nmol/g in the tissues from breast cancer patients versus 3.8 (2.5-5.8) nmol/g in controls. The conclusion is that more than daily use of these cosmetic products at younger ages may lead to the accumulation of aluminum in breast tissue and increase the risk of breast cancer.
Although the American Cancer Society claims that “there are no strong epidemiologic studies in the medical literature that link breast cancer risk and antiperspirant use”, after the Linhart investigation, and knowing that 1 in 8 women will be diagnosed with breast cancer in her lifetime, I will avoid antiperspirants with aluminum. Nobody wants to be called “stinky”, so some actions to take are to wash your clothes after working out, take showers regularly and/or clean your armpits with water and soap as soon as you “smell something”, apply deodorant, and consult with your doctor about the best way to keep your body odors under control. The last resource: perfume. If you can’t win the fight… hide.