IS DEODORANT BAD FOR YOU?
Dilvin Yasa looks at some scientific facts and common myths behind these often debated products. Plus, we trial some of the new natural alternatives on the market
Deodorant and antiperspirants have been part of our grooming regimen for more than 100 years, but about 15 years ago, questions arose about their “side effects”.
One popular theory was the aluminium in antiperspirants prevents the body from expelling toxins, which then clog up the lymph nodes and cause breast cancer. While it’s true that sweating is one way that your body gets rid of toxins, Kathy Chapman of Cancer Council NSW says it’s worth noting that “breast cancer starts in the breast and spreads to the lymph nodes, not the other way around”.
Another theory was that the aluminium is absorbed by the skin, affecting the blood brain barrier and linking it with the onset of Alzheimer’s disease.
The stories varied from source to source, but what the Cancer Council claims began as a hoax email soon trickled down to websites and news outlets, causing widespread suspicion of these products, and that remains today. Aluminium has been the common element of concern. This was, in part, prompted by a 2007 study of women with breast cancer that found higher levels of the chemical in areas of the breast nearest the skin, prompting the authors to ponder a possible link. Similarly, a series of studies in the 1960s suggested that aluminium had a tendency to accumulate in the brain tissue of Alzheimer’s patients.
Both ideas were soon disproved. The Alzheimer’s theory couldn’t be replicated in later studies, and scientists concluded there was “no causal relationship” shown between deodorant use and the disease.
The breast cancer study was found to be flawed as not only was it based on just 17 women, but it didn’t compare levels of aluminium in their breasts to other parts of their bodies or to levels in women who didn’t have breast cancer. A larger study of 1606 women satisfied researchers that deodorant use didn’t increase the risk. Lab-based testing and animal models have found that an oft-used antibacterial agent in deodorants, called triclosan, can mimic or interfere with hormones. In one study, published in the journal Chemical Research in Toxicology, researchers found it promoted growth of human breast cancer cells in lab dishes and breast cancer tumours in mice, while other animal studies showed it disrupted hormonal function, and reduced heart muscle function by 25 per cent.
While there’s no evidence yet that triclosan has the same effect in humans, the EU has restricted its use in personal products. The US state of Minnesota recently banned it entirely. It’s still in use in Australia and can be found in some deodorants.