You are probably thinking, how can toothpaste be bad? It helps to clean our teeth and fights germs. Without it, our teeth would rot and fall off out of our mouths. We should be thanking the invention of toothpaste instead of criticizing it. Well, after doing some research, I found that there is an ingredient in toothpastes that can have potentially negative effects for your health. This ingredient is called triclosan.

This article explains how the company Colgate-Palmolive removed triclosan from its soap products due to a change in “consumer preferences (Jennings).” Yet, the potentially harmful chemical still remains in their toothpaste products. Some blame was placed on the FDA for approving these products that include triclosan because the FDA used research funded by the actual toothpaste companies that showed that their products were safe. Results from this “research” shouldn’t be relied upon since these companies have to seek the FDA’s approval to sell their products in the first place. So, how exactly is triclosan bad for your health?

Although long term studies with humans have not been done, this study concerning mice showed that large concentrations of triclosan led to increased cancer risk (Jennings). In the study, mice, which were roughly 6 weeks old, were placed in a controlled semi-specific pathogen free room under a constant temperature, 12 hour light and dark cycle, and frequent ventilation before the experiment began (Lee). It is important to keep all these variables constant because if not, then they could possibly have an impact on the results of this study as confounding variables. All the mice (sample size was unspecified) were transplanted with human breast cancer cells (MCF-7) and were randomly assigned to either a control group or a treatment group. The mice in the treatment group were injected with triclosan while the mice in the control group were injected with corn oil. Each group received injections 3 times a week while being observed for 8 weeks. The researchers found that the rats who received triclosan developed much more breast tumors than the ones that received corn oil. Also, the treatment mice had larger and denser tumors. The treatment mice’s tumor tissue was then examined and the researchers found high levels of cyclin D1 expression, which is responsible for cell proliferation. Before the actual experiment on the mice, the researchers isolated the MCF-7 human breast cancer cells in a cell culture and showed that their expression of cyclin D1 increased when they were treated with triclosan. However, levels of p21 expression, which is also responsible for cell proliferation, decreased when treated with triclosan. (I know there is a ton of jargon, but bear with me.)

Even though this was a well designed experiment, I still do not understand why they injected all the mice with human cancer cells in the first place. That kind of defeats the purpose of determining if triclosan causes cancer. I guess that the researchers were trying to prove if breast cancer can get worse under triclosan, instead of proving if triclosan forms cancer in the first place. Nevertheless, triclosan has some sort of connection with cancer. Even though the studies were done with mice, the results show that the topic of triclosan-cancer connection should be stressed much more. The study was well designed. It was not a victim of the file drawer problem because they published evidence that supported the null hypothesis, which was the decreased levels of p21 expression. They could have chose to leave that information out to bolster their case, but they didn’t and rightfully so.

Is there evidence that triclosan, a key ingredient in toothpastes, can be good for you? Of course, we shouldn’t use research that was funded by toothpaste companies to determine if triclosan is safe. This meta-analysis conducted by independent researchers assessed triclosan’s ability to reduce plaque, gingival inflammation, bleeding, etc. The studies consisted of randomized control trials. The meta-analysis consisted of 30 studies and 14,835 people (Riley). In all the studies, there was a treatment group of people who used triclosan included toothpastes and a control group of people who used toothpaste without triclosan. Results were observed for six-seven months. The results showed moderate levels of reduction in the dependent variables listed above but the meta-analysis ultimately concluded that “these reductions may or may not be clinically important (Riley).” In other words, I believe the evidence is not compelling or drastically strong enough to show that triclosan’s benefits outweigh its harmful effects.

Conclusion: In the end, I feel that I should be careful when going toothpaste shopping. 99% of the time, I don’t even think twice about the ingredients listed on my toothpaste. There are a wide variety of toothpastes out there without triclosan that I can use. You can check this out to see which toothpastes I’m talking about. Toothpaste is still beneficial to having clean and healthy teeth; you should just be careful of what’s actually in your toothpaste.

Picture source: http://www.carolinasdentist.com/do-whitening-toothpastes-really-work/