Just in time for Thanksgiving we learn that two more common food additives present a threat to our health and the health of our families. Have you rushed to your refrigerator and pantry to check out the ingredient lists? Perhaps the scariest headline was on the Time website:
From the article we learn that polysorbate 80 and carboxymethylcellulose represent a larger group of chemicals, known as emulsifiers, which are added to many processed foods. According to the article “emulsifiers create the ideal conditions for triggering colon cancer in mice.” So it may not be enough to just avoid carboxymethylcellulose and polysorbate 80, we may also need to avoid all emulsifiers to reduce our chances to get cancer. Note, that there is a subtle change from the headline above about causing cancer to the statement in the text that they created conditions for triggering the cancer in mice. So is the headline right or is it misleading?
Spread 55% Vegetable Oil
In searching for a report on the news release from the researchers at Georgia State University, I found a more nuanced headline:
But that headline seems to obscure the comment in the text of the article that
Overall, these findings support the concept that agitating host-microbiota interactions to cause low-grade gut inflammation can promote colon carcinogenesis.
So now we learn that instead E (Emulsifiers) causing C (Cancer) presumably in humans as indicated by the Time headline even that E doesn’t necessarily create IC (Ideal Conditions) for triggering C in mice. What the press release suggests that the scientists think that E affects GM (Gut Microbes) which in turn can lead to minor I (Inflammation) that could increase the chances of a tumor in G (Gut) in M (mice) and possibly even in H (humans). That seems to be a lot of speculation and way too many dots to connect.
Wait, we are not finished yet! I went back and read the original article that will appear in Cancer Research1. The two chemicals did NOT cause any cancer. The researchers deliberately challenged these mice with carcinogens. Mice that were challenged with carcinogens and either polysorbate 80 or carboxymethylcellulose showed more tumors in mice after they were euthanized and the colons examined than those challenged with the carcinogens in the water control. Neither the water nor the emulsifiers appeared to cause cancer without the added carcinogens. The article concludes that:
Hence, we propose that numerous factors that induce low-grade inflammation, including consumption of dietary emulsifiers, may promote a hostile environment in the colon by modifying the microbiota composition, leading to a low-grade intestinal inflammation and alterations in the therefore creating a favorable niche for colonic tumorigenesis.
As in many scientific articles, there are many mays, buts, mights, coulds and maybes to justify the scary headlines. As I learned as a reporter for my college newspaper, editors and not the reporters themselves write the actual headlines. Editors are prone to sensationalize. I am all in favor of continuing this research to see if such chemicals really pose a danger to our health, but the concerns raised seem to be premature based on the results gathered to date.
Science does not provide instant answers. A single study like this one raises many interesting questions but provides few, if any, clear answers. A single research study is like a single piece in a jigsaw puzzle. If the results are provocative enough, other experiments will be conducted either to verify or refute the conclusions of the original work. Eventually a pattern will emerge that will be generally accepted by the scientific community in this specific field. If the conclusions made by the Georgia State group become more definitive, it will be a signal to the FDA to decide if these two additives or even if all emulsifiers should be removed from foods. It seems to me that we are a long way from such a conclusion.
From what I have been able to read, this is what I now know
- The study was with mice and not with humans.
- Added carcinogens caused the cancer and NOT the two chemical additives.
- These additives appear to be acting in a similar fashion based on similar chemical properties.
- These emulsifiers appear to have made it easier for the carcinogens to cause the cancer, but it is not clear how they act to produce such a result.
- The action of these compounds appears to be at the interface of the gut and the microbes present in the gut.
Every research study raises questions for scientists who read the article. The questions that need to be answered to my satisfaction include
- Are polysorbate 80 and carboxymethylcellulose “creating a favorable niche” as random effects of two compounds, based on their status as emulsifiers, or on another property such as surfactants?
- Will natural emulsifiers like egg yolks do the same thing?
- Is the interaction described due to the additives making the carcinogens more potent or the gut microbes and the intestinal linings more susceptible?
- Is the addition of the two compounds to water work the same in our guts as their presence in food after digestion or is it merely due to the experimental conditions?
- Are these results applicable to humans in a similar way they are to mice? If so, should they be removed from processed food?
I found that [Emulsifiers (Vegetable Mono- and Diglycerides, Soy Lecithin)] were listed as ingredients on the spread in my refrigerator and that [Sunflower Lecithin], another emulsifier, is an ingredient in the almond milk in my pantry. I did not find either polysorbate 80 or carboxymethylcellulose on any of my many processed foods and ingredients in either place. In my next post I will discuss the importance of why the answers to these questions are important and why I am not concerned yet about these ingredients in my processed foods. I suspect that food scientists working for Big Food are looking for acceptable substitutes for theses additives. Don’t be surprised if you see ARTIFICIAL EMULSIFIER FREE or NO POLYSORBATE soon on a product label at supermarket near you.
Next week: Emulsifiers and surfactants
1 Viennois, E., D. Merlin, A.T. Gewirtz and B. Chassaing, 2016, Dietary emulsifier-induced low-grade inflammation promotes colon carcinogenesis. Cancer Research In press (date of electronic publication 2016 Nov 7)