Reasonable Doubts About Emulsifiers?

A new study in Gastroenterology is adding fuel to the fire of doubts about emulsifiers in processed foods. A diverse group of researchers conducted an RCT of a diet enriched with an emulsifier called carboxymethylcellulose. CMC and cellulose gum are two other names for this ingredient. Nine subjects received the control diet with no emulsifiers for 11 days. Seven received the very same diet enriched with 15 grams of CMC per day. The researchers, led by Benoit Chassaing, found reason for doubts about CMC as an innocuous food additive.

They found changes in gut microbiota and a possible signal of gut inflammation in two subjects. They conclude:

“These results support the notion that the broad use of CMC in processed foods may be contributing to increased prevalence of an array of chronic inflammatory diseases by altering the gut microbiome and metabolome.”

A Ubiquitous Food Ingredient

It might be hard to find a more common food ingredient than CMC. Most often you will see it in the ingredient list as cellulose gum. It’s in ice cream, bread, cakes, yogurt, beverages, and many other foods where a creamy texture is desirable. It helps low-fat foods seem richer.

In 2018, the European Food Safety Authority published an updated assessment of CMC and related cellulose food additives. They found no safety concerns.

Writing in The Conversation, Dominic Partridge and Alex Johnstone describe reasons for concerns about emulsifiers, but conclude “it still far too early to say we should stop eating them.”

A Grain of Salt

Though we are paying attention to this research, we are also taking it with a grain of salt. We have a few reasons. First, this is a very small study. Only seven patients received the CMC-enriched diet and only for 11 days. Also, the dose of CMC, 15 grams per day, “likely exceeds” what most people would consume, as the authors tell us. Finally, the response to this ingredient is most likely very different in different people – “highly personalized,” in the words of these researchers.

So yes, this is important research to follow. But right now, the evidence is too fragmentary to justify serious doubts about the safety of emulsifiers, which are omnipresent in the food we eat. Chassaing feels strongly about these concerns, but writes that “more work is needed.” We agree with him on that point.

Click here for the study, here for further reporting, and here for perspective on CMC.

The Egg, painting by Odilon Redon / WikiArt

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December x, 2021