Forgetting the Difference Between Mice, Men, and Women

The difference between mice, men, and women is eluding health journalists who are churning out headlines about common food ingredients — emulsifiers — causing obesity, metabolic syndrome, and inflammatory bowel disease.

The study that prompted this enthusiastic reporting probes the effects of two very common emulsifiers — cellulose gum and polysorbate — on the microbiome in the guts of mice. Benoit Chassaing and colleagues showed that these emulsifiers could bring changes in gut microbes that caused low-grade inflammation, obesity, and metabolic syndrome in their mice. They also found that the emulsifiers could promote colitis in mice that are predisposed to it.

Unfortunately, the investigators overreached a bit with their concluding statement:

The broad use of emulsifying agents might be contributing to an increased societal incidence of obesity/metabolic syndrome and other chronic inflammatory diseases.

Though this is interesting research, it’s a long stretch from small numbers of mice to a global epidemic of obesity in humans. Professor Tom Sanders of Kings College London characterized those conclusions as “headline grabbing and unwarranted” based on the “trivial amounts of these additives” in food. He points out that the amounts of emulsifiers fed to the mice in these experiments are 250 times the daily limits for human consumption.

Having a personal preference for minimally processed foods is certainly reasonable. Research on mechanisms for microbes to influence obesity is valuable. But overstating the significance of animal studies through aggressive PR simply sows confusion and skepticism about important scientific research.

Click here to read more from Food Navigator and here to read the study in Nature.

Pannekoeken Bakken, illustration by Rein Stuurman from janwillemsen / flickr

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