Sound the alarm! In a pivotal new report, we now have direct, clear evidence that a commonly used food additive, carboxymethylcellulose (CMC), quickly disrupts the gut microbiome in healthy subjects. 

A slew of recent reports in animal studies have indicated that the ubiquitous family of food additives called emulsifiers radically alter gut bacteria and the intestinal lining, fostering a wide range of diseases including colon cancer, colitis, and obesity. 

To evaluate in humans, scientists performed the following clinical trial. A small group of healthy adults were placed on one of two test diets while housed in a clinical research center. Their diets were identical except that one contained added CMC. The scientists performing the study were focusing on the impact of CMC on the study subjects’ gut bacteria and its beneficial metabolites. 

The results? Consuming the CMC significantly altered gut microbes. Specifically, there was a notable reduction in select species of gut microbes and an alarming depletion of a family of vital gut metabolites called short-chained fatty acids, essential for maintaining a healthy gut lining. 

What’s more, colonoscopies performed on the study subjects before and after the two-week study showed that a subset of the CMC consuming study subjects displayed bacteria within their gut mucous lining—a pathologic feature of inflammatory bowel disease and other inflammation-based conditions. 

What you should do—Avoid processed foods containing CMC, sometimes called cellulose. Check food labels. The list is long, but common culprits are sauces, ice cream, frozen yogurt, breads, cakes, biscuits, margarine, and peanut butter. It is likely that most food additive emulsifiers will have the same effect. Thus, why the best approach is to avoid all foods that come out of a factory!

Gastroenterology, 2021; DOI: 10.1053/j.gastro.2021.11.006