In Korean patients with inflammatory bowel disease, specific pro-inflammatory bacterial taxa (e.g., Escherichia-Shigella, Fusobacterium) are correlated with specific inflammatory metabolites (e.g., TMAO, ceramides), indicating a functional interplay between microbial shifts and biochemical inflammation pathways.

Eating a lot of ultra-processed foods changes the gut bacteria to favor harmful types that produce inflammatory chemicals. These bacteria break down certain food components into toxins like TMAO and ceramides, which damage the gut lining and trigger immune cells to cause ongoing inflammation. At the same time, beneficial bacteria that protect the gut are reduced, removing natural defenses against inflammation.