Researchers are uncovering pivotal links between the microbiome and diverse health conditions. Engineered gut bacteria capable of detoxifying methylmercury demonstrate promise for reducing mercury bioaccumulation from fish-rich diets, a novel probiotic application. Gut microbiota influence immunotherapy efficacy in glioblastoma, unveiling microbiome's role in cancer treatment. Studies also reveal how metabolites derived from the gut are enriched in Parkinson’s disease with REM sleep disorder, advancing personalized medicine approaches. Furthermore, investigations into gamma-aminobutyric acid (GABA) modulation highlight microbiome-prebiotic influences on brain disorders, and metabolic dysfunction-associated steatotic liver disease is connected to gut dysbiosis through multi-omics analyses.