Preventive Medicine 2.0 Starting from the Gut: Does Dietary Fiber Work Differently for Each Person? The Era of "Precision Microbiome" That Also Changes Mental Health

The analysis of the gut microbiota (microbiome) and research on the gut-brain axis are advancing, making personalized preventive medicine increasingly feasible. Shotgun metagenomic analysis allows for the understanding of not only the "presence" of bacteria but also their metabolic functions, enabling the design of personalized prebiotics, probiotics, postbiotics, and dietary plans. It has been shown that responses to prebiotics, such as inulin, vary significantly among individuals, prompting a shift away from standardized dietary guidance. AI enhances risk prediction by integrating metagenomics, blood metabolites, and immune indicators, expanding applications like improving the accuracy of colorectal cancer screening. On social media, there is a coexistence of optimism and caution, with ease of use and transparency of evidence being key factors. Moving forward, governance that connects the PDCA cycle of testing, intervention, and re-testing to clinical practice will be crucial.