GLOSSARY

Metabolomics measures small chemicals, whose host, food and microbial origins are not always distinguishable without design.

Metagenomics studies community genetic potential, metatranscriptomics RNA and expression, metaproteomics proteins, and metabolomics chemicals. These layers answer different questions rather than replacing each other. RNA or protein alone does not necessarily quantify net pathway flux. Combine layers with diet, timing and human outcomes; the omics label itself guarantees neither clinical validity nor accurate supplement advice. Measurement breadth and actionable benefit remain separate properties.

Composition identifies detected groups; functional potential concerns genetic capacity, while activity concerns what is actually expressed or produced. Different communities can share functions. A gene's presence does not guarantee a particular metabolite output. Organism names alone therefore establish neither extra usable energy nor improved absorption, strength or recovery. Distinguish taxonomic detection, measured activity and meaningful human outcomes when assessing a microbiome claim.

Ribosomal marker sequencing commonly profiles bacteria and some archaea depending on primers and methods, not all viruses and fungi. Shotgun sequencing reads broader sample DNA and can add functional information, still depending on depth and references. Neither method's name alone provides diagnosis or a personal food prescription. Species and strain resolution need clarification, and broader detection does not mean every reported gene is expressed or every organism is active.