GLOSSARY

Immune Homeostasis balances immune activation and control dynamically, not maximal stimulation of every component.

Mucosal immunity coordinates pathogen defense with tolerance of foods and commensals, involving intestinal lymphoid tissue and secretory antibodies. Indiscriminately boosting every response is not desirable, and immune tolerance is not identical to symptom-free digestive tolerance. Athletes also need sufficient energy, sleep and training-load management. A bacterial name or isolated marker does not guarantee freedom from infection or replace assessment of recurring illness and dietary adequacy.

Cytokines signal across immune and other tissues, with effects depending on site, timing and context. A transient exercise interleukin rise is not equivalent to chronic disease inflammation; muscle-derived signals can have different regulatory roles. Pro- and anti-inflammatory labels are contextual summaries. Nutrition does not aim to eliminate every inflammatory signal, and post-session values require sampling context rather than automatic interpretation as damage or a need for suppression.

Microbes interact with substrates, chemistry, the host and one another, rather than forming a simple good-versus-bad list. Cooperation, competition and use of another organism's products coexist. A species' effect depends on strain, location and context. In sports nutrition, a varied tolerable dietary pattern is more useful than maximizing one bacterial name without human evidence. Ecological relationships cannot be inferred from a single abundance measurement alone.

The intestinal barrier permits selective exchange while mucus, cell junctions and immunity limit inappropriate passage. Complete closure is not its physiological goal. Some claudins form selective pathways, and junction proteins have different roles. Increased expression of one protein in an experiment does not prove complete human barrier function. Functional measures and personal context remain necessary alongside molecular names when judging a proposed nutrition intervention.

If symptoms recur, record food, medicines, training timing and bowel patterns; match intervention to cause and evidence while maintaining sufficient energy during assessment.

An association between microbes and health or performance does not alone establish microbial causation. Diet and training can influence both, and culture or animal findings are not direct human prescriptions. Sports-benefit claims need relevant human outcomes for the actual intervention. An axis name or biological pathway cannot replace evidence of a practical effect, especially when a product is marketed using results from a different population or formulation.

Microbes can participate in energy, glucose and lipid regulation through metabolites, bile acids and immune signals. This does not replace energy expenditure, glycogen stores or protein needs. A changed microbial pathway does not create free calories or guaranteed muscle growth. Adequate intake and appropriate training remain recovery foundations. Disease-treatment or metabolic-improvement claims also require a defined human outcome rather than a mechanistic possibility alone.