From boron symbiotaxis to symbiogenic nutrients: extending the concept of ecological essentiality.

Nutritional science has traditionally interpreted the biological functions of nutrients according to their metabolic roles within the host organism. Microbiome-oriented concepts, including prebiotics, probiotics, synbiotics, and postbiotics, have substantially expanded this perspective by recognizing the biological importance of microbial communities. However, existing nutritional classifications remain largely centered on either the host or the microbiota, without explicitly considering the functional organization emerging from their continuous interaction. In this review, we propose the concept of symbiogenic nutrients (SNs) as a complementary functional classification of nutrients defined according to their demonstrated capacity to preserve, restore, or enhance host-microbiome functional organization (HMFO). Building upon the concepts of ecological essentiality and boron (B) symbiotaxis, we introduce a systems-oriented framework in which nutritional function is interpreted not only through direct metabolic activities or microbial modulation but also through preservation of the structural, communicative, ecological, and metabolic processes that collectively sustain functional symbiosis. To facilitate operational implementation, we propose explicit principles and criteria for the classification of SNs and illustrate their application using B as the first experimentally supported prototype. Current evidence indicates that B contributes to biological interface integrity, microbial communication, ecological regulation, and host metabolic integration, thereby fulfilling the proposed operational framework. The concept is further extended from individual SNs to symbiogenic compositions, interface-active compositions, and symbiogenic nutrition, as a systems-oriented nutritional strategy aimed at preserving HMFO. This framework provides new perspectives for healthy longevity, metabolic health, chronic inflammation, and precision nutrition, establishing a conceptual foundation for future interface-targeted nutritional interventions.