In the current landscape of evidence-based medicine, functional fibers have become increasingly integrated as solid evidence in promoting health. Medical scientists have succeeded in a new stage of growing endophytic filamentous fungi within cotton fibers as new avenues to manufacture biocontrol agents. Others have accelerated research to develop functionalized yeast capable of highly efficient and sustainable biopolymer production. This guide attempts to address the various gaps and synthesizes the current level of knowledge on novel health-promoting functional fibers and the construction of next-generation biopolymers. Through this fusion, the readers will appreciate how fibers have evolved as core components in modern medicine and in addressing the world’s various problems.<\/p>\n\n\n\n