<p>Probiotics are live beneficial microorganisms that confer health benefits to the host when administered in adequate amounts, have gained considerable scientific and commercial interest for their ability to support gut health, strengthen immunity, and reduce disease risk. This review traces the genesis of probiotic science from its origins in traditional fermented foods to contemporary clinical applications, offering a conceptual understanding of its evolution. A clear distinction is drawn between endogenous probiotics, naturally resident in the human microbiome, and exogenous probiotics, introduced via dietary supplements and functional foods. The broad spectrum of documented health benefits is examined, encompassing digestive, immune, metabolic, neurological, and dermatological outcomes. Recent innovations are highlighted, including bioengineered probiotic strains with targeted therapeutic functions, the integration of probiotics with prebiotics as synbiotics, and advanced delivery systems such as microencapsulation and nanotechnology. Special attention is given to regulatory frameworks, with global comparisons and a focused case study on Argentina, alongside a structured roadmap for translating research into market-ready products. The review also addresses inclusivity in probiotic use, emphasizing safety considerations across diverse populations, and underscores the strain-specific nature of probiotic effects. Current challenges such as commercialization gaps, regulatory inconsistencies, and underexplored applications in non-digestive health domains are critically discussed. The conclusion calls for interdisciplinary collaboration among microbiologists, nutritionists, clinicians, and technologists to accelerate innovation, ensure equitable access, and maximize the potential of probiotics in promoting health and preventing disease.</p>