Traditional probiotics represent the first generation of probiotic development, characterized by live microorganisms with a long history of safe use in foods and supplements. Dominated by Lactobacillus and Bifidobacterium species, these strains are widely recognized for supporting digestive balance, immune function, and skin health. Despite extensive clinical testing, traditional probiotics are generally positioned for maintenance of health rather than targeted medical intervention, highlighting both their strengths and limitations. This has driven increasing interest in next-generation probiotics and postbiotics while maintaining traditional probiotics as a trusted, regulatory-friendly baseline in the global market.