Abstract: - The purpose of this review is to investigate the health benefits of probiotics, which are live bacteria that favorably affect people when consumed in enough amounts. Probiotics such as yeast, bifidobacteria, and lactic acid bacteria are commonly utilized. As mentioned in this review, these beneficial bacteria may compete with pathogens that alter the gut microbiota and have anti-obesity, anti-diabetic, anti-cancer, and immunomodulatory properties. A number of medications, including antibiotics, can now be replaced with probiotics. A period of major changes is hinted at by the growth of fields devoted to the study of the microbiome and the role that probiotics play in enhancing it. An increasing number of potential probiotic species are being discovered that can target newly identified host targets and microbial niches based on data. In order to protect human health, probiotics, symbiotics, postbiotics, microbial consortia, live biotherapeutic products, and genetically modified organisms are among the new types of microbiome-modulating interventions under development. Polyphenols, fibers, and fermented foods are also receiving more attention. The effectiveness of probiotics is also influenced by the delivery system because the agents used in the delivery aid the bacteria in surviving in the hostile environment of the human gut.