What type of microorganisms can modify bacteria within the gut?

Probiotics are live microorganisms that, when consumed in adequate amounts, confer health benefits to the host, particularly by modulating gut bacteria. They help maintain a balanced gut microbiota by increasing the population of beneficial bacteria, which can outcompete harmful bacteria, enhance digestion, and support immune function. The primary role of probiotics is to promote a healthy balance within the gut environment, thereby improving overall gut health and various aspects of metabolic function.

Other microorganisms such as pathogens, viruses, and fungi do not typically modify gut bacteria in a beneficial way. Pathogens can disrupt the gut microbiome and cause disease, viruses can infect gut cells and may not have a direct, positive role in modifying bacteria, and fungi can be opportunistic but do not primarily serve to maintain or enhance beneficial bacterial populations. Thus, probiotics distinctly serve the purpose of positively influencing the gut microbiota.