What is a probiotic
Pro Research Analysisby 
Searched over 200M research papers
Understanding Probiotics: Definition, Mechanisms, and Health Benefits
Definition of Probiotics
Probiotics are defined as live microorganisms that, when administered in adequate amounts, confer a health benefit on the host2 3 7. These beneficial bacteria are often included in dietary supplements and functional foods, such as yogurt and other fermented products1 9. The most commonly used probiotic strains belong to the genera Lactobacillus and Bifidobacterium, among others7 8.
Mechanisms of Action
Gut Microbiota Modification
Probiotics work by modifying the gut microbiota, which is the community of microorganisms living in the intestines. They help maintain a healthy balance of gut bacteria, which is crucial for overall health2 4 5.
Competitive Adherence and Barrier Strengthening
Probiotics can adhere to the mucosa and epithelium of the gut, outcompeting harmful pathogens for space and resources. This competitive adherence helps to prevent infections and maintain the integrity of the gut epithelial barrier2 4.
Immune System Modulation
Probiotics also play a significant role in modulating the immune system. They interact with pattern recognition receptors like toll-like receptors, which help in modulating key signaling pathways. This interaction can enhance or suppress immune responses, providing a balanced antimicrobial response with minimal inflammatory damage2 5.
Production of Antimicrobial Substances
Probiotic bacteria produce various antimicrobial substances such as bacteriocins, lysozymes, and hydrogen peroxide, which inhibit the growth of harmful pathogens4 5.
Health Benefits
Gastrointestinal Health
Probiotics are widely recognized for their benefits in gastrointestinal health. They can alleviate conditions like lactose intolerance and reduce the risk of diarrhea, including rotavirus-induced diarrhea1 6. They are also effective in managing antibiotic-associated diarrhea and some inflammatory bowel disorders5.
Immune Enhancement
Probiotics have been shown to enhance immune functions. They can downregulate inflammatory cytokines and induce regulatory mechanisms, providing protection against conditions like colitis and allergic reactions3 5.
Potential in Disease Prevention
Emerging evidence suggests that probiotics may play a role in reducing the risk of certain cancers, such as colon cancer, and may also help in managing metabolic disorders like obesity and type 2 diabetes1 5 9. However, more research is needed to confirm these benefits.
Applications in Aquaculture
In aquaculture, probiotics are used to improve growth performance, disease resistance, and overall health of fish. They help in maintaining water quality and minimizing the side effects of antibiotics4.
Conclusion
Probiotics are live microorganisms that offer numerous health benefits, primarily through their effects on the gut microbiota and immune system. While they are most commonly used to improve gastrointestinal health, their potential applications extend to immune enhancement and disease prevention. Ongoing research continues to uncover new benefits and mechanisms of action, making probiotics a promising area of study in both human and animal health.
Sources and full results
Most relevant research papers on this topic
Prebiotics and probiotics: are they functional foods?
Probiotics and prebiotics, when combined, may provide health benefits and reduce disease risks, but further research is needed.
Highly CitedProbiotic Mechanisms of Action
Probiotics provide health benefits by altering gut microbiota, strengthening gut epithelial barrier, and modulating immune system, with potential therapeutic applications in various diseases.
Systematic ReviewHighly CitedProbiotics and immunity
Probiotics can provide health benefits by modulating immune functions, potentially protecting against colitis, allergen sensitization, asthma, and allergic rhinitis.
Rigorous JournalHighly CitedThe functionality of probiotics in aquaculture: An overview.
Probiotics in aquaculture improve growth performance, disease resistance, immunity, health status, gut microbiome, and water quality, while minimizing antibiotic side effects and boosting fish production and human health.
Literature ReviewHighly CitedMechanisms of Action of Probiotics.
Probiotics can prevent and treat various digestive disorders, allergic disorders, and metabolic disorders by colonizing and normalizing intestinal microbial communities, promoting immune system differentiation, and modulating endocrine and neurologic functions.
Very Rigorous JournalHighly CitedA successful history: probiotics and their potential as antimicrobials
Probiotics show potential as supportive therapy for certain clinical conditions, especially infectious diseases, despite some concerns about their safety and efficacy.
Systematic ReviewHighly CitedPotential Uses of Probiotics in Clinical Practice
Probiotics show potential in improving intestinal infections, reducing urogenital infections, and potentially managing cancer and allergies, but their widespread use requires further research and guidelines.
Highly CitedMicroorganisms with Claimed Probiotic Properties: An Overview of Recent Literature
Probiotics, especially those from Lactobacillus and Bifidobacterium genera, show health benefits for healthy individuals, but caution is needed for immunocompromised patients and those with leaky guts.
Literature ReviewHighly CitedProbiotics: how should they be defined?
Probiotics are microbial cell preparations or components of microbial cells that have a beneficial effect on the health and well-being of the host, excluding antibiotics.
Highly CitedProbiotics: potential pharmaceutical applications.
Probiotics can improve gut health, prevent diarrhea, and modulate immunity, potentially preventing cancer and lowering cholesterol levels.
Literature ReviewHighly Cited