Can probiotics make you sick
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Can Probiotics Make You Sick?
Introduction to Probiotics and Their Benefits
Probiotics are live microorganisms that, when administered in adequate amounts, confer health benefits to the host, particularly in the gastrointestinal tract. They have been widely studied for their potential to improve gut health, modulate the immune system, and even influence brain function through the microbiota-gut-brain axis3 5 7. However, despite their benefits, there are concerns about the safety and potential adverse effects of probiotics.
Potential Adverse Effects of Probiotics
Infections and Immune Reactions
Probiotics, being live microorganisms, can theoretically cause infections, especially in susceptible individuals. These infections are rare and have primarily been observed in critically ill patients, those with compromised immune systems, and hospitalized individuals1 2 6. The main adverse effects reported include sepsis, fungemia, and gastrointestinal ischemia2. These risks highlight the importance of considering the health status of individuals before recommending probiotics.
Gastrointestinal Side Effects
Probiotics can also cause gastrointestinal side effects such as bloating, gas, abdominal pain, and diarrhea, particularly when consumed in large doses. These side effects are generally mild and depend on individual sensitivity and the presence of conditions like irritable bowel syndrome or gastroesophageal reflux1. Prebiotics, which are often combined with probiotics, can exacerbate these symptoms due to their osmotic effects and fermentation in the colon1.
Antibiotic Resistance
Another concern is the potential for probiotics to contribute to the spread of antibiotic resistance. The gastrointestinal tract can act as a reservoir for antibiotic resistance genes, which can be transferred between probiotics, normal microbiota, and opportunistic pathogens through horizontal gene transfer. This poses a significant risk, especially in the context of the global antibiotic resistance crisis9.
Safety in Specific Populations
Critically Ill and Immunocompromised Patients
The safety of probiotics is particularly concerning in critically ill and immunocompromised patients. Studies have shown that these populations are at a higher risk of adverse effects, including severe infections2 4. Therefore, the use of probiotics in these groups should be carefully evaluated, and the risk-benefit ratio should be thoroughly considered before administration.
General Population
For the general population, probiotics are generally considered safe. The long history of probiotic use and data from clinical trials support their safety for most people6. However, it is essential to monitor for any adverse effects and adjust the dosage or discontinue use if necessary.
Conclusion
While probiotics offer numerous health benefits, they are not without risks. Infections, gastrointestinal side effects, and the potential spread of antibiotic resistance are significant concerns, particularly for vulnerable populations. Therefore, it is crucial to consider individual health conditions and consult healthcare professionals before starting probiotic therapy. Further research is needed to better understand the safety profile of probiotics and to develop guidelines for their safe use.
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Most relevant research papers on this topic
Tolerance of probiotics and prebiotics.
Probiotics and prebiotics show clinical efficacy, but their side effects depend on dose and individual sensitivity factors, with tolerance likely being an adaptation to chronic consumption.
Literature Review
Highly CitedA systematic review of the safety of probiotics
Probiotics are generally safe, but their use in critically ill patients and those with immune-compromised complexity requires careful consideration of their risk-benefit ratio.
Systematic ReviewHighly CitedProbiotics Improve Inflammation-Associated Sickness Behavior by Altering Communication between the Peripheral Immune System and the Brain
Probiotics can improve inflammation-associated sickness behaviors by altering immune system communication with the brain, potentially offering new therapeutic alternatives for patients with systemic inflammatory diseases.
Non-RCT
Animal Study
Very Rigorous JournalHighly CitedProbiotic and synbiotic therapy in critical illness: a systematic review and meta-analysis
Probiotics show promise in reducing infections, including ventilator-associated pneumonia, in critical illness, but more high-quality clinical trials are needed to confirm these benefits.
Meta-Analysis
Rigorous JournalHighly CitedProbiotics and immunity
Probiotics can provide health benefits by modulating immune functions, potentially protecting against colitis, allergen sensitization, asthma, and allergic rhinitis.
Rigorous JournalHighly CitedRisk and safety of probiotics.
Probiotics are generally safe for most populations, but more research is needed to properly describe the incidence and severity of adverse events related to probiotics.
Highly CitedProbiotics in Autoimmune and Inflammatory Disorders
Probiotics may improve gastrointestinal symptoms and multiorgan inflammation in autoimmune disorders like rheumatoid arthritis, ulcerative colitis, and multiple sclerosis.
Very Rigorous JournalHighly CitedProbiotics in Disease Prevention and Treatment
Probiotics show strong evidence in preventing or treating 5 disorders, with potential benefits from inhibition of bacterial adhesion, enhanced mucosal barrier function, immune modulation, and neuroregulation.
Meta-AnalysisVery Rigorous JournalHighly CitedAntibiotic resistance propagation through probiotics
Probiotics may contribute to antibiotic resistance by transferring resistance genes among pathogens, probiotics, and gut microbiota in the gastrointestinal tract, potentially impacting personalized medicine and gene therapy.
Systematic ReviewProbiotics for preventing acute upper respiratory tract infections
Probiotics may help prevent acute upper respiratory tract infections in people of all ages, with minor side effects and gastrointestinal symptoms being the most common.
Meta-AnalysisVery Rigorous JournalHighly Cited