How much probiotics is too much
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Understanding the Optimal Dosage of Probiotics: How Much is Too Much?
Probiotic Dosage and Health Benefits
Definition and Adequate Amounts
Probiotics are defined as live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. However, the term "adequate amounts" is not precisely defined, leading to varying interpretations and applications in both research and clinical settings .
Dose-Response Relationships in Probiotics
Simulated Gastro-Intestinal Passage
Research has shown that the recovery and metabolic output of probiotic strains can vary significantly with different doses. In a study simulating upper gastro-intestinal passage and colonic fermentation, two doses of a probiotic mixture (7 × 10^9 CFU and 7 × 10^10 CFU) were tested. The higher dose resulted in a greater detection of all four strains tested (Bifidobacterium lactis Bl-04, Lactobacillus acidophilus La-14, Lactobacillus paracasei Lpc-37, and Lactobacillus plantarum Lp-115), as well as increased production of propionic acid and total short-chain fatty acids (SCFA). This suggests that higher doses may be necessary to achieve measurable increases in probiotic levels and their metabolic byproducts.
Human Studies and Meta-Analyses
A comprehensive review of human studies and meta-analyses reveals mixed results regarding the dose-response relationship of probiotics. For antibiotic-associated diarrhea (AAD), a positive dose-response effect was observed, indicating that higher doses of probiotics are more effective in reducing the risk of AAD. However, for other conditions such as Clostridium difficile-associated diarrhea, necrotizing enterocolitis, atopic dermatitis prevention, and slow intestinal transit, no clear dose-response relationship was identified.
Specific Strains and Conditions
Blood Pressure and Acute Gastroenteritis
Higher doses of probiotics (greater than 10^11 CFU) have been found to be more effective in reducing blood pressure, according to a meta-analysis. Additionally, for the treatment of acute gastroenteritis in children, a specific strain, Lactobacillus rhamnosus GG, showed a breakpoint for effectiveness, although no dose-response was observed for other probiotics assessed.
General Health and Immune Markers
For other health endpoints such as immune markers, general health, and bowel function, studies did not exhibit clear dose-response relationships. This indicates that while higher doses may be beneficial for certain conditions, they do not universally translate to better outcomes across all health parameters.
Conclusion
Determining the optimal dosage of probiotics is complex and varies depending on the specific health condition and probiotic strain. While higher doses may be beneficial for conditions like antibiotic-associated diarrhea and blood pressure reduction, they do not necessarily offer additional benefits for other health endpoints. More research is needed to establish clear guidelines for the adequate amounts of probiotics required to achieve specific health benefits.
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