Can probiotics cause yeast infections
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Can Probiotics Cause Yeast Infections?
Introduction to Probiotics and Yeast Infections
Probiotics are live microorganisms that provide health benefits when consumed in adequate amounts. They are commonly used to improve gut health and boost the immune system. However, there is a growing concern about whether probiotics, particularly those containing yeast, can cause yeast infections.
Probiotic Yeasts and Candida Infections
Inhibition of Candida Species by Probiotic Yeasts
Several studies have shown that probiotic yeasts can inhibit the virulence of Candida species, which are responsible for various infections. Probiotic yeasts such as Saccharomyces cerevisiae and Issatchenkia occidentalis have been found to prevent adhesion, morphological transition, and biofilm formation of Candida species, including Candida albicans, Candida tropicalis, Candida glabrata, Candida parapsilosis, and Candida auris 124. These yeasts use mechanisms like posing a physical barrier and secreting metabolites that inhibit Candida growth, making them a potential alternative or combination therapy for Candida infections 14.
Clinical Evidence of Probiotic Yeasts' Efficacy
Clinical studies have confirmed the in vitro and in vivo activity of probiotic yeasts against Candida species. For instance, in vivo studies using Caenorhabditis elegans infection assays have shown that probiotic yeasts protect the host from Candida infections 24. Additionally, a randomized controlled trial demonstrated that probiotic bacteria in cheese reduced the prevalence of oral Candida in the elderly, indicating the potential of probiotics in controlling yeast overgrowth .
Risks Associated with Probiotic Yeasts
Probiotic-Associated Fungemia
Despite the benefits, there are risks associated with the use of probiotic yeasts. Cases of fungemia, a bloodstream infection caused by fungi, have been reported in patients after the administration of probiotics containing Saccharomyces boulardii 35. These infections are particularly concerning in immunocompromised individuals, where the incidence might be underestimated .
Genetic Variability and Infection Risk
The genetic variability among Saccharomyces boulardii strains can influence their pathogenic potential. Studies have shown that even a single-gene loss-of-function mutation can increase the fitness of these yeasts in the host, leading to higher infection risks . Rapid identification methods have been developed to link clinical infections to probiotic strains, highlighting the need for careful monitoring and safety assessments .
Conclusion
While probiotic yeasts have shown promise in inhibiting Candida infections and reducing yeast overgrowth, they also pose risks, particularly in immunocompromised individuals. The potential for probiotic-associated fungemia and the genetic variability of probiotic strains necessitate cautious use and thorough safety evaluations. Further research is needed to fully understand the benefits and risks of probiotic yeasts in preventing and treating yeast infections.
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