Streptococcus Thermophilus Y08
Also known as: S. thermophilus, Streptococcus thermophilus Y08, Streptococcus thermophilus
Overview
Streptococcus thermophilus is a thermophilic lactic acid bacterium widely utilized as a starter culture in the production of fermented dairy products like yogurt and cheese. It is naturally found in these fermented milk products. While considered a probiotic candidate due to its potential gut health benefits, its probiotic status is subject to debate. This is primarily due to variable survival rates in the human gastrointestinal tract (GIT) and taxonomic confusion with closely related species such as S. salivarius. Research on S. thermophilus is of moderate maturity, with numerous strain-specific studies available. However, systematic reviews often highlight inconsistent evidence regarding its overall probiotic effects and survival in humans. The quality of evidence varies, with some studies lacking rigorous strain identification or adequate controls. Nevertheless, genomic analyses of tested strains consistently confirm their safety, indicating the absence of pathogenicity or antibiotic resistance genes.
Benefits
Streptococcus thermophilus shows promising primary effects, particularly in reducing the incidence of antibiotic-associated diarrhea (AAD). One randomized controlled trial (RCT) demonstrated that yogurt containing S. thermophilus significantly reduced AAD rates from 23.7% to 12.4% in adults undergoing antibiotic treatment. This suggests a clinically significant benefit for this specific population. Additionally, in animal models, S. thermophilus has shown potential to improve intestinal tissue health in cases of chemotherapy-induced mucositis. Secondary effects observed in model organisms, such as the extension of lifespan in Caenorhabditis elegans through the upregulation of antioxidant genes, suggest potential anti-aging properties, though these findings are not directly translatable to humans. While primarily studied in adults receiving antibiotics or chemotherapy, evidence for its efficacy in functional gastrointestinal disorders (FGIDs) remains inconclusive, with some RCTs reporting no significant improvements in quality of life. The strength of evidence for AAD reduction is high, while other benefits require further validation through large-scale RCTs.
How it works
Streptococcus thermophilus primarily exerts its effects by producing lactic acid through fermentation. This process contributes to maintaining a balanced gut microbiota and lowers the intestinal pH, which can inhibit the growth of harmful pathogens. Certain strains of S. thermophilus are also known to produce gamma-aminobutyric acid (GABA), a neurotransmitter that may enhance the bacterium's acid tolerance and potentially exert neuromodulatory effects. Furthermore, S. thermophilus may modulate host antioxidant gene expression, as observed with the upregulation of the daf-16 gene in nematodes, suggesting a role in reducing oxidative stress. However, its survival through the human gastrointestinal tract is highly strain-dependent and often transient, which can impact its overall probiotic efficacy.
Side effects
Streptococcus thermophilus is generally considered safe for human consumption. Genomic analyses of various strains have consistently shown the absence of antibiotic resistance genes or virulence factors, reinforcing its safety profile. In clinical studies, S. thermophilus is typically well-tolerated, with no significant adverse effects commonly reported. There are no known significant drug interactions associated with S. thermophilus; however, its effectiveness as a probiotic during antibiotic use may depend on the timing of administration and the viability of the specific strain. While no specific contraindications for S. thermophilus have been documented, immunocompromised individuals should exercise caution when using any probiotic supplement and consult with a healthcare professional. Overall, the risk of adverse events with S. thermophilus is very low, making it a safe option for most individuals.
Dosage
There is no universally standardized dosage specifically established for Streptococcus thermophilus Y08 or other S. thermophilus strains. However, typical probiotic doses, especially when delivered through fermented products, generally range from 10^8 to 10^10 colony-forming units (CFU) per day. The optimal dosage can vary significantly depending on the specific strain's viability and the product's formulation. Higher doses might improve gut colonization, but this requires further confirmation through dedicated clinical trials. For the prevention of antibiotic-associated diarrhea (AAD), it is recommended to administer S. thermophilus concurrently with antibiotic treatment. S. thermophilus is most commonly consumed via yogurt or other fermented milk products. Encapsulated forms may offer improved survival through the gastrointestinal tract, potentially enhancing efficacy. There are no established upper limits or safety thresholds that have been identified as problematic for S. thermophilus.
FAQs
Is S. thermophilus Y08 a confirmed probiotic?
Evidence supports some probiotic effects, particularly for specific strains, but its survival and efficacy in the human gut are highly strain-specific and often transient, meaning it may not colonize long-term.
Is it safe during antibiotic treatment?
Yes, S. thermophilus is generally considered safe during antibiotic treatment. It may help reduce the incidence of antibiotic-associated diarrhea when consumed concurrently with antibiotics.
How long before benefits appear?
Benefits like the reduction of antibiotic-associated diarrhea typically occur during the course of antibiotic treatment. Other potential effects may require longer or are not yet well-established in human studies.
Can it colonize the gut?
Colonization of the gut by S. thermophilus is generally transient and varies significantly by strain. It often does not establish a permanent presence in the intestinal microbiota.
Research Sources
- https://pmc.ncbi.nlm.nih.gov/articles/PMC7468695/ – This review highlights the inconsistent survival of Streptococcus thermophilus in the human gastrointestinal tract and discusses issues related to taxonomic misidentification in various studies. It emphasizes the need for more rigorous strain-level identification in probiotic research.
- https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2020.00184/full – This genomic analysis of four Streptococcus thermophilus strains from fermented milk confirmed their safety, showing no antibiotic resistance or pathogenic genes. It also identified the production of gamma-aminobutyric acid (GABA) in some of the analyzed strains, suggesting potential functional properties.
- https://pmc.ncbi.nlm.nih.gov/articles/PMC11450280/ – This systematic review, which included an RCT by Gomi et al. (2018), found no significant improvement in quality of life for patients with functional gastrointestinal disorders (FGIDs) when using Streptococcus thermophilus YIT 2021. The findings suggest limited efficacy for this specific strain in FGID management.
- https://en.wikipedia.org/wiki/Streptococcus_thermophilus – This Wikipedia entry provides a general overview of Streptococcus thermophilus, including its use in dairy fermentation and its potential probiotic properties. It references a clinical trial demonstrating that yogurt containing S. thermophilus reduced the incidence of antibiotic-associated diarrhea from 23.7% to 12.4%.
- https://www.webmd.com/vitamins/ai/ingredientmono-1621/streptococcus-thermophilus – This WebMD article provides a general summary of Streptococcus thermophilus, outlining its common uses, potential benefits, and safety profile. It serves as a consumer-oriented resource for understanding this probiotic candidate.