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Lactobacillus plantarum W1

Also known as: Lactobacillus plantarum, Lactiplantibacillus plantarum, L. plantarum, Lactobacillus plantarum W1

Overview

*Lactobacillus plantarum* is a Gram-positive, facultative anaerobic bacterium widely found in fermented foods, dairy products, and the human gastrointestinal tract. As a probiotic supplement, it is used to support gut health, modulate immunity, and potentially reduce obesity and inflammation. This bacterium is highly adaptable, produces antimicrobial compounds, and is generally regarded as safe for human consumption. While research on the species and some strains is robust, direct evidence for the W1 strain is limited. Studies suggest *L. plantarum* can reduce body weight and BMI, modulate inflammatory cytokines, and improve symptoms of irritable bowel syndrome (IBS). It exerts its effects primarily within the gut, influencing the gut microbiota composition and immune responses.

Benefits

*Lactobacillus plantarum* supplementation has shown several evidence-based benefits. A 2024 meta-analysis indicated significant reductions in body weight and BMI compared to placebo. Meta-analyses also suggest that *L. plantarum* can decrease pro-inflammatory cytokines like IL-4 and modulate host immunity. Specific strains have demonstrated weight loss in clinical trials. Furthermore, it improves symptoms in individuals with irritable bowel syndrome (IBS), with clinically meaningful reductions in symptom scores. These benefits are primarily observed in adults with obesity and individuals with IBS. The effects on weight/BMI are typically seen over 8–12 weeks, while cytokine changes can be detected within weeks.

How it works

*Lactobacillus plantarum* exerts its effects through several biological pathways. It modulates the gut microbiota by enhancing beneficial bacteria, inhibiting pathogens, and strengthening gut barrier function. It also modulates the immune system by reducing pro-inflammatory cytokines (e.g., IL-4, TNF-α) and increasing anti-inflammatory cytokines (e.g., IL-10). Additionally, it may influence energy metabolism and fat storage through the gut-brain axis and microbial metabolite production. *L. plantarum* primarily interacts with the gastrointestinal and immune systems, exerting its effects locally in the gut and through microbial metabolites.

Side effects

*Lactobacillus plantarum* is generally recognized as safe (GRAS) for most populations. Common side effects are rare, but mild gastrointestinal symptoms such as bloating and gas may occur in sensitive individuals. Uncommon and rare side effects are very rare, with no significant adverse events reported in large trials or meta-analyses. No significant drug interactions have been reported, although there is a theoretical risk with immunosuppressants. There are no established contraindications for healthy adults, but caution is advised in severely immunocompromised individuals. While safe for most adults, there is limited data in children, pregnant, or lactating women.

Dosage

The minimum effective dose of *Lactobacillus plantarum* is 1–5 billion CFU/day for general gut health. Higher doses, up to 10–50 billion CFU/day, have been used in clinical trials for specific conditions. The optimal dosage range is 5–50 billion CFU/day, depending on the indication and strain. Up to 100 billion CFU/day has been used in research without significant adverse effects, but long-term safety data are limited. It is best taken with food to enhance survival through the stomach. Capsules or powders are common forms, and it is important to ensure strain viability and proper storage. *L. plantarum* is not absorbed systemically, exerting local gut effects.

FAQs

Is *Lactobacillus plantarum* safe?

Yes, it is generally safe, but mild gastrointestinal symptoms are possible. Consult a healthcare provider if you have concerns.

When should I take *Lactobacillus plantarum*?

Take it with food for best results. Consistency is key for optimal benefits.

What results can I expect from taking *Lactobacillus plantarum*?

Expect modest improvements in weight, BMI, gut health, and inflammation over 8–12 weeks. Results may vary.

Is *Lactobacillus plantarum* a cure-all?

No, it is not a cure-all. Benefits are modest and may vary by strain and individual. It should be part of a holistic approach.

Are there any risks associated with taking *Lactobacillus plantarum*?

For most people, *Lactobacillus plantarum* is safe. However, individuals with severely compromised immune systems should consult their healthcare provider before use.

Research Sources

https://pubmed.ncbi.nlm.nih.gov/39062848/ – This meta-analysis of nine RCTs found that *L. plantarum* supplementation significantly reduced body weight and BMI compared to placebo. The studies included in the meta-analysis typically had a duration of 8-12 weeks, suggesting that benefits are observed over this timeframe. The authors noted heterogeneity in strains and dosages as a limitation, and called for more long-term data.
https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2021.643420/full – This meta-analysis of RCTs found that *L. plantarum* reduced IL-4 levels, indicating immune modulation. The studies included in the analysis typically had a duration of 4-12 weeks. The authors noted that the analysis was limited to specific cytokines and that strain variability may play a role in the observed effects.
https://www.mdpi.com/2072-6643/17/7/1165 – This randomized controlled trial found that a specific strain of *L. plantarum* (LMT1-48) resulted in significant weight loss in the *L. plantarum* group. The study lasted for 12 weeks. The authors noted that the findings were limited to the single strain used in the study and may not be generalizable to other strains of *L. plantarum*.
https://www.e-dmj.org/journal/view.php?doi=10.4093%2Fdmj.2021.0370 – This study investigated the effects of *L. plantarum* on body fat. The results indicated significant weight loss in the *L. plantarum* group. The study utilized a randomized controlled trial methodology, enhancing the reliability of the findings.
https://www.wjgnet.com/1007-9327/full/v29/i28/4451.htm – This study examined the effect of *L. plantarum* on Irritable Bowel Syndrome (IBS) symptoms. The results showed clinically meaningful reductions in symptom scores in the *L. plantarum* group compared to placebo. The study highlights the potential of *L. plantarum* as a therapeutic intervention for managing IBS symptoms.