What is Lactobacillus plantarum?
Lactobacillus plantarum (now officially classified as Lactiplantibacillus plantarum) is a hardy, versatile lactic acid bacterium found in many fermented foods such as sauerkraut, kimchi, pickles and sourdough. It tolerates stomach acid relatively well, which is one reason it is popular in supplements.
Like other lactobacilli, it produces lactic acid, which helps keep the vaginal environment mildly acidic. A healthy vaginal microbiome in women of reproductive age is usually dominated by one or a few Lactobacillus species, and loss of that dominance is linked to bacterial vaginosis and, in some studies, to a higher risk of urinary tract infections. That background is why lactobacilli appear in so many women’s wellness formulas.
What the research says
Most of the human research on L. plantarum concerns digestive outcomes, especially specific strains such as 299v studied in irritable bowel syndrome. Evidence for urinary or vaginal outcomes is thinner. Small studies have tested particular strains for urinary tract infections in children and for vaginal health in women, but these used different strains and settings, and the overall picture for probiotics in UTI prevention, summarized in a 2015 Cochrane review, did not show a significant benefit.
For urinary health in general, the evidence for probiotics is weaker than marketing suggests. A 2015 Cochrane review of nine trials found no significant reduction in recurrent symptomatic UTIs with probiotics compared with placebo, and noted that most studies were small with a high risk of bias. For bacterial vaginosis, a 2022 meta-analysis of randomized trials found that adding probiotics to antibiotic treatment modestly improved cure rates, but the products, strains and routes (oral versus vaginal) varied widely.
A key point, emphasized by the NCCIH and by a large 2018 systematic review of strain specificity, is that results from one strain cannot be assumed to apply to another strain of the same species. A study of one commercial strain says little about a different strain with a different code on the label.
How it’s used in supplements
The strain in FemiCore, Lp05, is a commercial strain. We did not find published clinical trials of Lp05 for bladder control, urinary leakage or UTI prevention.
Probiotic doses are measured in colony forming units (CFU), typically ranging from about 1 billion to tens of billions per day in research. A label that lists strains only in milligrams, especially inside a combined blend, does not tell you how many live organisms you are getting or whether they survive to the end of shelf life. Look for products that state CFU at expiration, name the exact strain, and ideally cite trials of that strain.
Probiotics are generally well tolerated in healthy people. Mild gas or bloating in the first days is common. People who are seriously ill or have weakened immune systems face a small risk of serious infection and should talk to a doctor before using them.
Safety and cautions
Generally well tolerated; mild gas or bloating can occur at first. People with weakened immune systems, serious illness, central venous catheters or recent surgery should talk to a doctor first because of a small risk of serious infection. Product quality varies and some probiotic products have been found to contain organisms not listed on the label. Do not use a probiotic in place of medical care for a suspected infection.
Supplements we reviewed that contain it
★★★☆☆
FemiCore reviewFemiCore is a once-daily capsule combining cranberry, bearberry, berberine, mimosa pudica and five lactobacillus strains, marketed for bladd...
