L. crispatus probiotics have shown promise for the prevention of urinary and genital infections in women, but the research is still in its very early stages. What have scientists discovered? Read on to find out.
What is Lactobacillus crispatus?
Lactobacilli inhabiting the human vagina are the first line of defense in the female urogenital and reproductive tracts. Lactobacillus crispatus is prevalent in the healthy cervicovaginal microbiota, where it produces lactic acid, a potent broad-spectrum bactericide, and virucide, and acts as an immunomodulatory agent [1].
Health Benefits of L. crispatus
L. crispatus probiotic supplements have not been approved by the FDA for medical use and generally lack solid clinical research. Regulations set manufacturing standards for them but don’t guarantee that they’re safe or effective. Speak with your doctor before supplementing.
Insufficient Evidence For
The following purported benefits are only supported by limited, low-quality clinical studies. There is insufficient evidence to support the use of L. crispatus probiotics for any of the below-listed uses. Remember to speak with a doctor before taking L. crispatus, and never use it in place of something your doctor recommends or prescribes.
1) Female Urogenital Health
L. crispatus reduced recurrent urinary tract infections in 100 premenopausal women [2].
L. crispatus inhibited Chlamydia trachomatis, the most common sexually transmitted bacterial pathogen, in human epithelial cells and macrophages [3, 4].
L. crispatus promoted defense against Candida albicans infection in cell studies [5, 6].
L. crispatus inhibited E. coli activity [7].
Cervicovaginal mucus with high L. crispatus concentrations trapped the HIV virus in a lab setting. It is unclear whether this result has any relevance to HIV infection in a clinical setting, and we recommend strongly against attempting to use L. crispatus to prevent HIV [8].
Animal & Cell Research (Lacking Evidence)
No clinical evidence supports the use of L. crispatus for any of the conditions listed in this section. Below is a summary of the existing animal and cell-based research, which should guide further investigational efforts. However, the studies listed below should not be interpreted as supportive of any health benefit.
2) Allergies
Oral ingestion of L. crispatus alleviated allergic rhinitis in mice, possibly via the adjustment of the Th1/Th2 balance [9, 10, 11].
3) Gut Health
L. crispatus ameliorated colitis in mice [12], however, a specific strain, M206119, exacerbated intestinal inflammation [13].
Cancer Research
L. crispatus inhibits the proliferation of breast cancer cells [14], human cervical cancer cells, and colon adenocarcinoma cells [15].
These cell studies should not be used to draw conclusions about L. crispatus against cancer in either animals or humans. They simply indicate that further studies are justified.
Mechanism of Effect
In cells and animals, researchers have observed that L. crispatus:
- Increased [16, 17] and decreased IL-6 [3].
- Decreased IL-8 [3, 5, 16] and IL-4 [9].
- Increased IL-10 [3, 18] and IL-12p70 [18].
- Decreased TNF-α [3].
- Induced NF-κB activation [16].
- Increased IgA [17] and decreased IgE [9].
- Increased CD4(+) CD25(+) FOXP3(+) Treg cells [18].
Safety
L. crispatus was shown to be safe in women treated for bacterial vaginosis [19, 20]. Mild inflammation of the urinary tract was noted in some women [21].
L. crispatus probiotics are generally considered safe. However, to avoid adverse effects or unexpected interactions, talk to your doctor before using L. crispatus.
