Vaginal pH dropped slightly (by 0.19 at 4 weeks). Nugent scores and lactobacilli levels did not change significantly.
Martoni 2022 · Source
Lactobacillus paracasei
Strain UALpc-04 (UAS Labs)
A versatile lactobacillus found in fermented dairy, the gut and sometimes the vagina, studied for vaginal bacteria, digestion, colds and allergies.
Versatilefound in dairy, the gut and sometimes the vagina
272healthy adults in a cold-season trial of a related strain
10strains in the Daily Probiotic blend
Why we love it
L. paracasei is a versatile lactobacillus that naturally lives in the gut. We included it to round out the lactobacilli in the blend, alongside species that are more at home in the vagina.
What does the research show?
Vaginal bacteria
In 23 healthy women, 4 weeks of oral strain LPC-S01 lowered Gardnerella levels in the vagina, and the strain itself reached the vagina in 2 women.
Vaginal pH
In 36 women taking an oral 10-strain capsule that included our strain, UALpc-04, vaginal pH dropped slightly over 4 weeks.
Colds and allergies
Strain 8700:2, paired with an L. plantarum strain, was linked with fewer colds in 272 healthy adults (55% vs 67% on placebo). Strain GM-080 eased sneezing in 122 children with year-round nasal allergies.
Bacterial vaginosis (BV)
In 13 women with BV without symptoms, an eight-strain oral capsule that included L. paracasei lowered some BV-linked bacteria over 2 months.
Studies
Human study tested in people Lab study a starting point, not proof
Studies that included our strain (UALpc-04)
Studies on other strains of this species
Gardnerella levels in the vagina went down. The strain itself was found in the vagina of 2 women.
Koirala 2020 · Source
55% caught at least one cold, compared with 67% on placebo.
Berggren 2011 · Source
Sneezing improved. Total nasal symptom scores did not differ from placebo.
Lin 2023 · Source
Some BV-linked bacteria fell. Lactobacilli rose but not significantly.
Filardo 2024 · Source
Gut bacteria and markers changed, but IBS symptoms did not improve more than placebo.
Cremon 2018 · Source
Which strain do we use?
Our strain is L. paracasei UALpc-04 (UAS Labs). It was one of 10 strains in a small oral blend study. The other studies on this page used other strains of this species, and results belong to the strain tested.
Is L. paracasei safe to take?
If you are immunocompromised, have a central line or a heart valve problem, or are critically ill, ask your clinician before taking probiotics. If you are pregnant or breastfeeding, ask your clinician first. Rare heart valve infections with L. paracasei have been reported, mostly in people with existing valve disease or dental problems. In the 10-strain study, two women had mild cramping or bloating that went away.
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
Last reviewed: November 2026.
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Reviewed by the Momotaro Apotheca medical team, including OB-GYNs and naturopathic doctors. Educational information, not medical advice. All ingredient research