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Limosilactobacillus reuteri ATCC PTA 6475 (BioGaia Osfortis®)

Limosilactobacillus reuteri ATCC PTA 6475 (formerly Lactobacillus reuteri ATCC PTA 6475)
Evidence Level
Limited
6 Clinical Trials
6 Documented Benefits
2/5 Evidence Score

Limosilactobacillus reuteri ATCC PTA 6475 is a single probiotic strain that BioGaia sells as Osfortis®, a capsule that also contains vitamin D (10 mcg, or 400 IU, per two capsules). It is a different strain from BioGaia Protectis (DSM 17938). The trials tested the strain, not Osfortis itself. In 90 women aged 75 to 80 with low bone density, the strain given alone, without vitamin D, slowed 12-month loss of volumetric bone density at the shin versus placebo, but hip and spine density did not differ significantly. In a larger 2-year trial in 239 women in early menopause, capsules with the same daily strain and vitamin D amounts as Osfortis did no better than a vitamin D placebo: bone loss, the main outcome, did not differ. A trial in older men found no change in testosterone. BioGaia funded or co-funded most of these trials.

Studied Dose 10 billion CFU a day (5 billion twice daily): 12 months, no vitamin D, in older women; 2 years with 400 IU vitamin D a day in every group, placebo included, in early postmenopausal women (1 billion CFU a day also tested). Osfortis label: 10 billion CFU plus 10 mcg (400 IU) vitamin D per 2 capsules.
Active Compound Live Limosilactobacillus reuteri ATCC PTA 6475 (freeze-dried); Osfortis capsules also contain vitamin D3 (10 mcg per 2 capsules), which the trials either left out (12-month bone trial) or gave to the placebo group too.

Benefits

Bone density in women aged 75 to 80, not in early menopause

In 90 women aged 75 to 80 with low bone density, 10 billion CFU a day of the strain alone, without vitamin D, cut 12-month loss of shin volumetric bone density to 0.83% versus 1.85% with placebo; hip and spine density did not differ significantly. In 239 women aged 50 to 60, neither dose, given with vitamin D, slowed bone loss over 2 years compared with a vitamin D placebo.

Supported by Trial 1, Trial 2

Bone turnover markers during a short prednisolone course

In 50 healthy adults aged 18 to 45, 10 billion CFU a day, with vitamin D in both arms, for 2 weeks before and during a 7-day course of prednisolone 25 mg did not change the bone turnover markers CTX, PINP or osteocalcin compared with placebo, and glucose on continuous monitoring did not differ. This drug-exposure test does not show a bone benefit.

Supported by Trial 3, Trial 2

Gut barrier and digestive comfort in a 6-week trial

In 65 adults with diarrhea-predominant irritable bowel syndrome, 1 billion CFU a day of the single strain did not change small or large intestinal permeability versus placebo. Symptom scores improved at 3 weeks but not significantly for the single strain, no symptom differed from placebo at 6 weeks, and blood IL-6 tended to fall (p = 0.052).

Supported by Trial 4

Testosterone levels in healthy men aged 55 to 65

In a 12-week placebo-controlled trial in 57 men, 1 or 10 billion CFU a day, in capsules with vitamin D that the placebo also contained, did not change testosterone. As a secondary finding, triglycerides fell in the high-dose group (1.54 to 1.20 mmol/L) and differed from placebo. A 10-person open-label study in Japan without a placebo group also saw no notable change in sex hormones.

Supported by Trial 5, Trial 6

Two-strain L. reuteri blend with DSM 17938 for digestive comfort

This evidence is for blends of this strain with DSM 17938, not the strain alone. In 140 adults with irritable bowel syndrome, the blend twice daily for 14 weeks with usual care eased symptom scores versus placebo from week 6 and lowered fecal calprotectin. In a separate 6-week trial, the blend's symptom gain at 3 weeks was gone by week 6.

Supported by Trial 4

Bone and testosterone findings in animal and lab studies

This is animal and lab work, not human evidence. The strain protected ovariectomized mice from bone loss and lowered markers of bone breakdown, and it slowed formation of bone-resorbing cells in lab dishes. Aging male mice given it in drinking water kept higher testosterone and larger testes; a human trial did not confirm a testosterone effect.

Supported by Trial 3

Mechanism of action

1

Suppression of bone-resorbing osteoclasts

In ovariectomized mice the strain lowered the osteoclast markers Trap5 and RANKL and reduced bone marrow CD4+ T cells, which promote osteoclast formation. In lab cultures, the strain's conditioned supernatant and lactobacillic acid, a fatty acid it makes, blocked osteoclast development and lowered NF-kB and p38 signaling, partly through the GPR120 receptor.

2

Gut microbiota and inflammatory state in older women

In a secondary analysis of 20 women from the 12-month bone trial, those whose bone density responded best had higher gut bacterial gene richness and a better inflammatory profile than poor responders, and less E. coli enrichment. This compared responders within the probiotic group, not probiotic with placebo.

3

Shifts in blood metabolites

In a post hoc analysis of the 12-month bone trial, blood metabolite profiles separated the probiotic and placebo groups, and butyrylcarnitine was higher at every time point on the probiotic, which the authors linked to butyrate signaling. No single metabolite stayed significant after correction for multiple testing.

Clinical trials

1
12 months in women aged 75 to 80 with low bone density
PubMed

Randomized, double-blind, placebo-controlled trial of L. reuteri ATCC PTA 6475, 10 billion CFU a day as a powder in stick packs with no vitamin D (placebo was maltodextrin), for 12 months; primary outcome was relative change in tibia total volumetric BMD; funded by BioGaia AB, the Swedish Research Council and Sahlgrenska University Hospital; NCT02422082. (Nilsson et al. 2018, J Intern Med)

90 women aged 75 to 80 with a DXA T-score of -1 or lower at the spine or hip, osteoporosis excluded; 70 completed.

Tibia total volumetric BMD fell 0.83% with L. reuteri versus 1.85% with placebo in the intention-to-treat analysis (mean difference 1.02%, 95% CI 0.02 to 2.03). The secondary bone outcomes, including hip and spine areal BMD, showed similar but smaller effects that were not statistically significant in the intention-to-treat population; trabecular bone volume fraction was significant only in per-protocol and sensitivity analyses. Adverse events did not differ between groups.

2
2 years in early postmenopausal women: no effect
PubMed

Randomized, double-blind, placebo-controlled single-center trial in Sweden of 1 or 10 billion CFU a day (0.5 or 5 billion CFU twice daily) for 2 years, a bone trial whose primary outcome was tibia total volumetric bone mineral density (vBMD); all capsules, placebo included, had 200 IU vitamin D3 (400 IU a day), so the high dose matched the Osfortis daily formula and was compared with vitamin D alone; funded by BioGaia AB, the Swedish Research Council and Sahlgrenska University Hospital, with randomization done by BioGaia; NCT04169789. (Gregori et al. 2024, JAMA Netw Open)

239 women aged 50 to 60 (median 55) in early menopause (80 high dose, 80 low dose, 79 placebo).

The primary outcome was null: tibia total vBMD fell in all groups with no difference from placebo for either dose. Hip and spine vBMD, the turnover markers CTX and PINP, and other predefined outcomes also did not differ. A prespecified analysis found an interaction between body mass index and treatment at 2 years. No treatment-related serious adverse events occurred.

3
Prednisolone course in healthy adults: no difference from placebo
PubMed

Randomized, double-blind, placebo-controlled proof-of-concept trial of L. reuteri ATCC PTA 6475 on bone turnover markers: 10 billion CFU a day (5 billion CFU twice daily, with 200 IU vitamin D3 per capsule in both arms) for 2 weeks, then open-label prednisolone 25 mg a day for 7 days; funded by the Swedish Research Council, Sahlgrenska grants and BioGaia AB; NCT04767711. (Gregori et al. 2025, JBMR Plus)

50 healthy adults aged 18 to 45 (21 men, 29 women); 46 completed.

The primary outcomes were null: changes in CTX (p = 0.98), PINP (p = 0.43) and osteocalcin (p = 0.21) did not differ between probiotic and placebo. Mean blood glucose on continuous monitoring did not differ either (p = 0.28). The authors call for larger studies to find any smaller effect.

4
Gut barrier and symptoms over 6 weeks
PubMed

Exploratory randomized placebo-controlled three-arm trial: ATCC PTA 6475 alone (at least 1 billion CFU a day) or with DSM 17938, versus placebo, for 6 weeks; two authors are BioGaia employees and BioGaia financed part of the study; NCT03986476. (König et al. 2024, PLoS One)

65 adults with diarrhea-predominant irritable bowel syndrome.

Small and large intestinal permeability and other gut barrier markers did not change with either product. In the single-strain group, serum IL-6 tended to fall (p = 0.052) and symptoms eased at 3 weeks without reaching significance; only the two-strain group improved significantly at 3 weeks. At 6 weeks no symptom differed from placebo.

5
Testosterone in healthy men aged 55 to 65
PubMed

Randomized, double-blind, placebo-controlled three-arm trial of 1 or 10 billion CFU a day versus placebo for 12 weeks; every capsule, placebo included, had 5 mcg vitamin D3; BioGaia AB is the registered sponsor and one author is a BioGaia employee; NCT04577625. (Ljunggren et al. 2024, Contemp Clin Trials Commun)

57 healthy men aged 55 to 65 in Sweden.

The primary outcome was null: neither dose changed testosterone. Triglycerides fell in the high-dose group from 1.54 to 1.20 mmol/L and differed from placebo at 6 and 12 weeks (p = 0.013 and 0.014), a secondary finding without correction for multiple tests. Hemoglobin and red cell values dipped in the high-dose group at 6 weeks and returned to baseline by 12 weeks.

6
Open-label study in 10 adults aged 50 to 69
PubMed

Single-arm open-label study without a placebo group: 10 billion live cells of ATCC PTA 6475 a day in two capsules for 12 weeks at Hiroshima University; capsules made by and study funded by BioGaia Japan. (Noda et al. 2026, Biosci Microbiota Food Health)

10 adults aged 50 to 69 in Japan.

Sex hormones did not change notably. Body fat percentage, blood pressure and some inflammation-related values fell from baseline, and fecal Butyricimonas, Holdemania and Odoribacter rose. With no comparison group, these changes cannot be credited to the probiotic.

Side effects and drug interactions

Common Potential side effects

Adverse events did not differ from placebo in the 12-month trial in women aged 75 to 80.
In the 2-year trial, treatment-related adverse events were reported by 57.5% (high dose), 45.0% (low dose) and 64.6% (placebo), with no treatment-related serious events.
In the testosterone trial, hemoglobin and red cell values dipped at the high dose at 6 weeks and were back to baseline by 12 weeks.
None of the cited trials tested pregnant or breastfeeding women or children; ask a clinician first.
NCCIH notes that the risk of harmful effects from probiotics is greater in people with severe illnesses or compromised immune systems; ask a doctor before using live probiotics in those situations.
BioGaia funded or co-funded the bone trials and the Japanese pilot study, sponsored the testosterone trial, and BioGaia employees co-authored the gut and testosterone trials.

Important Drug interactions

Prednisolone: in a 7-day course in healthy adults, the strain did not change bone turnover markers or glucose versus placebo.
Vitamin D supplements: Osfortis adds 10 mcg (400 IU) vitamin D per 2 capsules; count it in your daily total.
Immunosuppressive medicines: ask a clinician before using any live probiotic.
No other drug interactions were reported in the cited trials.

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Frequently asked questions about Limosilactobacillus reuteri ATCC PTA 6475 (BioGaia Osfortis®)

What is BioGaia Osfortis?

It is a capsule with the probiotic strain Limosilactobacillus reuteri ATCC PTA 6475 plus vitamin D, made by the Swedish company BioGaia: 10 billion CFU and 10 mcg (400 IU) vitamin D per two capsules, taken as one capsule twice daily. The research tested the strain, either alone or against a placebo that had the same vitamin D, so it does not test the combination against nothing.

Does L. reuteri 6475 support bone density?

The two main trials disagree. In women aged 75 to 80 with low bone density, 12 months of the strain alone, without vitamin D, slowed loss of volumetric bone density at the shin versus placebo, though hip and spine density did not differ significantly. In 239 women in early menopause, 2 years of capsules matching the Osfortis formula made no difference to bone loss, the main outcome, or bone turnover versus a vitamin D placebo.

Is ATCC PTA 6475 the same as BioGaia Protectis?

No. Protectis is strain DSM 17938, which has its own research, mostly in infants. A blend sold as Gastrus combines the two strains, and results from blends do not show what ATCC PTA 6475 does on its own.

Can L. reuteri 6475 raise testosterone?

Mouse studies suggested it, but a 12-week placebo-controlled trial in healthy men aged 55 to 65 found no change in testosterone at either 1 or 10 billion CFU a day, and a small open-label study saw no notable change in sex hormones.

What is Limosilactobacillus reuteri ATCC PTA 6475?

Limosilactobacillus reuteri ATCC PTA 6475 is a single probiotic strain that BioGaia sells as Osfortis®, a capsule that also contains vitamin D (10 mcg, or 400 IU, per two capsules). It is a different strain from BioGaia Protectis (DSM 17938). The trials tested the strain, not Osfortis itself.

What is Limosilactobacillus reuteri ATCC PTA 6475 used for?

Limosilactobacillus reuteri ATCC PTA 6475 is researched primarily for Bone Health. In 90 women aged 75 to 80 with low bone density, 10 billion CFU a day of the strain alone, without vitamin D, cut 12-month loss of shin volumetric bone density to 0.83% versus 1.

What is the recommended dosage of Limosilactobacillus reuteri ATCC PTA 6475?

The clinically studied dose is 10 billion CFU a day (5 billion twice daily): 12 months, no vitamin D, in older women; 2 years with 400 IU vitamin D a day in every group, placebo included, in early postmenopausal women (1 billion CFU a day also tested). Always follow the product label and check with a healthcare provider for personal advice.

Is Limosilactobacillus reuteri ATCC PTA 6475 safe, and does it have side effects?

Side effects and cautions reported for Limosilactobacillus reuteri ATCC PTA 6475 include: Adverse events did not differ from placebo in the 12-month trial in women aged 75 to 80. In the 2-year trial, treatment-related adverse events were reported by 57.5% (high dose), 45.0% (low dose) and 64.6% (placebo), with no treatment-related serious events. It may also interact with some medications. Limosilactobacillus reuteri ATCC PTA 6475 is not right for everyone, so check with a healthcare provider first if you are pregnant or breastfeeding, have a medical condition, or take prescription medication.

Does Limosilactobacillus reuteri ATCC PTA 6475 interact with any medications?

Possible interactions include: Prednisolone: in a 7-day course in healthy adults, the strain did not change bone turnover markers or glucose versus placebo. Vitamin D supplements: Osfortis adds 10 mcg (400 IU) vitamin D per 2 capsules; count it in your daily total. If you take prescription medication, check with a pharmacist or doctor before using it.

How strong is the scientific evidence for Limosilactobacillus reuteri ATCC PTA 6475?

NutraSmarts rates the evidence for Limosilactobacillus reuteri ATCC PTA 6475 as Limited (2 out of 5). It is backed by 6 study summaries and 16 cited references summarized on this page. A higher rating reflects more, larger, and better-designed human studies.

References(16 citations)

Evidence ratings on NutraSmarts are based on the totality of human clinical research, with emphasis on randomized controlled trials, meta-analyses, and systematic reviews. The references below directly support claims made throughout this page.

  1. Nilsson AG, Sundh D, Bäckhed F, Lorentzon M. Lactobacillus reuteri reduces bone loss in older women with low bone mineral density: a randomized, placebo-controlled, double-blind, clinical trial. J Intern Med. 2018;284(3):307-317. doi: 10.1111/joim.12805.PubMedUsed to support: Randomized, double-blind, placebo-controlled trial in 90 women aged 75 to 80 with low bone mineral density (70 completed): 10 billion CFU a day of L. reuteri ATCC PTA 6475 for 12 months reduced loss of tibia total volumetric BMD versus placebo (-0.83% vs -1.85%, mean difference 1.02%, 95% CI 0.02 to 2.03) in the intention-to-treat analysis. Secondary bone outcomes showed smaller effects that were not significant in the intention-to-treat population. Adverse events did not differ. The strain was given as a powder without vitamin D and the placebo was maltodextrin. Funded by BioGaia AB, the Swedish Research Council and Sahlgrenska University Hospital; NCT02422082.
  2. Gregori G, Pivodic A, Magnusson P, Johansson L, Hjertonsson U, Brättemark E, Lorentzon M. Limosilactobacillus reuteri 6475 and Prevention of Early Postmenopausal Bone Loss: A Randomized Clinical Trial. JAMA Netw Open. 2024;7(6):e2415455. doi: 10.1001/jamanetworkopen.2024.15455.PubMedUsed to support: Randomized, double-blind, placebo-controlled 2-year trial in 239 early postmenopausal women aged 50 to 60: 0.5 or 5 billion CFU twice daily, in capsules with 200 IU vitamin D3 that the placebo also contained, had no effect on tibia total volumetric BMD (primary outcome), hip or spine BMD, or bone turnover markers versus placebo. A prespecified analysis found an interaction between BMI and treatment at 2 years. Funded by BioGaia AB, the Swedish Research Council and Sahlgrenska University Hospital; NCT04169789.
  3. Gregori G, Johansson L, Silberberg L, Imberg H, Magnusson P, Lind M, Lorentzon M. Prevention of glucocorticoid-induced impairment of bone metabolism-a randomized, placebo-controlled, single centre proof-of-concept clinical trial. JBMR Plus. 2025;9(4):ziaf031. doi: 10.1093/jbmrpl/ziaf031.PubMedUsed to support: Randomized, double-blind, placebo-controlled proof-of-concept trial in 50 healthy adults aged 18 to 45: 10 billion CFU a day for 2 weeks, then open-label prednisolone 25 mg a day for 7 days. CTX, PINP and osteocalcin changes and mean blood glucose did not differ from placebo. Funding included BioGaia AB; NCT04767711.
  4. Li P, Ji B, Luo H, Sundh D, Lorentzon M, Nielsen J. One-year supplementation with Lactobacillus reuteri ATCC PTA 6475 counteracts a degradation of gut microbiota in older women with low bone mineral density. NPJ Biofilms Microbiomes. 2022;8(1):84. doi: 10.1038/s41522-022-00348-2.PubMedUsed to support: Secondary analysis of 20 good and poor bone responders from the 12-month trial in older women: good responders had higher gut microbial gene richness, an improved inflammatory state and less E. coli enrichment. States that BioGaia AB funded the original randomized trial.
  5. Li P, Sundh D, Ji B, Lappa D, Ye L, Nielsen J, Lorentzon M. Metabolic Alterations in Older Women With Low Bone Mineral Density Supplemented With Lactobacillus reuteri. JBMR Plus. 2021;5(4):e10478. doi: 10.1002/jbm4.10478.PubMedUsed to support: Post hoc analysis of serum metabolomics from the 12-month trial in older women: metabolite profiles separated the probiotic and placebo groups and butyrylcarnitine was higher on the probiotic, but no single metabolite remained significant after correction for multiple testing. States that BioGaia AB provided partial funding for the original trial.
  6. König J, Roca Rubio MF, Forsgård RA, Rode J, Axelsson J, Grompone G, Brummer RJ. The effects of a 6-week intervention with Limosilactobacillus reuteri ATCC PTA 6475 alone and in combination with L. reuteri DSM 17938 on gut barrier function, immune markers, and symptoms in patients with IBS-D-An exploratory RCT. PLoS One. 2024;19(11):e0312464. doi: 10.1371/journal.pone.0312464.PubMedUsed to support: Exploratory randomized placebo-controlled trial in 65 adults with diarrhea-predominant IBS: ATCC PTA 6475 alone or with DSM 17938 for 6 weeks did not change gut permeability; IL-6 tended to fall with the single strain (p = 0.052), and symptoms improved significantly at 3 weeks only with the two-strain product, with no symptom differences at 6 weeks. Two authors are BioGaia employees; NCT03986476. A correction notice was published in 2025.
  7. Ljunggren L, Butler E, Axelsson J, Åström M, Ohlsson L. Effects of probiotic supplementation on testosterone levels in healthy ageing men: A 12-week double-blind, placebo-controlled randomized clinical trial. Contemp Clin Trials Commun. 2024;39:101300. doi: 10.1016/j.conctc.2024.101300.PubMedUsed to support: Randomized, double-blind, placebo-controlled 12-week trial in healthy men aged 55 to 65 (57 included): 1 or 10 billion CFU a day of ATCC PTA 6475 did not change testosterone; triglycerides fell in the high-dose group. All capsules, placebo included, contained 5 mcg vitamin D3. One author is a BioGaia employee; NCT04577625 (BioGaia AB sponsor).
  8. Noda M, Danshiitsoodol N, Kanno K, Yonezawa S, Ishida R, Sugiyama M. Effect of probiotic Limosilactobacillus reuteri on a serum sex-hormone- and metabolic-syndrome-related health evaluation: a single-arm open-label pilot study. Biosci Microbiota Food Health. 2026;45(1):42-50. doi: 10.12938/bmfh.2025-020.PubMedUsed to support: Single-arm open-label pilot study in 10 adults aged 50 to 69 given 10 billion live ATCC PTA 6475 cells a day for 12 weeks: no notable change in sex hormones; body fat percentage, blood pressure and some inflammation-related values fell from baseline. No placebo group. Funded by BioGaia Japan.
  9. Cruchet S, Hirsch S, Villa-López D, Moreno-Portillo M, Palomo JC, Abreu-Abreu AT, Abdo-Francis JM, Jiménez-Gutiérrez C, Rojano M, López-Velázquez G, Gutiérrez-Castrellón P. Limosilactobacillus reuteri DSM 17938 and ATCC PTA 6475 for the treatment of moderate to severe irritable bowel syndrome in adults: a randomized controlled trial. Front Gastroenterol (Lausanne). 2023;2:1296048. doi: 10.3389/fgstr.2023.1296048.PubMedUsed to support: Randomized, double-blind, placebo-controlled trial in 140 adults with IBS of a blend of DSM 17938 and ATCC PTA 6475 (not this strain alone) twice daily with standard care for 14 weeks: symptom scores improved versus placebo from week 6 and fecal calprotectin was lower at the end; adverse events were similar between groups. BioGaia partly funded the trial and supplied the product and placebo.
  10. Dore MP, Bibbò S, Pes GM, Francavilla R, Graham DY. Role of Probiotics in Helicobacter pylori Eradication: Lessons from a Study of Lactobacillus reuteri Strains DSM 17938 and ATCC PTA 6475 (Gastrus®) and a Proton-Pump Inhibitor. Can J Infect Dis Med Microbiol. 2019;2019:3409820. doi: 10.1155/2019/3409820.PubMedUsed to support: Randomized placebo-controlled 2-site trial of L. reuteri Gastrus, which the title identifies as strains DSM 17938 and ATCC PTA 6475 (a blend, not this strain alone), given with pantoprazole but no antibiotics to adults with H. pylori infection: cure rates were 12.5% versus 4.1% with placebo, and recruitment stopped after 56 people because of the low cure rate; NCT03404440.
  11. Britton RA, Irwin R, Quach D, Schaefer L, Zhang J, Lee T, Parameswaran N, McCabe LR. Probiotic L. reuteri treatment prevents bone loss in a menopausal ovariectomized mouse model. J Cell Physiol. 2014;229(11):1822-30. doi: 10.1002/jcp.24636.PubMedUsed to support: Mouse study (animal work): L. reuteri ATCC PTA 6475 protected ovariectomized mice from bone loss and lowered osteoclast markers Trap5 and RANKL and bone marrow CD4+ T cells; it also suppressed osteoclast formation in vitro.
  12. Quach D, Parameswaran N, McCabe L, Britton RA. Characterizing how probiotic Lactobacillus reuteri 6475 and lactobacillic acid mediate suppression of osteoclast differentiation. Bone Rep. 2019;11:100227. doi: 10.1016/j.bonr.2019.100227.PubMedUsed to support: Lab study: conditioned supernatant from L. reuteri 6475 and its fatty acid lactobacillic acid suppressed osteoclast differentiation, with lower NF-kB and p38 activation, signaling partly through the GPR120 receptor.
  13. Poutahidis T, Springer A, Levkovich T, Qi P, Varian BJ, Lakritz JR, Ibrahim YM, Chatzigiagkos A, Alm EJ, Erdman SE. Probiotic microbes sustain youthful serum testosterone levels and testicular size in aging mice. PLoS One. 2014;9(1):e84877. doi: 10.1371/journal.pone.0084877.PubMedUsed to support: Mouse study (animal work): aging male mice given L. reuteri ATCC PTA 6475 in drinking water had larger testes and higher serum testosterone than age-matched controls.
  14. BioGaia AB. BioGaia Osfortis: probiotic capsules (product page). BioGaia AB website. 2026;Accessed 2026..SourceUsed to support: Not PubMed-indexed; manufacturer product page. States that the capsules contain L. reuteri ATCC PTA 6475, a strain originally developed and patented by BioGaia, lists maltodextrin, the strain, calcium stearate, vitamin D3 and an HPMC capsule as ingredients, and directs one capsule twice daily.
  15. Vitacost. BioGaia Osfortis with Vitamin D, 60 probiotic capsules (Supplement Facts panel). Vitacost product listing. 2026;Accessed 2026..SourceUsed to support: Not PubMed-indexed; retailer listing reproducing the Supplement Facts panel: per 2-capsule serving, 10 mcg (400 IU) vitamin D as cholecalciferol and 10 billion CFU of L. reuteri ATCC PTA 6475.
  16. National Center for Complementary and Integrative Health, National Institutes of Health. Probiotics: What You Need To Know. NCCIH (NIH). 2019;Online fact sheet, last updated August 2019; accessed 2026-10-31..SourceUsed to support: Not PubMed-indexed; US government fact sheet. States that the risk of harmful effects from probiotics is greater in people with severe illnesses or compromised immune systems, and that severe or fatal infections have been reported in premature infants given probiotics. It gives no guidance on timing probiotics around antibiotics.