Skip to main content
Evidence-Based Supplement Research
Evidence-Based Supplement Research
Pillser
Search
Sign UpLog In

Lactobacillus reuteri

What does the research say about Lactobacillus reuteri?

4 health outcomes synthesised

Research on Lactobacillus reuteri has been studied across 4 health outcomes related to oral health, predominantly in populations with periodontitis or gingivitis. The strongest evidence is for reducing bleeding on probing (BOP), with 5 studies forming the largest body of research, though the overall evidence strength is low. Most studies use lozenges providing 1×10⁹ CFU per day, with effects observed over durations ranging from 14 days to 12 months.

Strongest evidence: No outcomes reach high or moderate evidence strength; all 4 are classified as low. The largest body of research (5 studies) examines Lactobacillus reuteri for reduced bleeding on probing (BOP), where 3 of 5 studies reported benefit (2 with moderate or large effects), though 2 studies were neutral. The evidence is considered preliminary and mixed.

Mixed or weaker evidence: For improved clinical attachment (5 studies), 3 reported benefit, 1 was neutral, and 1 showed harm in diabetic patients — a concerning population-specific finding. For reduced probing depth (3 studies), only 1 reported a large benefit while 2 neutral studies in diabetic patients found no effect. For reduced plaque index (3 studies), 2 showed small-to-moderate benefit and 1 was neutral. All outcomes carry low evidence strength.

Effective dose patterns: The most common dose across outcomes is 1×10⁹ CFU per day, typically delivered as 1–2 lozenges daily. Study durations ranged from 14 days to 12 months, with median durations around 100–180 days depending on the outcome.

Population insights: Most studies enrolled patients with periodontitis or gingivitis, including subgroups with diabetes. Neutral or harmful results were more common in diabetic populations, suggesting that response may differ in this group. One study in adolescents with betel quid chewing habits showed benefit for plaque reduction.

Notable caveats: The evidence base is small (3–5 studies per outcome) and preliminary. Publication bias is a concern, particularly for positive results. Several high-quality RCTs (2024–2025) showed neutral effects, indicating benefits may not be consistent. One study in diabetic patients reported significant harm for clinical attachment, which warrants caution.

Frequently asked

  • What is Lactobacillus reuteri good for according to research?
    Based on the available research, Lactobacillus reuteri has been studied for oral health outcomes including reducing bleeding on probing, improving clinical attachment, reducing probing depth, and lowering plaque index. The evidence is strongest for bleeding on probing (5 studies), though all outcomes have low evidence strength and results are mixed.
  • What dose of Lactobacillus reuteri is typically used in studies?
    The most common dose across studies is 1×10⁹ CFU per day, typically delivered as 1–2 lozenges daily. For bleeding on probing, the effective dose was 1–2 lozenges per day, while for clinical attachment and probing depth, the dose was 1×10⁹ CFU/day. Study durations ranged from 14 days to 12 months.
  • Who benefits most from Lactobacillus reuteri according to research?
    Most studies enrolled patients with periodontitis or gingivitis. However, neutral results were more common in diabetic patients, and one study in diabetic patients reported harm for clinical attachment. The strongest signal for benefit came from studies in non-diabetic periodontitis patients. One study in adolescents with betel quid chewing habits showed benefit for plaque reduction.
  • Are there caveats or limitations in the research on Lactobacillus reuteri?
    Yes, major caveats include small sample sizes (3–5 studies per outcome), preliminary evidence, potential publication bias favoring positive results, and inconsistent effects across populations. Several high-quality 2024–2025 RCTs found neutral effects, and one study in diabetic patients showed harm. The evidence should be considered preliminary.
  • Does Lactobacillus reuteri help reduce bleeding on probing (BOP)?
    In 5 studies, 3 reported benefit (2 with moderate or large effects) while 2 found neutral results. The evidence is mixed and low-strength, with caveats that many studies did not reach statistical significance. Effects were seen over 3 weeks to 12 months, mostly in periodontitis patients.
  • Does Lactobacillus reuteri improve clinical attachment?
    Of 5 studies, 3 reported benefit (moderate effects), 1 was neutral, and 1 showed harm in diabetic patients. The evidence is low-strength and mixed, with concerns about population-specific risks. The effective dose was 1×10⁹ CFU/day, with effects observed at 56–180 days.

Most-studied combinations with Lactobacillus reuteri

most supplement research is combination research
Also studied with:Lactobacillus reuteri ATCC PTA 5289 (2)
Back to top