Benefits
Gingival index reduction LF + LPO tablets
In a randomized double-blind placebo-controlled trial in healthy adults, high-dose tablets (lactoferrin 60 mg/d + LPO 7.8 mg/d) significantly reduced the Gingival Index vs placebo. These oral tablets dissolve in and act locally in the mouth, and the single trial was funded by the tablet maker (Morinaga Milk Industry), with efficacy analyzed in 109 of 150 randomized adults.
Toothpaste enzyme system gingivitis 13-week RCT
A double-blind randomized parallel-group home-use RCT in healthy non-smokers tested a toothpaste containing enzymes (amyloglucosidase + glucose oxidase + LPO) plus proteins (lactoferrin + lysozyme), reflecting natural saliva composition, vs a commercial control. The three-enzyme system reproduces the natural salivary defense mechanism rather than introducing exogenous antimicrobials.
Plaque and gingivitis in xerostomia
In patients with radiation-induced xerostomia, LPO toothpaste reduced the rate of supragingival plaque formation, and gingival inflammation was lower. Particularly relevant population, since xerostomia patients have impaired natural salivary defense. This was a single-blind pilot crossover in only 12 patients using an LPO toothpaste (topical, rinse-and-spit), which limits any firm conclusion.
Hypothiocyanite antimicrobial production (mechanism)
LPO oxidizes salivary thiocyanate (SCN⁻) using H₂O₂ as cofactor to generate hypothiocyanite (OSCN⁻) — a broad-spectrum antimicrobial active against both Gram-positive and Gram-negative pathogens. This defense pathway is delivered locally by LPO oral-care products (toothpaste and dissolving tablets), not by systemic supplementation.
Three-enzyme synergistic system
Amyloglucosidase + glucose oxidase generate H₂O₂ from glucose, which LPO then uses with thiocyanate to produce hypothiocyanite. Self-sustaining enzyme cascade — provides continuous low-level antimicrobial activity from dietary glucose substrate without exogenous H₂O₂ delivery.
Oral microbiome rebalancing (proposed mechanism)
Hypothiocyanite exerts selective antimicrobial pressure that could favor commensal species over periodontal pathogens rather than acting as a blanket antibacterial. This is a proposed mechanism: the cited oral-care trials measured gingival and plaque scores, not oral-microbiome composition, and none reports a Neisseria increase.
Systematic review (D'Agostino & Dolci, 2025)
A systematic review found that toothpaste with amyloglucosidase + glucose oxidase + LPO + lysozyme + lactoferrin is effective for preventing gingivitis and managing gingival inflammation short-term and long-term, via reduced MGI, BI, and PI scores. Honest limitation acknowledged in the review: limited number of eligible studies.
Mechanism of action
Hypothiocyanite generation (LPO-SCN-H₂O₂ system)
The core LPO mechanism: oxidation of thiocyanate using H₂O₂ as cofactor to generate hypothiocyanite, a broad-spectrum antimicrobial. The natural salivary defense pathway.
Three-enzyme synergistic system
Amyloglucosidase + glucose oxidase cascade generates H₂O₂ from dietary glucose, which LPO uses to produce hypothiocyanite. Self-sustaining cascade providing continuous low-level antimicrobial activity.
Gram-positive and Gram-negative pathogen inhibition
Hypothiocyanite has broad-spectrum activity against periodontal pathogens including Streptococcus mutans, Porphyromonas gingivalis, and Aggregatibacter actinomycetemcomitans — covering the major Gram-positive and Gram-negative oral pathogens.
Heme B catalytic center + calcium binding
LPO contains an autocatalytic heme B center for the peroxidation reaction plus a calcium-binding site (Asp227) supporting structural stability. Standard heme peroxidase pharmacology with LPO-specific substrate preferences.
Oral microbiome shift toward health
In the mouth, selective pressure appears to favor commensal species (e.g., Neisseria) over periodontal pathogens, rebalancing the ORAL microbiome rather than acting as a blanket antibacterial. This is a local oral-cavity effect.
Salivary defense system reproduction
The natural salivary LPO plus thiocyanate plus H₂O₂ system can be reinforced LOCALLY by LPO-containing oral-care products (toothpaste, lozenges), which may help in xerostomia where saliva is reduced. This is a local oral-cavity effect, not systemic supplementation.
Clinical trials
Clinical evidence on Lactoperoxidase (LPO Salivary Enzyme System) for the indications and outcomes described.
healthy adults
Nakano M et al. 2019 (authors employed by Morinaga Milk Industry, which makes the tablets). Randomized double-blind placebo-controlled trial: 150 adults randomized, 109 analyzed for efficacy. High-dose tablets (lactoferrin 60 mg/d + LPO 7.8 mg/d) for 12 weeks significantly reduced the Gingival Index vs placebo. These are oral tablets that act locally in the mouth on gum inflammation, not a systemically absorbed supplement.
13-week double-blind randomized parallel-group home-use clinical trial in healthy non-smokers (mean MGI 2.00-2.75).
Clinical population described in trial publication.
13-week double-blind randomized parallel-group home-use clinical trial in healthy non-smokers (mean MGI 2.00-2.75). Toothpaste with a three-enzyme system (amyloglucosidase + glucose oxidase + LPO) plus lactoferrin and lysozyme vs commercial control (229 completed; study co-authored and funded by Unilever Oral Care). This is a rinse-and-spit toothpaste applied topically to the oral cavity, not a swallowed supplement.
Single-blind crossover 52-day trial in 12 patients with radiation-induced xerostomia.
12 patients with radiation-induced xerostomia
Single-blind crossover 52-day trial in 12 patients with radiation-induced xerostomia. LPO toothpaste reduced rate of supragingival plaque formation; gingival inflammation was lower. Small sample size in a clinically important population (xerostomia patients).