Supplement analysis backed by scientific evidence · PT

← All supplements
Limited evidenceImmunity

Monolaurin

Monolaurin (glycerol monolaurate) is a potent antimicrobial in a test tube and on a surface — that part is well established. What is missing is any human evidence that swallowing it produces an antiviral or antibacterial effect anywhere in the body, and the one randomized trial of a topical monolaurin gel failed its primary endpoint.

What the science says

  • Kills enveloped viruses and Gram-positive bacteria in vitro Moderate evidence

    Monolaurin disrupts lipid membranes and, at roughly 10-100 micrograms/mL, suppresses Staphylococcus aureus growth and blocks production of exotoxins including TSST-1. This is reproducible laboratory pharmacology and underpins its use as a food preservative and in device coatings — but in vitro potency is the starting point of a drug program, not evidence of clinical effect.

  • Works when applied topically in humans Limited evidence

    An in vivo study of glycerol monolaurate-coated tampons showed reduced S. aureus exotoxin production and lower vaginal IL-8, a genuine human biological effect. However, a randomized placebo-controlled trial of 5% monolaurin vaginal gel for bacterial vaginosis did not show a significantly better cure rate than placebo, which is the appropriate cautionary note about translating antimicrobial activity into clinical cure.

  • Oral monolaurin treats herpes, EBV, candida or "chronic viral load" Limited evidence

    There is no randomized human trial of oral monolaurin for any infection. Pharmacologically the claim is difficult: monolaurin is a monoacylglycerol, the normal end product of dietary fat digestion, and is absorbed and metabolized like one — reaching and sustaining the 10-100 micrograms/mL tissue concentrations that work in a dish from a 600-1,800 mg oral dose is not plausible. Testimonials, not trials, are what carry this category.

  • Coconut oil provides the same benefit Limited evidence

    Coconut oil is about 45-50% lauric acid, but almost entirely as triglyceride, not monolaurin, and reviews of coconut oil and immunity find no clinical evidence of antimicrobial benefit from eating it. Some monolaurin is formed by gut lipases during digestion, but not in quantities linked to any measured immune outcome.

Dosage & safety

Studied doseProducts are typically 300-600 mg per capsule or pellet, with labels suggesting 600-3,000 mg/day in divided doses, often escalated over a week. None of these doses come from human efficacy trials — they are label conventions. The human data that exist are topical: 5% gel formulations and device coatings.
SafetyMonolaurin has GRAS status as a food emulsifier and antimicrobial and is generally well tolerated orally, with GI upset, nausea and loose stools the main complaints at gram doses. Users frequently report early "die-off" symptoms; there is no evidence these represent microbial killing rather than GI irritation. In vitro, glycerol monolaurate is cytotoxic to genital epithelial cells at higher concentrations, which is relevant to enthusiasm for topical or intravaginal use outside tested formulations. The practical risk is substitution: monolaurin is not a treatment for herpes (antivirals are), for confirmed bacterial infection (antibiotics are), or for suspected chronic infection that has not been properly worked up. Not established in pregnancy or breastfeeding.

Scientific references

Where to buy

Vitacost, Monolaurin, 60 Capsules

View on iHerb

Referral link — this site may earn a commission on purchases.

Related in Immunity