Propolis, sometimes called "bee glue," is a resinous substance honeybees produce by combining collected tree and plant resins with their own secretions, used by the bees themselves to seal and sterilize the hive. Ancient Egyptian, Greek, and Roman physicians documented its use for wounds and infections.
Modern research into propolis has concentrated substantially on oral and dental health applications, where its antimicrobial and anti-inflammatory properties have been tested in a genuinely notable number of real human clinical trials.
Propolis has a real and consistent body of human clinical trial evidence specifically for oral health. A randomized, double-blind trial found a 5% propolis mouthwash produced significant reductions in dental plaque (24%) and gingival index (40%) after 90 days. A separate trial in patients undergoing periodontal maintenance found propolis toothpaste produced a statistically significant reduction in periodontal pocket depth compared to placebo.
A systematic review evaluating propolis mouthwashes identified 9 clinical trials (333 subjects) and found propolis showed "good efficacy on plaque and gingivitis in all of the included studies" — but the same review noted "most of the included studies showed high risk of bias," and heterogeneity meant no formal meta-analysis could be performed. Given consistent positive direction across multiple real trials, but reviewers' own acknowledgment of high bias risk, "Limited-Moderate" is the honest rating.
Collected directly from beehives; used in raw resin form, or extracted into tinctures, capsules, and topical preparations.