Mastic Gum

Mastic's triterpenic acids disrupt the cell membrane of Helicobacter pylori and other bacteria, causing structural damage visible under the electron microscope; the resin is active against several H. pylori strains in vitro, including some antibiotic-resistant ones. In the stomach, mastic appears to reduce acid secretion modestly and to protect the mucosa, possibly by increasing mucus and by antioxidant effects on the epithelium. Its anti-inflammatory activity includes inhibition of NF-κB signaling and reduced production of TNF-α and other cytokines, which may be relevant to gastritis and inflammatory bowel disease. The triterpenes also inhibit bacterial biofilm formation in the mouth and have mild antifungal action. However, mastic's main polymer is poorly soluble, which limits how much of the active fraction reaches the stomach lining and may explain why eradication of H. pylori in people is incomplete.

Human evidence is small and mixed. The strongest trial is a 2010 Greek randomized, placebo-controlled study of 148 people with functional dyspepsia, in which 350 mg of mastic three times daily for 3 weeks significantly improved overall symptoms — particularly stomach pain, heartburn, and dull ache — compared with placebo. For H. pylori, a 2010 pilot RCT of 52 patients found that 350 mg or 1.05 g of mastic three times daily for 14 days eradicated the infection in only 4 of 13 and 5 of 13 patients respectively, versus 11 of 13 with standard triple therapy. A 2007 study in Scotland found pure mastic did not eradicate H. pylori in mice or in a small human series, while a later Greek trial found adding mastic to triple therapy did not improve eradication. A 1984 double-blind trial of 38 people with duodenal ulcers reported healing in 70% on 1 g mastic daily versus 22% on placebo, but it has not been replicated with modern methods. Pilot studies in Crohn's disease showed reduced inflammatory markers over 4 weeks without a control group. Chewing-gum studies show reduced oral bacteria and plaque. Overall, mastic is a reasonable adjunct for indigestion with a plausible antimicrobial action, but it does not reliably clear H. pylori on its own.

Triterpenic acids (masticadienonic acid, isomasticadienonic acid, oleanonic acid), natural polymer (cis-1,4-poly-beta-myrcene), essential oil (alpha-pinene, myrcene), verbenone, linalool

Mastic resin is largely insoluble in water and only partially dissolves in stomach contents; the triterpenic acids that provide most of the activity are better absorbed when the resin is taken with food containing some fat. Studies suggest removing the insoluble polymer fraction improves bioavailability and antibacterial activity, and some newer products use this 'total mastic extract without polymer' approach. Absorbed triterpenes are detectable in the bloodstream and are metabolized in the liver. Chewing the raw resin releases the essential oil in the mouth but delivers less of the triterpenic fraction to the stomach than powdered capsules.

• Mastic-flavored liqueur (mastika), ice cream, and pastries in Greece and the eastern Mediterranean
• Mastic chewing gum (traditional Chios product)
• Used as a spice in Middle Eastern and Turkish cooking