Oregano

Also called

Wild Marjoram, Pot Marjoram, Winter Marjoram

Older scientific names

Origanum floridum Salisb., Thymus origanum Kuntze

Traditional use

These are traditional uses, not proven treatments.

• Oregano has a long history of traditional use for:

  • Breathing problems: colds, fever, cough and bronchitis
  • Stomach ache and digestive upset
  • Painful periods
  • Rheumatoid arthritis
  • Urinary problems
  • Parasites and bacterial infections

  In Iranian traditional medicine, it has been used to restore strength, loosen mucus, relieve gas and stimulate the body. It has also long been used as a cooking spice, and oregano oil has been applied for bacterial and fungal infections.[1]Study

  Technical detail: tonic, expectorant, carminative, stimulant; antiparasitic and antibacterial.

Laboratory & animal research

Lab and animal results show what might be worth studying in people. They don't show that the herb has these effects in humans.

• In lab tests, an oregano extract rich in natural plant compounds (mainly rosmarinic acid) showed strong antioxidant activity and slowed the growth of bacteria and of a common mold (Aspergillus niger). In mice with chemically damaged livers, the extract reduced signs of liver damage and restored the liver's own protective enzymes. Oregano's essential oil is rich in carvacrol and thymol, which can make up about 70% of the oil in some types. Research on how these compounds fight germs comes from lab and food studies. These are lab and animal findings, not established effects in people.[4]Study

  Technical detail: Origanum vulgare ssp. vulgare hydroalcoholic extract: rosmarinic acid 12.83 mg/g, plus chlorogenic acid, hyperoside, isoquercitrin, rutin, quercitrin and luteolin; total polyphenols 94.69 mg/g. CUPRAC, FRAP and superoxide-scavenging assays; bacterial inhibition zones 16–19 mm; Aspergillus niger MIC 19.53 µg/mL. Carbon-tetrachloride hepatotoxicity model: restored catalase, superoxide dismutase and glutathione peroxidase and reduced lipid peroxidation. Other volatiles: gamma-terpinene, p-cymene. Proposed antimicrobial mechanisms: enzyme inhibition, efflux-pump inhibition, biofilm disruption, membrane damage.

Research in people

• In a small study, 14 adults with gut parasites found in stool tests took 600 mg of oregano oil a day for 6 weeks. One parasite (Entamoeba hartmanni) cleared in all 4 people who had it, another (Endolimax nana) cleared in the 1 person who had it, and a third (Blastocystis hominis) cleared in 8 of 11 people, with levels falling in 3 more. Digestive symptoms improved in 7 of the 11 people with Blastocystis. The study was small, had no comparison group and everyone knew what they were taking, so it is early evidence, not proof.[5]Study

  Technical detail: open-label, not blinded, not placebo-controlled; emulsified oil of Mediterranean oregano (Origanum vulgare).

• In a US trial, 40 people who'd had skin surgery used a 3% oregano extract ointment or plain petroleum jelly on their wound. Fewer oregano wounds grew Staphylococcus aureus bacteria (19% vs 41%), and 1 person in the oregano group got a skin infection compared with 3 in the petroleum jelly group. Overall scars looked about the same, though the oregano group did better on scar color and flexibility. It was a small trial.[6]Review or trial

  Technical detail: randomized, double-blind, petrolatum-controlled; cultures on day 12; Patient and Observer Scar Assessment Scale on days 12, 45 and 90; cellulitis 1 vs 3.