Oregano oil is made from a shrub native to the Mediterranean region. Oil of oregano has been used for cooking and healing purposes for centuries. It can be consumed and applied to most body parts, although you should avoid getting it in your eyes. Most of its benefits are related to antimicrobial and antioxidant activity. Oil of oregano isn’t dangerous, but it tends to cause strong tingling sensations wherever it's applied.
Oregano oil acts as an antimicrobial, especially against many species of bacteria and fungi. Consequently, adding a few drops of oregano oil to your toothbrush is a great way to clean your mouth and freshen your breath. Perhaps the strongest antiseptic compound in oregano oil is called carvacrol, which also acts as a mild anti-inflammatory. Carvacrol and other compounds in oregano oil can be effective in combating pimples, canker sores and herpes lesions. Carvacrol is mainly responsible for the oil's tingling or mild burning sensation, especially when it's applied to gums, open sores or minor cuts.
Oil of oregano is a strong antioxidant, which helps to eliminate harmful free radicals and protect tissues such as blood vessels from damage and deterioration. One of the main antioxidant compounds in oregano is quercetin, which is also a good anti-inflammatory because it’s able to inhibit the release of histamine in your body. Histamine release is what causes most allergy symptoms. In terms of potency, oil of oregano is comparable in antioxidant ability to vitamin E oil.
Oregano oil is generally recognized as safe by the U.S. Food and Drug Administration, but people with allergies to herbs from the mint family, such as mint, thyme, basil, lavender or marjoram, should be cautious. Oil of oregano doesn't interact with medications, but large doses of it may impact the effectiveness of insulin, so diabetics should consult their doctor before supplementing with it. Pregnant women should also be careful with oregano oil because it stimulates blood flow in the uterus, which can potentially trigger a spontaneous abortion.
Oil of oregano is the most potent form of the herb, so if you are concerned with how you’ll respond to it, consider taking oregano capsules first or adding some dried and ground oregano to your food. The strength of oregano oil, which is measured by the carvacrol content, also varies considerably. For example, brands of oregano oil vary in carvacrol strength from 40 to 70 percent, with the higher-percentage varieties offering more medicinal value.
- Natural Standard Herb & Supplement Reference: Evidence-based Clinical Reviews; Catherine E. Ulbricht and Ethan M. Basch
- Principles and Practice of Phytotherapy: Modern Herbal Medicine; Simon Mills and Kerry Bone
Sirah Dubois is currently a PhD student in food science after having completed her master's degree in nutrition at the University of Alberta. She has worked in private practice as a dietitian in Edmonton, Canada and her nutrition-related articles have appeared in The Edmonton Journal newspaper.