Oregano Oil: Is It Good for You?

Reviewed by Dan Brennan, MD on October 22, 2020

Oregano oil, or oil of oregano, is extracted from the leaves of the oregano plant and has been used in folk medicine for centuries as a deterrent against illness. Today, many people still use oregano oil to fight infections and the common cold despite its renowned bitter, unpleasant taste.

Although more research is needed into the health benefits of oregano oil, studies have confirmed that it has the following properties:

  •  Antimicrobial
  • Antiviral
  • Antifungal
  • Antioxidants
  • Anti-inflammatory 
  • Antidiabetic
  • Cancer suppressor agents

Nutrition Information

One teaspoon of dried oregano leaves contains: 

  • Calories: 2.65
  • Protein: 0.09 gram
  • Fat: 0.04 gram
  • Carbohydrates: 0.69 gram
  • Fiber: 0.42 gram
  • Sugar: 0.04 gram

Oregano is a good source of: 

Oregano is also an excellent source of Vitamin K. Studies have shown that Vitamin K is important for bone health and regulating blood sugar.

Oregano oil also contains antioxidants which help stop free radicals from causing damage to your cells that can lead to serious diseases such as cancer.

Potential Health Benefits of Oregano Oil

Oregano oil is a rich source of vitamins and minerals. However, the same thing that makes oregano oil so potent can also create complications for people with certain medical conditions. 

Research has found a number of potential health benefits to consuming oregano oil: 

Antibacterial Properties

Several studies have shown the powerful antibacterial properties of oregano oil, even against antibiotic resistant strains of bacteria.

In one study that tested the antibacterial effects of a range of essential oils, oregano oil was found to be the most powerful inhibitor of bacterial growth.

Because of its ability to protect against bacterial infection, topical oregano oil has been shown to be effective in wound treatment and healing, even killing off methicillin-resistant Staphylococcus aureus (MRSA).

Anti-Inflammatory Effects

In addition to being a powerful antimicrobial agent, oregano oil also has anti-inflammatory effects. One study showed that oregano essential oil significantly inhibited several inflammatory biomarkers in skin. 

Improvement of Acne

Because of its combined antibacterial and anti-inflammatory properties, oregano oil may help improve the appearance of acne by reducing blemishes. Since using oral antibiotics to treat acne has a range of potential side effects, oregano oil may provide a safe and effective alternative when used topically.

Potential Risks of Oregano Oil

Because oregano oil has such potent ingredients, you should consult with your doctor before taking it or any other supplement. Consider the following before using oregano oil either internally or topically:


Because oregano oil is such a powerful antimicrobial agent, it can also be toxic to humans. Taken in large doses, oregano oil can even be lethal. Only use the recommended amount of oregano to yield its benefits. Further studies into the toxic effect of oil of oregano on humans is needed.

Skin Irritation

Although oregano oil can help some skin ailments like acne, it may be irritating for people with sensitive skin. Don’t apply undiluted oregano oil directly to your skin. Patch test any products containing oregano oil to ensure they won’t cause any adverse effects. Additional research on skin irritation caused by oregano oil on humans is required.

Pregnancy Concerns

The effects of oregano oil on someone who is pregnant or breastfeeding are inconclusive. If you’re pregnant or breastfeeding a baby, it is best to look for an alternative. 

Medication Interference

Avoid oregano oil if you’re already taking a diuretic, as their side effects may be compounded. Since oregano has natural diuretic properties, it may interfere with the action of lithium and similar medications. 

Show Sources


Biochimie Open: “Anti-inflammatory, tissue remodeling, immunomodulatory, and anticancer activities of oregano ( Origanum vulgare) essential oil in a human skin disease model.”

Frontiers in Microbiology: “Bactericidal Property of Oregano Oil Against Multidrug-Resistant Clinical Isolates.”

Korean Journal of Veterinary Research: “Primary dermal irritation study of oregano oil in rabbits.”

Molecules: “Essential Oils of Oregano: Biological Activity beyond Their Antimicrobial Properties.”

Molecules: “Origanum vulgare L. Essential Oil as a Potential Anti-Acne Topical Nanoemulsion-In Vitro and In Vivo Study.”

Moscow University Biological Sciences Bulletin: “Cytogerontological studies of biological activity of oregano essential oil.”

Open Heart: “The Health Benefits of Vitamin K.”

Pathogens: “Antimicrobial Activity of Six Essential Oils Against a Group of Human Pathogens: A Comparative Study.”

The Korean Journal of Laboratory Animal Science: “Acute Toxicity Evaluation of Oregano Oil in Rats (2004).”

Review of Nutrition: “Antioxidants in Human Health and Disease.”

USDA FoodData Central: “Spices, Oregano, Dried.”

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