Wise Mind Herbs

The information on this page has been prepared with reference to published scientific literature, not by a medically qualified expert. It is not medical advice. Any decision to use a supplement or herb-based product is your responsibility. Consult a suitably qualified medical professional, especially if you have underlying conditions. Remember, nothing is for everyone, and not everything sold is what it claims to be. Some things work for some people, some of the time.

Oregano - Oreganum vulgare

Oregano is an aromatic herb widely used in culinary applications that has garnered attention for its potential health benefits. This review examines the scientific evidence behind oregano's therapeutic properties based on peer-reviewed literature.

Botanical Classification and Common Names

The term "oregano" primarily refers to Origanum vulgare (common or wild oregano) from the Lamiaceae family. However, several plants are marketed as oregano:

• Origanum vulgare - True oregano, wild marjoram, European oregano
• Origanum vulgare subsp. hirtum - Greek oregano
• Origanum onites - Turkish oregano, Cretan oregano, pot marjoram
• Thymus capitatus (syn. Coridothymus capitatus) - Spanish oregano
• Lippia graveolens - Mexican oregano (not a true oregano, different family)
• Lippia origanoides - Puerto Rican oregano (not a true oregano)

It's important to note that marjoram (Origanum majorana) is closely related but distinct from oregano, though they are sometimes confused.

Active Compounds

Oregano's medicinal properties stem primarily from its essential oil components, including:

• Carvacrol (typically 40-70% in oregano essential oil)
• Thymol (0.5-10%)
• γ-Terpinene (5-10%)
• p-Cymene (5-10%)
• Rosmarinic acid
• Various flavonoids and phenolic acids

The composition varies significantly based on species, growing conditions, harvest time, and extraction method.

Health Benefits Supported by Scientific Evidence

Based on peer-reviewed studies, oregano has demonstrated the following properties:

1. Antimicrobial Activity

Oregano oil has shown significant antimicrobial properties against a wide range of pathogens, including bacteria (both gram-positive and gram-negative), fungi, and some viruses. Multiple studies confirm the broad-spectrum antimicrobial activity of oregano essential oil, with particularly strong effects against foodborne pathogens like E. coli, Salmonella, and Listeria monocytogenes.

2. Antioxidant Effects

Oregano ranks among the herbs with the highest antioxidant activity, primarily due to rosmarinic acid, carvacrol, and thymol. These compounds help neutralize free radicals and may protect cells from oxidative damage.

3. Anti-inflammatory Properties

Several studies have demonstrated that carvacrol and thymol possess anti-inflammatory properties. Oregano extract reduces inflammatory markers in both in vitro and animal models, suggesting potential benefit for inflammatory conditions.

4. Digestive Health

Oregano has been traditionally used for digestive issues, and some evidence supports its carminative (gas-reducing) and antispasmodic effects. Oregano oil capsules have proven more effective than placebo in improving symptoms of irritable bowel syndrome (IBS).

Conditions with Some Evidence of Benefit

While more robust clinical evidence is needed, preliminary research suggests oregano may help with:

• Respiratory infections (bronchitis, coughs)
• Intestinal parasites (particularly Blastocystis hominis, Entamoeba hartmanni, and Endolimax nana)
• Inflammatory skin conditions
• Mild pain relief (analgesic properties)
• Menstrual discomfort
• Blood sugar regulation (preliminary evidence)

Important Clarification on "Cures"

It's crucial to note that scientific literature does not support claims that oregano "cures" any medical condition. Rather, it may help alleviate symptoms or serve as a complementary approach alongside conventional medical treatment.

Recommended Dosages

Dosages used in scientific studies vary considerably, but commonly reported ranges include:

• Oregano oil (standardized to 50-85% carvacrol): 200-600 mg daily, divided into 2-3 doses
• Oregano leaf dried herb: 1.5-4.5 g daily
• Oregano tea: 1-2 teaspoons dried herb steeped in hot water, 1-3 times daily
• Essential oil (diluted): 1-3 drops mixed with carrier oil for topical application

Most clinical studies have utilized standardized extracts containing specified amounts of carvacrol and thymol. Commercial products vary widely in composition, and standardization is not consistent across the industry.

Side Effects and Contraindications

Oregano is generally recognized as safe (GRAS) for culinary use, but medicinal doses may cause:

• Gastrointestinal distress (nausea, vomiting, diarrhea)
• Allergic reactions, especially in those with sensitivities to plants in the Lamiaceae family (mint, basil, sage)
• Increased bleeding risk (may interact with anticoagulants)
• Potential interference with some medications due to cytochrome P450 enzyme modulation
• Skin irritation when applied topically (essential oil should always be diluted)

Oregano should be avoided during pregnancy as it may stimulate uterine contractions. It should also be used cautiously in individuals with bleeding disorders or prior to surgery.

High-Dose Studies and Knowledge Gaps

Limited research exists on doses exceeding those listed above. A few toxicity studies in animal models suggest that extremely high doses of oregano essential oil (>100 mg/kg body weight) may cause hepatotoxicity and adverse effects on the central nervous system. However, there remains a significant knowledge gap regarding long-term safety and efficacy of high-dose oregano supplementation in humans.

Research gaps include:

• Long-term safety studies (most are short-term)
• Standardized dosing guidelines
• Drug-herb interaction profiles
• Comparative efficacy between different oregano species and preparations
• Well-designed clinical trials for many claimed benefits

References

Bukovská, A., Čikoš, Š., Juhás, Š., Il’ková, G., Rehák, P., & Koppel, J. (2007). Effects of a combination of thyme and oregano essential oils on TNBS‐induced colitis in mice. Mediators of inflammation, 2007(1), 023296.

de Torre, M. P., Cavero, R. Y., & Calvo, M. I. (2022). Anticholinesterase activity of selected medicinal plants from Navarra region of Spain and a detailed phytochemical investigation of Origanum vulgare L. ssp. vulgare. Molecules, 27(20), 7100.

Lombrea, A., Antal, D., Ardelean, F., Avram, S., Pavel, I. Z., Vlaia, L., ... & Danciu, C. (2020). A recent insight regarding the phytochemistry and bioactivity of Origanum vulgare L. essential oil. International journal of molecular sciences, 21(24), 9653.

Marchese, A., Arciola, C. R., Coppo, E., Barbieri, R., Barreca, D., Chebaibi, S., ... & Daglia, M. (2018). The natural plant compound carvacrol as an antimicrobial and anti-biofilm agent: Mechanisms, synergies and bio-inspired anti-infective materials. Biofouling, 34(6), 630-656.

Rizzello, F., Ricci, C., Scandella, M., Cavazza, E., Giovanardi, E., Valerii, M. C., ... & Spisni, E. (2018). Dietary geraniol ameliorates intestinal dysbiosis and relieves symptoms in irritable bowel syndrome patients: A pilot study. BMC Complementary and Alternative Medicine, 18, 1-11.

Sharifi‐Rad, M., Berkay Yılmaz, Y., Antika, G., Salehi, B., Tumer, T. B., Kulandaisamy Venil, C., ... & Sharifi‐Rad, J. (2021). Phytochemical constituents, biological activities, and health‐promoting effects of the genus Origanum. Phytotherapy Research, 35(1), 95-121.

Stojković, D., Glamočlija, J., Ćirić, A., Nikolić, M., Ristić, M., Šiljegović, J., & Soković, M. (2013). Investigation on antibacterial synergism of Origanum vulgare and Thymus vulgaris essential oils. Archives of biological sciences, 65(2), 639-643.