Understanding the Difference: Leaves vs. Essential Oil
The most important distinction for anyone considering ingesting lemon myrtle is the form in which it is consumed. The leaves, whether fresh or dried and ground into a powder, are widely used and safe for culinary purposes. The highly concentrated essential oil, however, is a very different product meant for topical or aromatic use and is not safe to be taken internally. Confusing the two can have severe health consequences.
Culinary Use: Safe and Flavorful
Lemon myrtle leaves, often dried and milled, are a popular Australian native food that has found its way into commercial kitchens and home pantries worldwide. They offer a distinctive, vibrant citrus flavor that is often described as a more intense version of lemon, lime, and lemongrass combined. When used correctly, they are a safe and delicious ingredient.
How to Safely Use Lemon Myrtle Leaves
- Herbal Tea: Infusing dried or fresh lemon myrtle leaves in hot water is a simple and common way to enjoy its flavour and potential antioxidant benefits.
- Seasoning: The dried, crushed leaves can be used to flavor a wide range of savoury dishes, including roasted chicken, fish, and various rice or vegetable recipes.
- Baking and Desserts: Lemon myrtle leaf powder is a fantastic addition to baked goods like biscuits, cakes, and cheesecakes, and can also be used to flavor custards and ice-cream. Its low acidity compared to lemon juice makes it a perfect ingredient for dairy-based desserts without causing curdling.
Essential Oil: A Dangerous Concentration
Lemon myrtle essential oil contains a high concentration of citral, often exceeding 90%. While this compound contributes to its pleasant fragrance and potent antimicrobial properties, it also makes the oil toxic if ingested, with safety data sheets explicitly stating not to swallow the product.
Warning: Do not consume lemon myrtle essential oil under any circumstances.
Scientific studies have demonstrated the cytotoxic effects of concentrated lemon myrtle oil on human cell lines, indicating its unsuitability for internal use. Ingesting essential oils can cause severe internal damage, and side effects can include nausea, vomiting, and lung failure, especially in concentrated amounts. For this reason, the essential oil should only be used topically (when properly diluted) or aromatically.
Important Safety Precautions
Beyond distinguishing between the leaf and essential oil, several other precautions must be taken to ensure safe use of lemon myrtle.
Pregnancy and Lactation
Information regarding the safety of lemon myrtle for pregnant and breastfeeding women is currently insufficient. Some sources advise caution, particularly with high-citral essential oils, due to potential risks to fetal development. Medical professionals and governing bodies recommend exercising caution with any form of lemon myrtle during these periods.
Allergic Reactions and Skin Sensitivity
Some individuals may have a skin sensitivity or allergy to citral. While this is primarily a concern for topical application of the essential oil, it is prudent for anyone with known citral allergies to be cautious with all forms. An allergic skin reaction or rash is a potential adverse effect.
Lemon Myrtle vs. Common Myrtle
It is vital to distinguish between Backhousia citriodora (Lemon Myrtle) and Myrtus communis (Common Myrtle). The oil from Common Myrtle is considered unsafe for ingestion and has been associated with serious side effects. Always ensure you are using the correct product and not confusing the two different plants.
Comparison Table: Leaf vs. Essential Oil
| Feature | Lemon Myrtle Leaf | Lemon Myrtle Essential Oil |
|---|---|---|
| Ingestion | Generally safe for culinary use in moderate amounts. | Extremely toxic and unsafe for ingestion. |
| Concentration | Low concentration of volatile oils and citral. | Highly concentrated with 90%+ citral. |
| Applications | Tea, baking, savoury dishes, seasoning. | Topical antimicrobial products (diluted), aromatherapy, cleaning. |
| Safety Warning | No significant side effects noted with moderate intake. | Can cause severe irritation, skin sensitization, and internal toxicity. |
| Regulation | FDA GRAS status for citral flavorings. | Requires warnings for irritant properties and restricted use. |
Conclusion: Safe in Culinary Form, Dangerous as an Oil
In conclusion, the safety of ingesting lemon myrtle hinges entirely on the form in which it is used. Consuming the leaves, whether fresh, dried, or ground, is a time-honoured and generally safe practice for adding a unique citrus flavor to foods and beverages. However, lemon myrtle essential oil is a powerful, concentrated substance that is toxic when ingested and should never be consumed internally. Always use essential oil products as intended for topical or aromatic use, and only with proper dilution. Pregnant women, those who are breastfeeding, and individuals with allergies should exercise additional caution and consult a healthcare provider before use. By understanding these critical distinctions, you can safely enjoy the culinary benefits of this remarkable native Australian plant.
For more information on the toxicology of lemon myrtle essential oil, consult research from credible sources like the National Institutes of Health.
