*For a general introduction to terpenes as a whole, check out The Dirt on Terpenes.
Limonene is a highly fragrant terpene found in the peels of oranges and other citrus fruits – it comprises 97% of the essential oils found in orange rinds. It’s also present in many plants (eg. mint, celery root, fennel, dill, and caraway) and trees (juniper, red and silver maple, spruce, Douglas Firs). Limonene is commonly added to foods for its lemony flavor, and is used in cosmetics, insect repellants, and cleaning supplies, accessing its natural antibacterial and antimicrobial properties. It also has a home in aromatherapy circles as an uplifting, stress-reducing, and energizing scented oil.
Limonene in the Lab
Because it is one of the most common terpenes found in nature (as well as in cannabis), it has received a lot of scientific attention for a slew of potential medical properties.
In mice studies, D-limonene, the main chemical form of limonene, has demonstrated anti-inflammatory properties and a reduction in fatty liver issues in obese subjects. Another study using D-limonene showed a significant lowering of blood pressure in stroke-prone rats
More than one study has shown limonene to have anti-cancer properties in animals, and early studies also suggest it has an antitumorigenic effect on skin cancer in humans and breast cancer in both animals and humans.
Limonene also shows promise in treating symptoms of anxiety and depression, both when delivered orally and inhaled, by affecting dopamine and seratonin levels in the brain.
Where to find Limonene
You might think that strains that smell like lemon are a safe bet when seeking out limonene, but that strong citrus scent is not always present in limonene-rich strains, and Leafly has talked about the fact that a lemon-named strain like Lemon Meringue does not always have high amounts of limonene. A few of the more common strains that are known to be high in this terpene are Banana OG, Dosidos, MAC, Strawberry Banana, and Wedding Cake.