Cinnamon  (Cinnamomum verum),

(family Lauraceae), commonly known as cinnamon or Ceylon cinnamon, is a small evergreen tree native to Sri Lanka and southern India. Its inner bark, dried and rolled into quills, produces the high-quality spice known as “true cinnamon,” distinct from Cinnamomum cassia, which is coarser and has a stronger, more pungent flavor.
Cinnamon has been prized since ancient times as a spice, preservative, and natural remedy for its aromatic, digestive, antimicrobial, and tonic properties. Its sweet, warm fragrance is due to volatile compounds found in the essential oil of the bark.

Botanical classification

Kingdom: Plantae
Clade: Angiosperms
Order: Laurales
Family: Lauraceae
Genus: Cinnamomum
Species: C. verum

Plant characteristics

• Habit: Small evergreen tree (8–12 m) with dense foliage and aromatic leaves.

• Leaves: Opposite, oval to elliptical, leathery, glossy, with three prominent parallel veins; light green when young, darker when mature.

• Flowers: Small, yellowish or cream-colored, grouped in axillary or terminal panicles; faintly aromatic.

• Fruits: Oval drupes, dark violet to black when ripe, each containing a single seed.

• Bark: Thin, reddish-brown, smooth; the inner layer is the aromatic portion used as spice.

• Roots: Woody and branching, providing anchorage and storing aromatic oils.

Chemical composition (main constituents of bark and essential oil)

• Essential oil (0.5–1%): cinnamaldehyde (60–70%), eugenol, linalool, benzaldehyde, coumarin (trace amounts in C. verum).

• Tannins: astringent and preservative properties.

• Resins and mucilages: contribute to the aroma and natural preservation.

• Polyphenols and flavonoids: antioxidant and anti-inflammatory actions.

• Coumarins: present only in minimal amounts, making C. verum safer for long-term use than C. cassia.

Cultivation and growing conditions

• Climate: Tropical and humid; optimal temperatures 25–30 °C; frost-sensitive.

• Exposure: Full sun or partial shade; requires good air circulation.

• Soil: Fertile, deep, well-drained, slightly acidic to neutral; thrives in humus-rich soils.

• Propagation: By cuttings or seeds; vegetative propagation preserves aromatic quality.

• Harvesting: Bark collected from young stems every 2–3 years.

• Processing: Inner bark is peeled, dried, and rolled into thin quills.

Uses and benefits (traditional and supported by preliminary scientific evidence)

• Digestive and carminative: Promotes digestion and helps reduce intestinal gas.

• Antimicrobial and antiviral: Essential oil shows activity against bacteria, fungi, and viruses.

• Anti-inflammatory and antioxidant: Helps counter oxidative stress.

• Hypoglycemic and metabolic support: May assist in regulating blood glucose levels.

• Tonic and stimulant: Traditionally used to improve circulation and vitality.

Scientific research supports some of cinnamon’s biological activities, though it should be used as a complementary measure and not as a replacement for medical treatments.

Applications

• Food: Aromatic spice for desserts, beverages, meats, and liqueurs.

• Herbal medicine: Decoctions, dry extracts, and tinctures used as digestive tonics and antimicrobials.

• Cosmetics: Essential oil used in perfumes, lotions, and warming products (in low concentrations).

• Aromatherapy: Stimulating and warming, promotes focus and mood enhancement.

• Pharmaceutical: Natural component in mouthwashes and antibacterial formulations.

Harvesting and processing

• Harvesting: Stems cut every 2–3 years, after the rainy season.

• Preparation: Bark is scored and peeled; the inner layer is dried until it curls naturally.

• Drying: In well-ventilated, shaded areas to preserve aroma and color.

• Storage: In airtight containers, away from moisture and light.

Environmental considerations

Cinnamomum verum cultivation is sustainable when bark is periodically harvested without harming the tree. These trees help stabilize tropical soils and support biodiversity in Sri Lanka’s forests. Distinguishing C. verum from C. cassia is important, as intensive cassia cultivation can have a greater environmental impact.

Safety, contraindications, interactions

Generally regarded as safe at traditional dietary doses.

• Excessive or prolonged use: May cause gastric irritation or allergic reactions.

• Essential oil: Must always be diluted; can irritate skin and mucous membranes.

• Pregnancy and lactation: Moderate culinary use considered safe; concentrated forms should be avoided.

• Drug interactions: May enhance the effects of hypoglycemic or anticoagulant medications.

Common preparations (general, non-therapeutic use)

• Infusion: 1 stick or 1 g of bark in 200 ml boiling water; steep for 10 minutes.

• Decoction: 2 g bark in 200 ml water, boiled for 5 minutes (digestive use).

• Powder: Used as a spice or encapsulated for herbal preparations.

• Essential oil: A few drops in diffusion or diluted in carrier oils (max 0.5%).

Medicine

Cinnamon contains bioactive compounds such as eugenol and cinnamaldehyde that give hypoglycemic, antimicrobial, antifungal, antiviral, antioxidant, anticancer, hypotensive, hypocholesterolemic and gastroprotective properties. In vitro and in vivo studies indicate that cinnamon can have multiple health benefits, mainly in relation to hypoglycemic activity. Other research has shown potential antidiabetic, anti-inflammatory and antilipidemic effects.

Studies

The bark of this plant is used to make spice cinnamon and has long been used as a traditional Chinese herbal medicine for various pathological conditions (1).

Previous studies have identified Cinnamon extract as a potential treatment for benign prostate hyperplasia (2) and some types of cancers (3).

Studies have shown that cinnamon has also been used traditionally in age-related brain disorders (4).

Useful components of Cinnamon's essential oil include transcinnamaldehyde (72.81%), benzilic alcohol (12.5%) eugenolity (6.57%) (5).

Cinnamon studies

References__________________________________________________

(1) Yang SM, Tsai KD, Wong HY, Liu YH, Chen TW, Cherng J, Hsu KC, Ang YU, Cherng JM. Molecular Mechanism of Cinnamomum verum Component Cuminaldehyde Inhibits Cell Growth and Induces Cell Death in Human Lung Squamous Cell Carcinoma NCI-H520 Cells In Vitro and In Vivo. J Cancer. 2016 Jan 5;7(3):251-61. doi: 10.7150/jca.13689. PMID: 26918037; PMCID: PMC4747878.

Abstract. Cinnamomum verum is used to make the spice cinnamon and has been used as a traditional Chinese herbal medicine. We evaluated the effects and the molecular mechanisms of cuminaldehyde (CuA), a constituent of the bark of Cinnamomum verum, on human lung squamous cell carcinoma NCI-H520 cells. Specifically, cell viability was evaluated by colorimetric assay; cytotoxicity by LDH release; apoptosis was determined by Western blotting, and morphological analysis with, acridine orange and neutral red stainings and comet assay; topoisomerase I activity was assessed using assay based upon DNA relaxation and topoisomerase II by DNA relaxation plus decatentation of kinetoplast DNA; lysosomal vacuolation and volume of acidic compartments (VAC) were evaluated with neutral red staining. The results show that CuA suppressed proliferation and induced apoptosis as indicated by an up-regulation of pro-apoptotic bax and bak genes and a down-regulation of anti-apoptotic bcl-2 and bcl-XL genes, mitochondrial membrane potential loss, cytochrome c release, activation of caspase 3 and 9, and morphological characteristics of apoptosis, including blebbing of the plasma membrane, nuclear condensation, fragmentation, apoptotic body formation, and comet with elevated tail intensity and moment. In addition, CuA also induced lysosomal vacuolation with increased VAC, cytotoxicity, as well as suppressions of both topoisomerase I and II activities in a dose-dependent manner. Further study revealed the growth-inhibitory effect of CuA was also evident in a nude mice model. Taken together, the data suggest that the growth-inhibitory effect of CuA against NCI-H520 cells is accompanied by downregulations of proliferative control involving apoptosis and both topoisomerase I and II activities, and upregulation of lysosomal with increased VAC and cytotoxicity. Similar effects were found in other cell lines, including human lung adenocarcinoma A549 cells and colorectal adenocarcinoma COLO 205 (results not shown). Our data suggest that CuA could be a potential agent for anticancer therapy.

(2) Choi HM, Jung Y, Park J, Kim HL, Youn DH, Kang J, Jeong MY, Lee JH, Yang WM, Lee SG, Ahn KS, Um JY. Cinnamomi Cortex (Cinnamomum verum) Suppresses Testosterone-induced Benign Prostatic Hyperplasia by Regulating 5α-reductase. Sci Rep. 2016 Aug 23;6:31906. doi: 10.1038/srep31906. 

Abstract. Cinnamomi cortex (dried bark of Cinnamomum verum) is an important drug in Traditional Korean Medicine used to improve blood circulation and Yang Qi. Benign prostatic hyperplasia (BPH) is a common chronic disease in aging men. This study was conducted to determine the effect of Cinnamomi cortex water extract (CC) on BPH. BPH was induced by a pre-4-week daily injection of testosterone propionate (TP). Six weeks of further injection with (a) vehicle, (b) TP, (c) TP + CC, (d) TP + finasteride (Fi) was carried on. As a result, the prostate weight and prostatic index of the CC treatment group were reduced. Histological changes including epithelial thickness and lumen area were recovered as normal by CC treatment. The protein expressions of prostate specific antigen, estrogen receptor α (ERα), androgen receptor (AR), 5α-reductase (5AR), and steroid receptor coactivator 1 were suppressed by treatment of CC. Immunohistochemical assays supported the western blot results, as the expressions of AR and ERα were down-regulated by CC treatment as well. Further in vitro experiments showed CC was able to inhibit proliferation of RWPE-1 cells by suppressing 5AR and AR. These results all together suggest CC as a potential treatment for BPH.

 (3) Perng DS, Tsai YH, Cherng J, Wang JS, Chou KS, Shih CW, Cherng JM. Discovery of a novel anticancer agent with both anti-topoisomerase I and II activities in hepatocellular carcinoma SK-Hep-1 cells in vitro and in vivo: Cinnamomum verum component 2-methoxycinnamaldehyde. Drug Des Devel Ther. 2016 Jan 5;10:141-53. doi: 10.2147/DDDT.S93599. 

Abstract. Cinnamomum verum is used to make the spice cinnamon and has been used as a traditional Chinese herbal medicine for various applications. We evaluated the anticancer effect of 2-methoxycinnamaldehyde (2-MCA), a constituent of the bark of the plant, and its underlying molecular biomarkers associated with carcinogenesis in human hepatocellular carcinoma SK-Hep-1 cell line. The results show that 2-MCA suppressed proliferation and induced apoptosis as indicated by mitochondrial membrane potential loss, activation of caspase-3 and caspase-9, increase in the DNA content in sub-G1, and morphological characteristics of apoptosis, including blebbing of plasma membrane, nuclear condensation, fragmentation, apoptotic body formation, and long comet tail. In addition, 2-MCA also induced lysosomal vacuolation with increased volume of acidic compartments, suppressions of nuclear transcription factors NF-κB, cyclooxygenase-2, prostaglandin E2 (PGE2), and both topoisomerase I and II activities in a dose-dependent manner. Further study reveals the growth-inhibitory effect of 2-MCA was also evident in a nude mice model. Taken together, the data suggest that the growth-inhibitory effect of 2-MCA against SK-Hep-1 cells is accompanied by downregulations of NF-κB-binding activity, inflammatory responses involving cyclooxygenase-2 and PGE2, and proliferative control involving apoptosis, both topoisomerase I and II activities, together with an upregulation of lysosomal vacuolation and volume of acidic compartments. Similar effects (including all of the above-mentioned effects) were found in other tested cell lines, including human hepatocellular carcinoma Hep 3B, lung adenocarcinoma A549, squamous cell carcinoma NCI-H520, colorectal adenocarcinoma COLO 205, and T-lymphoblastic MOLT-3 (results not shown). Our data suggest that 2-MCA could be a potential agent for anticancer therapy.

(4) Peterson DW, George RC, Scaramozzino F, LaPointe NE, Anderson RA, Graves DJ, Lew J. Cinnamon extract inhibits tau aggregation associated with Alzheimer's disease in vitro. J Alzheimers Dis. 2009;17(3):585-97. doi: 10.3233/JAD-2009-1083. 

Abstract. An aqueous extract of Ceylon cinnamon (C. zeylanicum) is found to inhibit tau aggregation and filament formation, hallmarks of Alzheimer's disease (AD). The extract can also promote complete disassembly of recombinant tau filaments and cause substantial alteration of the morphology of paired-helical filaments isolated from AD brain. Cinnamon extract (CE) was not deleterious to the normal cellular function of tau, namely the assembly of free tubulin into microtubules. An A-linked proanthocyanidin trimer molecule was purified from the extract and shown to contain a significant proportion of the inhibitory activity. Treatment with polyvinylpyrolidone effectively depleted all proanthocyanidins from the extract solution and removed the majority, but not all, of the inhibitory activity. The remainder inhibitory activity could be attributed to cinnamaldehyde. This work shows that compounds endogenous to cinnamon may be beneficial to AD themselves or may guide the discovery of other potential therapeutics if their mechanisms of action can be discerned.

(5) Yap PS, Krishnan T, Chan KG, Lim SH. Antibacterial Mode of Action of Cinnamomum verum Bark Essential Oil, Alone and in Combination with Piperacillin, Against a Multi-Drug-Resistant Escherichia coli Strain. J Microbiol Biotechnol. 2015 Aug;25(8):1299-306. doi: 10.4014/jmb.1407.07054.