The bark of the cinnamon tree is a popular spice that has been used in cooking and medicine since around 3000 BC. True cinnamon (Cinnamomum zeylanicum) is usually wild-harvested and the spice is obtained from the dried inner bark of the shoots. Commercial cinnamon may be obtained from one of several species other than zeylanicum such as cassia/ aromaticum (China), burmannii (Indonesia), loureiroi (Vietnam), verum (Sri Lanka), citriodorum (Malabar) and tamale (India).

The main active constituents are cinnamaldehyde, trans-cinnamaldehyde, cinnamate and eugenol which are mostly present in the essential oil, contributing to the fragrance as well as cinnamon’s biological activity. The bark also contains procyanidins and catechins which possess antioxidant activity, while the whole plant has antimicrobial, antidiabetic, antiinflammatory, insecticidal, antimycotic and anticancer activity.[i]

The methanol extract of cinnamon has the maximum antioxidant activity, but ethanol and water extracts also possess good activity. The constituent eugenol is of particular interest in preventing lipid oxidation while markers for inflammation are reduced in laboratory studies.[ii]

Cinnamon has long been used to treat blood sugar problems. Extracts enhance insulin sensitivity, insulin disposal, regulate insulin receptor sensitivity, and improve both lipid and glucose metabolism. In rat experiments, insulin resistance can be induced using a diet rich in factory fats and fructose, resembling our modern urban diet, which induces changes in the rat’s mRNA. Interestingly, this is also consistent with the gene alterations seen in Alzheimer’s disease. Cinnamon not only reduces the insulin resistance observed in these lab rats, but demonstrates neuro-protective effects including favourable alterations in Tau and amyloid precursor protein.[iii]

A recent meta-analysis has compared cinnamon’s pharmacological activity with several conventional medicines: it was found that the reduction in fasting plasma glucose levels achieved by cinnamon are about half of those achieved by the drug metformin, but more than the newer drugs such as sitagliptin. Cinnamon also reduces LDL cholesterol by a fifth of that achieved by pravastatin and gemfibrozil, and reduces triglycerides by slightly more than both these drugs.[iv]

These findings demonstrate that cinnamon is a very effective alternative medicine for the treatment of several metabolic diseases, especially when combined with a nutrient-dense wholefood diet and regular exercise. In terms of heart health alone, cinnamon not only lowers blood lipids, but also increases circulation by inducing vasodilation, and therefore can be used to lower blood pressure.[v]

Cancer is another common degenerative disease of modern civilisation, and cancer cells can remain dormant for many years due to a balance between proliferation and cell death (apoptosis). Proliferation relies on the ability of tumour cells to increase their blood supply and anticancer agents are being developed to inhibit this process in order to starve them. Cinnamon also contains a very high level of procyanidins which have been found  to inhibit cancer cell proliferation in vitro; inhibit melanoma growth in mouse trials; and suppress vascular endothelial growth factor, an important step in angiogenesis.[vi]

In addition to this broad profile of activity that can help combat the development of common metabolic disorders, cinnamon possesses significant antimicrobial activity against a wide number of bacteria including Clostridium difficile, Enterobacter aerogenes, Escherichia coli, Helicobacter pylori, Klebsiella pneumonia, Listeria ivanovii, Mycobacterium tuberculosis, Staphylococcus aureus and Streptococcus pneumoniae. It is also antifungal in activity, making cinnamon a useful treatment against Candida albicans.[vii]

[i] Rao & Gan. Cinnamon: A Multifaceted Medicinal Plant. Hindawi Publishing Corporation Evidence-Based Complementary and Alternative Medicine, Volume 2014.

[ii] Kawatra & Rajagopalan. Cinnamon: Mystic powers of a minute ingredient. Pharmacognosy Res. 2015 Jun; 7 (Suppl 1): S1–S6.

[iii] Anderson et al. Cinnamon Counteracts the Negative Effects of a High Fat/ High Fructose Diet on Behavior, Brain Insulin Signaling and Alzheimer-Associated Changes. PLOS ONE December 2013, vol 8, issue 12.

[iv] Allan & Schwartzman. Cinnamon Use in Type 2 Diabetes: An Updated  Systematic Review and Meta-Analysis. Ann Fam Med, 2013; 452-459.

[v] Ranasinghe et al. Medicinal properties of ‘true’ cinnamon (Cinnamomum zeylanicum): a systematic review. BMC Complement Altern Med. 2013; 13: 275.

[vi] Lu et al. Novel angiogenesis inhibitory activity in cinnamon extract blocks VEGFR2 kinase and downstream signaling. Carcinogenesis. 2010 Mar; 31(3): 481–488.

[vii] Ranasinghe et al. Medicinal properties of ‘true’ cinnamon (Cinnamomum zeylanicum): a systematic review. BMC Complement Altern Med. 2013; 13: 275.