Ceylon Cinnamon aka 'True Cinnamon
Cinnamon is one of the most commonly used spices in the world, being valued for both its flavor and medicinal properties [1][2]. The ground cinnamon available for consumers to purchase enters production as the cinnamon trees belonging to the Lauraceae family. The species of this tree used to produce the spice are Cinnamomum Cassia (Cassia cinnamon), Cinnamomum Loureiroi (Saigon cinnamon), Cinnamomum Burmannii (Indonesian cinnamon) and Cinnamomum Zeylanicum; the latter is commonly called Ceylon cinnamon [3][1]. Cinnamon spice is produced from the inner bark of these tropical trees and has been used by many cultures for centuries. In Ayurvedic medicine, it has been traditionally used to treat respiratory, digestive and gynecological illnesses [2].
As every part of the cinnamon plant is used and each part has different chemical properties, the medicinal uses for cinnamon are widely varied. The most significant components for therapeutic use are vital oils and derivatives such as cinnamaldehyde, cinnamon acid and cinnamate. These compounds have shown strong antioxidant activity in recent studies, suggesting that they may be able to respond to free radicals in the body and reduce damage from metabolic diseases [1].
Image: Molecular structure of Cinnamaldehyde [1].
Another substance found in cinnamon has been named ‘insulin-potentiating factor’ (IPF) due to it’s ability to lower blood glucose and cholesterol in people with diabetes. The concentration of IPF in cinnamon has been measured as up to 20 times higher than in other spices [1], which may explain why it has been shown to measurably enhance insulin secretion in these groups of people.
Cinnamon oils are also naturally antimicrobial, having an inhibitory effect on various bacteria, fungal and yeast species. The combination of cinnamon with other spices is effective against both gram-positive organisms (such as staph bacteria) and gram-negative ones (such as salmonella and E.coli) [1].
However, there are significant differences between the different varieties of cinnamon. Ceylon Cinnamon is commonly called ‘True Cinnamon’ and is the most expensive type to buy as a spice. The other species such as Cassia, Saigon and Indonesian cinnamon are also sold under the name ‘Cinnamon’ in the US [3] and are cheaper, making them popular sources for brands selling or using this spice in large amounts. In fact, more than 90% of cinnamon imported to the US between 2007-2012 was actually Indonesian cinnamon. Ceylon cinnamon is a small tree native to Sri Lanka and southern parts of India. Its bark is mainly composed of three essential oils named trans-cinnamaldehyde, eugenol and linalool [2]. Importantly, this ‘True’ cinnamon contains low concentrations of a compound named coumarin.
Coumarins are phytochemicals with strong anticoagulant, carcinogenic and hepato-toxic effects [2]. Its use as an additive in food is banned in the US due to its side effects, but naturally occurring coumarin is not regulated [3]. It was initially banned by the FDA as an additive after it was shown to be toxic to the liver in animal models, and later studies indicated that tumors may develop in animals exposed to it for long periods. The European limit for coumarin in foods and drinks was set to 2mg/kg in 1988, and later a tolerable daily intake was set to 0.1mg per kilogram of bodyweight [3]. Later studies showed that the metabolism of coumarin in humans is different from that of rodents and does not generally produce toxic compounds in the liver, but some groups of people within populations are more vulnerable to this. In 2008, the European maximum level of coumarin in cinnamon-flavored baked goods was raised to 50mg/kg. One more recent study analyzed various samples of foods bought from grocery stores and found coumarin to be present in all cinnamon-flavored products. One sample of instant oatmeal from a local store contained 2.4mg per 43g serving [3].
Ceylon cinnamon is the only variety with very low concentrations of coumarin; the levels in cassia cinnamon are between 2.1-4.4g per kilogram of powder. This means that one teaspoon of cassia cinnamon contains between 5.8-12.1mg of coumarin: more than the Tolerable Daily Intake for many consumers [2]. Ceylon cinnamon’s higher price is therefore reflected in its safer, more beneficial properties.
Systematic reviews have been carried out on the effects of Ceylon cinnamon extracts on diabetes, finding many positive effects on animal models. It may reduce glucose absorption in the intestine after a meal, which stimulates the metabolism of glucose already in the bloodstream and synthesis of glycogen [4]. These effects cause insulin to be released, which may benefit those with type-2 diabetes. Extracts of Ceylon cinnamon have also been shown to cause a significant drop in blood pressure in hypertensive rats after intravenous administration. The authors of this study suggest that this may mean that this variety could be useful in human diseases such as hypertension and diabetes, where blood pressure is often increased [4]. Aqueous extracts of Ceylon cinnamon may even inhibit the hallmarks of Alzheimer’s disease development: cluster formation of a protein called tau and filament formation. These structural changes in the brain are intrinsically linked to the disease development, yet this cinnamon extract may even promote disassembly of these tau clusters without negatively affecting the normal function of tau [4].
The two main varieties of cinnamon found in spice jars and in store-bought foods are Ceylon and Cassia, often nicknamed ‘true’ and ‘false’ cinnamon. True cinnamon has a smoother, sweeter flavor and a more distinctive ‘cinnamon’ aroma. These properties, coupled with its more beneficial health benefits, give Ceylon cinnamon a higher price.
A few scientific methods exist to differentiate true and false cinnamon, including microscopic analysis, liquid chromatography and infrared spectroscopy [5]. These methods are accurate and reliable, but expensive, time-consuming and require specialist equipment. Those with a good knowledge of the appearance of cinnamon can differentiate the two types, although this is not possible with ground spices and is vulnerable to human error. True cinnamon has a lighter brown color and the quills of the stick are more tightly rolled than false cinnamon. Cassia cinnamon sticks have a darker, coarser outer appearance and are more loosely rolled [6]. Look for these visual differences if buying whole cinnamon sticks, and when buying ground cinnamon search for reliable, high-quality sources.
Image: The cinnamon on the left is the coarser Cassia cinnamon. The cinnamon on the right is Ceylon cinnamon [6].
Resources:
[1] Rao, P.V. and Gan, S.H., 2014. Cinnamon: a multifaceted medicinal plant. Evidence-Based Complementary and Alternative Medicine, 2014.
[2] Ranasinghe, P., Pigera, S., Premakumara, G.S., Galappaththy, P., Constantine, G.R. and Katulanda, P., 2013. Medicinal properties of ‘true’cinnamon (Cinnamomum zeylanicum): a systematic review. BMC complementary and alternative medicine, 13(1), pp.1-10.
[3] Wang, Y.H., Avula, B., Nanayakkara, N.D., Zhao, J. and Khan, I.A., 2013. Cassia cinnamon as a source of coumarin in cinnamon-flavored food and food supplements in the United States. Journal of agricultural and food chemistry, 61(18), pp.4470-4476.
[4] Ranasinghe, P. and Galappaththy, P., 2016. Health benefits of Ceylon cinnamon (Cinnamomum zeylanicum): a summary of the current evidence. Ceylon Medical Journal, 61(1).
[5] Lopes, J.D.S., de Lima, A.B.S., da Cruz Cangussu, R.R., da Silva, M.V., Ferrão, S.P.B. and Santos, L.S., 2022. Application of spectroscopic techniques and chemometric methods to differentiate between true cinnamon and false cinnamon. Food Chemistry, 368, p.130746.
[6] Forsberg, A., spice trade. https://herbsocietyblog.wordpress.com/tag/spice-trade/