Choosing the Right Cinnamon: A Spice and a Supplement
The culinary spices collectively known as cinnamon are derived from the fragrant inner bark of a group of small evergreen trees called Cinnamomum. Cinnamon has been used as a culinary and medicinal spice for thousands of years.
Ceylon cinnamon and Cassia cinnamon
The two major types of cinnamon used in food preparation are Ceylon cinnamon and Cassia cinnamon. Ceylon cinnamon (Cinnamomum verum or Cinnamomum zeylanicum), native to Sri Lanka, is also known as “true cinnamon.” This is NOT the predominant spice typically sold as cinnamon in the United States. What is commonly found at your grocer is a closely related and less expensive variety called Cassia cinnamon. Cassia is native to Burma and also grown in China and Vietnam. Cassia is slightly darker in color compared to Ceylon, and has a stronger, more pungent flavor. While both Cassia and Ceylon are derived from the inner bark of Cinnamomum trees, Ceylon cinnamon is preferable. Ceylon cinnamon is considered a finer quality spice due to its sweeter, more delicate and complex flavor.
In addition to flavor, a critical difference between Ceylon and Cassia is the coumarin content of Cassia. Cassia cinnamon is the main source of coumarin in the human diet.1 Coumarin is a naturally occurring toxin which has the potential to damage the liver in high doses. Cassia contains high levels of coumarin, whereas Ceylon contains either undetectable levels or only traces of coumarin.2 Coumarin can cause liver toxicity in several species, and was found to be carcinogenic in rodents.3
Recent studies have revealed that regularly consuming Cassia cinnamon powder could be problematic, resulting in potentially harmful levels of coumarin intake. For example, one study estimated that small children eating oatmeal sprinkled with cinnamon a few times a week would exceed the established safe upper limit of exposure. Similarly, they concluded that adults who are heavy consumers of culinary cinnamon or take powdered cinnamon supplements could also reach potentially unsafe doses.3-5
For food preparation, Ceylon cinnamon is the clear choice for health, quality and flavor. Reflecting these standards, Dr. Fuhrman’s Apple Cinnamon Date Nut Bars and Pop’Ems contain Ceylon cinnamon, and powdered Ceylon cinnamon is available on DrFuhrman.com.
Cinnamon promotes healthy blood glucose levels
Cinnamon is one of the oldest and most widely used natural supplements for reducing blood glucose. The bark of Cinnamomum trees contains phytochemicals that enhance insulin signaling and facilitate glucose uptake and storage by the body’s cells.6-9 Supplemental cinnamon powder and cinnamon extracts have been shown in numerous studies to reduce fasting blood glucose in diabetic individuals.10,11
Cinnamon-containing supplements, such as Glucotect, may be used as an adjunct to a high-nutrient eating style and exercise program as described in Dr. Fuhrman’s book The End of Diabetes, to assist those with diabetes in achieving favorable HbA1C and fasting blood glucose. However, when using such a supplement, always take note of the source of the supplemental cinnamon. Most of the human trials that have demonstrated glucose-balancing effects of cinnamon powder have used Cassia. However, powdered Cassia supplements can expose people to excess coumarin.
Although Ceylon cinnamon is preferable for culinary purposes, it hasn’t been adequately studied in humans for its effects on blood glucose levels.12 Water-soluble cinnamon extracts have also been used in several trials and are effective at lowering blood glucose levels. Since coumarin is fat-soluble, water-soluble cinnamon extracts can maximize the active glucose-lowering cinnamon phytochemicals while minimizing or excluding the coumarin.10 For supplements, cinnamon extracts provide the optimal balance of safety and efficacy.
1. Woehrlin F, Fry H, Abraham K, et al: Quantification of flavoring constituents in cinnamon: high variation of coumarin in cassia bark from the German retail market and in authentic samples from indonesia. J Agric Food Chem 2010, 58:10568-10575.
2. Blahova J, Svobodova Z: Assessment of coumarin levels in ground cinnamon available in the Czech retail market. ScientificWorldJournal 2012, 2012:263851.
3. Fotland TO, Paulsen JE, Sanner T, et al: Risk assessment of coumarin using the bench mark dose (BMD) approach: children in Norway which regularly eat oatmeal porridge with cinnamon may exceed the TDI for coumarin with several folds. Food Chem Toxicol 2012, 50:903-912.
4. Abraham K, Pfister M, Wohrlin F, et al: Relative bioavailability of coumarin from cinnamon and cinnamon-containing foods compared to isolated coumarin: a four-way crossover study in human volunteers. Mol Nutr Food Res 2011, 55:644-653.
5. Abraham K, Wohrlin F, Lindtner O, et al: Toxicology and risk assessment of coumarin: focus on human data. Mol Nutr Food Res 2010, 54:228-239.
6. Nahas R, Moher M: Complementary and alternative medicine for the treatment of type 2 diabetes. Can Fam Physician 2009, 55:591-596.
7. Imparl-Radosevich J, Deas S, Polansky MM, et al: Regulation of PTP-1 and insulin receptor kinase by fractions from cinnamon: implications for cinnamon regulation of insulin signalling. Horm Res 1998, 50:177-182.
8. Jarvill-Taylor KJ, Anderson RA, Graves DJ: A hydroxychalcone derived from cinnamon functions as a mimetic for insulin in 3T3-L1 adipocytes. J Am Coll Nutr 2001, 20:327-336.
9. Anderson RA, Broadhurst CL, Polansky MM, et al: Isolation and characterization of polyphenol type-A polymers from cinnamon with insulin-like biological activity. J Agric Food Chem 2004, 52:65-70.
10. Davis PA, Yokoyama W: Cinnamon intake lowers fasting blood glucose: meta-analysis. J Med Food 2011, 14:884-889.
11. Akilen R, Tsiami A, Devendra D, et al: Cinnamon in glycaemic control: Systematic review and meta analysis. Clin Nutr 2012, 31:609-615.
12. Ranasinghe P, Jayawardana R, Galappaththy P, et al: Efficacy and safety of 'true' cinnamon (Cinnamomum zeylanicum) as a pharmaceutical agent in diabetes: a systematic review and meta-analysis. Diabet Med 2012, 29:1480-1492.