Cinnamon (Cinnamomum zeylanicum, Cinnamomum aromaticum, Cinnamomum loureiroi, Cinnamomum burmannii)
Cinnamon refers to several plants that belong to the genus Cinnamomum, native to Southeast Asia. Cinnamon consists of the dried bark, separated from cork and the underlying parenchyma, of young branches and shoots of species of Cinnamomum. The bark, rich in essential oil, is used as a flavoring agent and as a spice.
Medicinal uses include appetite stimulation, and treatment of type-2 diabetes, arthritis, inflammation, and dyspeptic complaints such as mild, spastic condition of the gastrointestinal tract, bloating, flatulence. In traditional Chinese medicine, cinnamon is used along with other herbs in decoctions to treat infections. Cinnamon is a coagulant and prevents bleeding. Cinnamon also increases blood circulation in the uterus and advances tissue regeneration. This plant plays a vital role as a spice, but its essential oils and other constituents also have important activities, including antimicrobial, antifungal, antioxidant, and antidiabetic.
Cinnamon consists of a variety of resinous compounds, including cinnamaldehyde, cinnamate, cinnamic acid, and numerous essential oils. It is reported that the spicy taste and fragrance are due to the presence of cinnamaldehyde and occur due to the absorption of oxygen. As cinnamon ages, it darkens in color, improving the resinous compounds. The presence of a wide range of essential oils, such as trans-cinnamaldehyde, cinnamyl acetate, eugenol, L-borneol, caryophyllene oxide, b-caryophyllene, L-bornyl acetate, E-nerolidol, α-cubebene, α-terpineol, terpinolene, and α-thujene, has been reported.
In vitro studies suggest that cinnamon has antioxidant, anti-inflammatory, immunomodulatory, antimicrobial, antitumor, and antiestrogenic properties.
Studies in humans have also been conducted. In clinical trials of cinnamon for type 2 diabetes, results are conflicting. Various meta-analyses and a review suggest some improvements in glycemic control with cinnamon and its extracts, but studies had high heterogeneity and larger well-designed trials are needed. Other meta-analyses suggest cinnamon supplementation may reduce blood triglycerides, total cholesterol concentrations, and C-reactive protein levels, but again well-designed studies are needed to confirm these effects.
Other preliminary data suggest cinnamon extracts may decrease insulin resistance in women with polycystic ovary syndrome; improve parameters of metabolic syndrome and reduce dental plaque and gingivitis. Studies involving topical use of a cinnamon ointment suggest it can relieve perineal pain and improve healing of episiotomy incisions in postpartum women.
In a safety study of patients with prediabetes, a water-soluble cinnamon extract did not appear to affect electrocardiographic measures. However, certain cinnamon products are high in coumarin, which can cause hepatotoxicity and interact with other prescription drugs.
Hydroxycinnamaldehyde, a compound present in cinnamon, exerts anti-inflammatory effects by inhibiting NO production via nuclear factor (NF)-kappaB. Cinnamon also inhibits hepatic HMG-CoA reductase activity and reduces blood lipid levels in animals and humans. In another study, methylhydroxychalcone polymer isolated from cinnamon was shown to mimic insulin by activating the insulin receptors.
Cinnamon extract binds to estrogen-receptor beta and has a direct stimulatory effect on bone formation. The n-hexane extract of cinnamon has antiestrogenic activity. In other studies, increased proapoptotic activity with cinnamon extract was attributed to NF-kappaB and AP1 inhibition, while antiangiogenic effects occurred via VEGF inhibition.
Blevins SM, Leyva MJ, Brown J, et al. Effect of cinnamon on glucose and lipid levels in non insulin-dependent type 2 diabetes. Diabetes Care. Sep 2007;30(9):2236-2237.
Chase CK, McQueen CE. Cinnamon in diabetes mellitus. Am J Health Syst Pharm. May 15 2007;64(10):1033-1035.
Davari M, Hashemi R, Mirmiran P, et al. Effects of cinnamon supplementation on expression of systemic inflammation factors, NF-kB and Sirtuin-1 (SIRT1) in type 2 diabetes: a randomized, double blind, and controlled clinical trial. Nutr J. Jan 4 2020;19(1):1.
Davis PA, Yokoyama W. Cinnamon intake lowers fasting blood glucose: meta-analysis. J Med Food. Sep 2011;14(9):884-889.
Dugoua JJ, Seely D, Perri D, et al. From type 2 diabetes to antioxidant activity: a systematic review of the safety and efficacy of common and cassia cinnamon bark. Can J Physiol Pharmacol. Sep 2007;85(9):837-847.
Endo H, Rees TD. Clinical features of cinnamon-induced contact stomatitis. Compend Contin Educ Dent. Jul 2006;27(7):403-409; quiz 410, 421.
Endo H, Rees TD. Cinnamon products as a possible etiologic factor in orofacial granulomatosis. Med Oral Patol Oral Cir Bucal. Oct 2007;12(6):E440-444.
Gupta D, Jain A. Effect of Cinnamon Extract and Chlorhexidine Gluconate (0.2%) on the Clinical Level of Dental Plaque and Gingival Health: A 4-Week, Triple-Blind Randomized Controlled Trial. J Int Acad Periodontol. 2015 Jul;17(3):91-8.
Gupta Jain S, Puri S, Misra A, Gulati S, Mani K. Effect of oral cinnamon intervention on metabolic profile and body composition of Asian Indians with metabolic syndrome: a randomized double -blind control trial. Lipids Health Dis. 2017 Jun 12;16(1):113
Hajimonfarednejad M, Nimrouzi M, Heydari M, Zarshenas MM, Raee MJ, Jahromi BN. Insulin resistance improvement by cinnamon powder in polycystic ovary syndrome: A randomized double-blind placebo controlled clinical trial. Phytother Res. 2018 Feb;32(2):276-283.
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. Aug 2001;20(4):327-336.
Khan A, Safdar M, Ali Khan MM, et al. Cinnamon improves glucose and lipids of people with type 2 diabetes. Diabetes Care. Dec 2003;26(12):3215-3218.
Kim SH, Hyun SH, Choung SY. Antioxidative effects of Cinnamomi cassiae and Rhodiola rosea extracts in liver of diabetic mice. Biofactors. 2006;26(3):209-219.
Koh WS, Yoon SY, Kwon BM, et al. Cinnamaldehyde inhibits lymphocyte proliferation and modulates T-cell differentiation. Int J Immunopharmacol. Nov 1998;20(11):643-660.
Kwon HK, Hwang JS, So JS, et al. Cinnamon extract induces tumor cell death through inhibition of NFkappaB and AP1. BMC Cancer. 2010;10:392.
Lee JS, Jeon SM, Park EM, et al. Cinnamate supplementation enhances hepatic lipid metabolism and antioxidant defense systems in high cholesterol-fed rats. J Med Food. Fall 2003;6(3):183-191.
Lee KH, Choi EM. Stimulatory effects of extract prepared from the bark of Cinnamomum cassia blume on the function of osteoblastic MC3T3-E1 cells. Phytother Res. Nov 2006;20(11):952-960.
Lee SH, Lee SY, Son DJ, et al. Inhibitory effect of 2’-hydroxycinnamaldehyde on nitric oxide production through inhibition of NF-kappa B activation in RAW 264.7 cells. Biochem Pharmacol. Mar 1 2005;69(5):791-799.
Lin CC, Wu SJ, Chang CH, et al. Antioxidant activity of Cinnamomum cassia. Phytother Res. Aug 2003;17(7):726-730.
Lu J, Zhang K, Nam S, et al. Novel angiogenesis inhibitory activity in cinnamon extract blocks VEGFR2 kinase and downstream signaling. Carcinogenesis. Mar 2010;31(3):481-488.
Maierean SM, Serban MC, Sahebkar A, et al. The effects of cinnamon supplementation on blood lipid concentrations: A systematic review and meta-analysis. J Clin Lipidol. 2017 Nov - Dec;11(6):1393-1406.
Mang B, Wolters M, Schmitt B, et al. Effects of a cinnamon extract on plasma glucose, HbA, and serum lipids in diabetes mellitus type 2. Eur J Clin Invest. May 2006;36(5):340-344.
Mirmiran P, Davari M, Hashemi R, et al. A randomized controlled trial to determining the effect of cinnamon on the plasma levels of soluble forms of vascular adhesion molecules in type 2 diabetes mellitus. Eur J Clin Nutr. Dec 2019;73(12):1605-1612.
Mohammadi A, Mohammad-Alizadeh-Charandabi S, Mirghafourvand M, Javadzadeh Y, Fardiazar Z, Effati-Daryani F. Effects of cinnamon on perineal pain and healing of episiotomy: a randomized placebo-controlled trial. J Integr Med. 2014 Jul;12(4):359-66.
Namazi N, Khodamoradi K, Khamechi SP, et al. The impact of cinnamon on anthropometric indices and glycemic status in patients with type 2 diabetes: A systematic review and meta-analysis of clinical trials. Complement Ther Med. Apr 2019;43:92-101.
Pender DN, Crawford PF, Clark JM, et al. Effect of water-soluble cinnamon extract on electrocardiographic parameters: An analysis of the CiNNaMON trial. Complement Ther Med. Dec 2018;41:302-305.
Reddy AM, Seo JH, Ryu SY, et al. Cinnamaldehyde and 2-methoxycinnamaldehyde as NF-kappaB inhibitors from Cinnamomum cassia. Planta Med. Sep 2004;70(9):823-827.
Shahverdi AR, Monsef-Esfahani HR, Tavasoli F, et al. Trans-cinnamaldehyde from Cinnamomum zeylanicum bark essential oil reduces the clindamycin resistance of Clostridium difficile in vitro. J Food Sci. Jan 2007;72(1):S055-058.
Vanschoonbeek K, Thomassen BJ, Senden JM, et al. Cinnamon supplementation does not improve glycemic control in postmenopausal type 2 diabetes patients. J Nutr. Apr 2006;136(4):977-980
Vallianou N, Tsang C, Taghizadeh M, et al. Effect of cinnamon (Cinnamomum zeylanicum) supplementation on serum C-reactive protein concentrations: A meta-analysis and systematic review. Complement Ther Med. Feb 2019;42:271-278.
Zare R, Nadjarzadeh A, Zarshenas MM, Shams M, Heydari M. Efficacy of cinnamon in patients with type II diabetes mellitus: A randomized controlled clinical trial. Clin Nutr. 2019;38:549-556.