Cassia cinnamon: Difference between revisions

| common_names        = Cassia cinnamon, Chinese cinnamon, cassia, gui (Chinese, the generic name), rou gui (Chinese, the bark), gui zhi (Chinese, the twig), dar-cini (Persian and Urdu, shared with Ceylon), qirfa (Arabic, shared with Ceylon); the synonymic binomial Cinnamomum aromaticum Nees appears in some older literature

| native_range        = southern China and northern Vietnam (Guangxi and Guangdong provinces are the principal historical and modern production areas); cultivated widely throughout southeast Asia, with related Cinnamomum loureirii (Saigon cinnamon, Vietnam) and Cinnamomum burmannii (Indonesian cinnamon, Java and Sumatra) frequently traded under the generic "cassia" or "cinnamon" name and supplying the majority of American grocery-store cinnamon

| cultivars            = grade-based: Vietnamese cassia (C. loureirii, technically a distinct species) is often the highest-cinnamaldehyde and most pungent product; Chinese cassia (C. cassia proper) is the traditional TCM source; Indonesian cassia (C. burmannii, also a distinct species, also frequently sold as "cassia") is the lower-priced commodity cinnamon dominating American retail. The species distinctions matter for coumarin content (which varies among the three) and for cinnamaldehyde concentration, but the three are routinely sold interchangeably under the "cassia" or "cinnamon" name in the American market

| parts_used          = inner bark (rou gui, the TCM and culinary form, the characteristic hollow tube quill); young twig (gui zhi, the TCM surface-resolving form); the leaf is less used than in C. verum; root bark, camphor-rich, used historically

| intro                = '''Cassia cinnamon''' is the dried inner bark of Cinnamomum cassia (L.) J.Presl, a subtropical evergreen tree of the Lauraceae native to southern China and northern Vietnam and one of the foundational warming herbs of traditional Chinese medicine. The species is the cinnamon of the East Asian materia medica, the principal "cinnamon" of the American supermarket and of commercial baked goods, and the higher-coumarin twin of the Ceylon cinnamon ([[Ceylon cinnamon|Cinnamomum verum]]) with which it is routinely confused in commerce and clinical conversation. Cassia bark is documented in Chinese sources from the Han dynasty onward and appears in the foundational Chinese materia medica the Shennong Bencao Jing (compiled in the early centuries of the common era from older oral tradition) under the entry gui, which is the generic Chinese name for the cinnamon-family barks and twigs. The two principal TCM preparations of the bark are '''rou gui''' (the older, thick, ground-floor bark used as the chief warming-yang herb of the Chinese pharmacopoeia, indicated for kidney-yang deficiency, mingmen-fire weakness, and cold-pattern lumbar and abdominal pain) and '''gui zhi''' (the young twig used in surface-resolving formulas for early-stage external wind-cold patterns); the two are distinct in clinical use within TCM despite arising from the same plant. The cassia of Western commerce and clinical research is most often the bark, marketed under the generic "cinnamon" or "cassia" name without species discrimination from the related Cinnamomum loureirii (Saigon cinnamon, Vietnam) and Cinnamomum burmannii (Indonesian cinnamon, Java), both of which are botanically distinct species but commercially interchangeable with C. cassia in the modern global cinnamon supply. The principal safety distinction from Ceylon cinnamon is the coumarin content: cassia bark contains 0.4 to 4 percent coumarin by dry weight, against trace amounts in Ceylon, and chronic high dietary intake of cassia (heavy supplementation, large cinnamon-rich baked-goods consumption, or social-media "cinnamon challenge" levels) can exceed the European Food Safety Authority tolerable daily intake of 0.1 mg per kg body weight and produce hepatotoxicity in susceptible individuals.

The European reception of cassia was the inverse of the Ceylon trade in scale and clinical prestige. Cassia was the cheaper alternative throughout the medieval and early modern European pharmacopoeial tradition; the Continental tradition (German, French, Dutch) more often accepted cassia where the British tradition preferred Ceylon. The American market, which developed in the nineteenth century outside the British colonial trade network for Ceylon, settled on cassia as the dominant cinnamon for both culinary and clinical use, and the modern American grocery-store "cinnamon" is overwhelmingly C. cassia or one of its related species (C. loureirii, C. burmannii) rather than C. verum.

The modern Western pharmacopoeial tradition recognizes cassia cinnamon (Cinnamomi cassiae cortex) separately from Ceylon, with the coumarin content as the principal safety distinction. The European Medicines Agency Committee on Herbal Medicinal Products issued a separate monograph for Cinnamomum cassia bark, with a specific coumarin-intake warning that the verum monograph does not carry.<ref name="ema-hmpc-cassia">European Medicines Agency, Committee on Herbal Medicinal Products. Community herbal monograph on ''Cinnamomum cassia'' Blume, cortex. EMA/HMPC/513617/2010 (the monograph documents are available from the EMA website).</ref> The German Federal Institute for Risk Assessment issued a 2012 statement on coumarin in cinnamon foods, noting that the EFSA tolerable daily intake of 0.1 mg coumarin per kg body weight is regularly exceeded by chronic high consumption of cassia-containing foods (heavy use of powdered cinnamon in oatmeal and baked goods, supplement use) and recommending Ceylon as the safer choice for chronic high-intake users.<ref name="bfr-coumarin">Bundesinstitut für Risikobewertung (German Federal Institute for Risk Assessment). ''Updated Health Assessment of Coumarin in Cinnamon and Other Foods''. BfR Opinion No 036/2006 (18 September 2006), with subsequent updates including the 2012 communication. Available from the BfR website.</ref> A small literature of case reports documents hepatotoxicity from chronic high-dose cassia supplementation in susceptible individuals, with onset typically over weeks to months of multi-gram daily intake and resolution on discontinuation; the reports are rare in absolute terms relative to the magnitude of cassia consumption worldwide, but the case-report literature is reproducible enough to constitute a real safety signal and is the empirical basis for the EMA and BfR coumarin warnings.<ref name="brancheau-2015">Brancheau D, Patel B, Zughaib M. Do cinnamon supplements cause acute hepatitis? ''The American Journal of Case Reports''. 2015 Apr 29;16:250-254. PMID 25923145.</ref>

| botany              = Cinnamomum cassia is a subtropical evergreen tree of the Lauraceae reaching 10 to 15 m at full size in undisturbed cultivation, maintained as coppice in commercial bark production. The leaves are opposite, oblong to elliptic, 10 to 18 cm long, with five (occasionally three) prominent palmate-pinnate veins running from the base to near the leaf apex; the five-vein pattern is one of the diagnostic distinctions from C. verum, which characteristically has three (occasionally five). The bark of mature trunks is grey-brown, deeply fissured; the medicinally used bark is the harder, thicker inner bark of coppice shoots, scraped of the outer corky layer and dried to form the characteristic single-layer thick rigid quill (a hollow tube rather than the multi-layered brittle scroll of Ceylon). The bark color is darker reddish-brown than the light tan of Ceylon. The flowers are small, greenish-yellow, in lax panicles; the fruit is a small drupe 1 to 2 cm long. The young twigs (gui zhi in TCM preparation) are slender, brown, and cinnamaldehyde-aromatic. Distinguished from Cinnamomum verum in whole-stick or whole-leaf material by the five-vs-three leaf venation, the single-layer-vs-multi-layer quill structure, the darker red-brown color, and the harder rigid texture; these distinctions hold for whole material and are lost in ground powder, where chemical or spectroscopic distinction (cinnamaldehyde-eugenol-coumarin ratio profiling) is required. Distinguished from Cinnamomum loureirii (Saigon cinnamon, the related Vietnamese species often sold interchangeably) by smaller leaf size and somewhat lower cinnamaldehyde content; from Cinnamomum burmannii (Indonesian cinnamon, the principal cassia of the American grocery supply) by leaf morphology and a different terpene profile.

The non-volatile fraction includes '''proanthocyanidins''' (the type A doubly-linked oligomers characteristic of Cinnamomum, contributing to antioxidant and astringent activity), '''MHCP''' (methylhydroxychalcone polymer, identified at higher concentrations in cassia than in Ceylon and proposed as the principal insulin-mimetic constituent), and a range of cinnamic acid derivatives.

| counseling          = The most important counseling distinction for cinnamon is the species, and patients seeking cinnamon for chronic high-intake therapeutic use should generally choose Ceylon ([[Ceylon cinnamon]]) rather than cassia because of the coumarin-content difference. The cinnamon sold as a culinary spice in most American grocery stores and used in commercial baked goods is C. cassia or one of its related species (C. loureirii Saigon cinnamon, C. burmannii Indonesian cinnamon), not C. verum Ceylon cinnamon. The visual distinction between cassia and Ceylon is possible with whole sticks but lost in ground powder. Cassia is darker reddish-brown, composed of a single thick rigid layer rolled into a hollow tube, hard and resistant to crushing, with a strong, simple, pungent aroma; Ceylon is light tan, composed of many thin papery layers tightly rolled into a multi-quill scroll, brittle and easily crushed, with a delicate, complex, sweet aroma.

| seealso              = [[Ceylon cinnamon]], [[Cinnamomum verum]], [[Ginger]], [[Turmeric]], [[Cardamom]], [[Cloves]], [[Star anise]], [[Garlic]]