Listed under “Herbs that release the Exterior” in “Warm Acrid Herbs”, the acrid, sweet and warm Cinnamomum twig (gui zhi) enters the Heart, Lung and Bladder channels. It induces perspiration and dispels pathogenic factors from the muscles, restores menstruation by warming the vessels, reinforces Yang, unblocks the Yang Qi of the chest, clears Wind-Cold-Damp painful obstruction, warms the middle and descends Qi.
Cinnamomum twig treats cold due to Wind-Cold, epigastric pain with cold sensations, amenorrhea, arthralgia, edema due to retention of phlegm and fluids, palpitations, gastro-intestinal upset with a feeling of gas ascending in the abdomen.
It has been shown to have the following indications: antipyretic, diaphoretic, vasodilator, anti-spasmodic, analgesic, cholagogue, antibacterial, hypoglycaemic and diuretic.
Botanical outline
Cinnamomum cassia is a member of the Lauraceae (laurel) family, The family contains over 3000 species from 50 genera. They are mostly aromatic, flowering, evergreen trees or shrubs occurring in warm temperate and tropical regions. The genus Cinnamomum has 250 species distributed through South East Asia, China and Australia. India has 26 species including ‘true’ cinnamon (cinnamomum verum) a native of South India and Sri Lanka.
Cinnamomum cassia originated in southern China and now widely cultivated in southern Asia. It is one of several Cinnamomum species whose aromatic bark is used as a spice and medicinally including Ceylon cinnamon (C. verum also called C. zeylanicum) from Sri Lanka, Saigon or Vietnamese cinnamon (C. loureiroi,) and Indonesian cinnamon (C. Burmanii). Cassia has a warmer and more spicy flavour than Ceylon cinnamon, is generally a medium to light reddish brown, hard and woody in texture, and thicker (2–3 mm (0.079–0.118 in) thick), as all of the layers of bark are used. Ceylon cinnamon, using only the thin inner bark, has a lighter brown colour, a finer, less dense and more crumbly texture. They can be distinguished on the basis of their different chemical composition: Ceylon cinnamon contains eugenol and benzyl benzoate in comparison to Cassia cinnamon but no (at most traces of) coumarin and delta-cadinene (Jayatilaka et al. 1995.
Cinnamomum cassia grows to 10–15 m tall, with greyish bark and alternate, leathery, elongated leaves that are 10–15 cm long and reddish when young. The midribs and lateral veins are conspicuously excavated. Small, white flowers form axillary panicles and the fruit are black-purple and ellipsoidal.The bark is stripped in the autumn and dried in the shade. It is sold as sticks for medicinal use and ground to a powder for use as a culinary spice. It is produced primarily in the southern Chinese provinces of Guangxi, Guangdong, Fujian and Yunnan.