# Guizhi (Cinnamomum cassia twig)

**Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/guizhi
**Data Source:** Hermetica Superfoods Ingredient Encyclopedia
**Updated:** 2026-03-29
**Evidence Score:** 2 / 10
**Category:** Traditional Chinese Medicine
**Also Known As:** Cinnamomum cassia twig, Cassia twig, Chinese cinnamon twig, Ramulus Cinnamomi, Gui Zhi, Cinnamon branch, Chinese cassia branch, Cassia bark twig

## Overview

Guizhi, the dried twig of Cinnamomum cassia, contains cinnamaldehyde and cinnamic acid as its primary bioactive compounds, which modulate [inflammatory pathway](/ingredients/condition/inflammation)s and peripheral circulation. In Traditional Chinese Medicine, it is classified as acrid and warm, used to release the exterior and warm the channels by harmonizing Ying and Wei Qi.

## Health Benefits

• Supports respiratory health and relieves cold symptoms, as traditionally used in TCM, though no human clinical evidence supports this.
• Believed to help balance Ying and Wei Qi to combat wind-cold invasions, based on traditional usage.
• May have [anti-inflammatory](/ingredients/condition/inflammation) properties due to volatile compounds like cinnamaldehyde, but lacks human study confirmation.
• Could enhance circulation and relieve muscle pain, as per historical applications, without clinical backing.
• Potentially aids in menstrual irregularities through its warming effect, according to TCM practices.

## Mechanism of Action

Cinnamaldehyde, the principal volatile constituent of Guizhi, inhibits NF-κB signaling and suppresses COX-2 enzyme activity, reducing [pro-inflammatory cytokine](/ingredients/condition/inflammation) production including TNF-α and IL-6. Cinnamic acid and its derivatives act as transient receptor potential (TRP) channel modulators, particularly TRPA1, which may explain the warming and vasodilatory sensations associated with its use. Additionally, procyanidins present in the twig fraction have demonstrated inhibition of thromboxane A2 synthesis, potentially contributing to its traditional use in promoting blood circulation.

## Clinical Summary

Human clinical evidence specifically for Guizhi twigs is sparse; most available data derives from in vitro studies and animal models examining cinnamaldehyde and related phenolic compounds. A small number of studies on Guizhi Tang (a classical TCM formula containing Guizhi) in populations with common cold or influenza symptoms suggest modest symptomatic relief, though these trials typically involve fewer than 100 participants and lack rigorous blinding. Preclinical rodent studies demonstrate [anti-inflammatory](/ingredients/condition/inflammation) and antipyretic effects at doses of 50–200 mg/kg of Guizhi extract, but direct human dose-equivalent translation remains unestablished. Overall, the evidence base is preliminary and insufficient to support definitive clinical claims without larger, controlled human trials.

## Nutritional Profile

Guizhi (Cinnamomum cassia twig) is used in small medicinal doses (3–9g dried twig per decoction) rather than as a food, so macronutrient contribution is negligible. Key bioactive compounds include: Volatile oils (1–2% of dry weight), dominated by trans-cinnamaldehyde (60–75% of the essential oil fraction), which is the primary pharmacologically active constituent. Other volatile components include cinnamyl acetate (~3–5%), eugenol (~1–2%), β-caryophyllene (~2–4%), and linalool (trace amounts). Phenolic compounds are present, including cinnamic acid derivatives and coumarin (approximately 0.45–0.95mg/g dry weight — notably higher in cassia-derived material than Ceylon cinnamon, warranting caution with high-dose long-term use due to hepatotoxic potential of coumarin). Procyanidin-type polyphenols and flavonoids are present in modest amounts, contributing to [antioxidant activity](/ingredients/condition/antioxidant) (ORAC values broadly comparable to other cinnamon materials, estimated 1,000–3,000 µmol TE/100g dry weight for bark/twig material). Diterpenes including cinnzeylanol and cinnzeylanine have been identified in small quantities. Mineral content includes trace manganese, calcium, and iron, though amounts delivered per standard decoction dose are pharmacologically insignificant. Carbohydrates (primarily cellulose, hemicellulose, and starch) constitute the bulk dry mass (~60–70%) but are largely insoluble and not bioavailable via decoction. Bioavailability note: Aqueous decoction extracts cinnamaldehyde and water-soluble polyphenols efficiently; cinnamaldehyde is rapidly absorbed but also rapidly metabolized to cinnamic acid in vivo, with peak plasma levels within 30–60 minutes. Coumarin is water-soluble and readily extracted into decoctions, making intake monitoring relevant for chronic use.

## Dosage & Preparation

There are no clinically studied dosage ranges for Guizhi due to the absence of human trials. Commercial products contain dried twig powder and liquid extracts, but lack standardization details. Essential oils are for topical use only. Consult a healthcare provider before starting any new supplement.

## Safety & Drug Interactions

Guizhi is generally considered safe at culinary and low supplemental doses, but high doses of cinnamaldehyde may cause gastrointestinal irritation, mouth sores, or allergic contact dermatitis in sensitive individuals. It should be used with caution alongside anticoagulant medications such as warfarin, as its thromboxane-inhibiting properties may potentiate bleeding risk. Guizhi is contraindicated in TCM practice for individuals with heat-excess patterns, presenting with fever from wind-heat invasion, or spontaneous sweating without cold exposure, and is traditionally avoided during pregnancy due to its warming, blood-moving properties. Patients on antidiabetic drugs should also exercise caution, as cinnamon-related compounds can have mild hypoglycemic effects that may alter [blood glucose](/ingredients/condition/weight-management) management.

## Scientific Research

No specific human clinical trials, RCTs, or meta-analyses for Guizhi alone were found. A patent describes animal model studies with cassia twig compositions, but there is no human data or PMIDs available.

## Historical & Cultural Context

In Traditional Chinese Medicine, Guizhi has been used for over 2,000 years to treat colds, fever, and chills by warming and releasing the exterior. It is believed to enter the Heart, Lung, and Bladder channels, addressing symptoms like cough and menstrual irregularities.

## Synergistic Combinations

Poria cocos, ginger, licorice root, peony root, angelica sinensis

## Frequently Asked Questions

### What is Guizhi used for in Traditional Chinese Medicine?

In TCM, Guizhi is classified as acrid, sweet, and warm, and is used to release the exterior by harmonizing Ying (nutritive) and Wei (defensive) Qi, making it a primary herb for wind-cold invasions presenting with fever, chills, and spontaneous sweating. It is also used to warm and unblock the channels, addressing conditions such as cold-type joint pain and menstrual irregularities associated with cold stagnation. Classic formulas like Guizhi Tang (Cinnamon Twig Decoction) have employed it for over 2,000 years.

### What is the difference between Guizhi and Rougui?

Guizhi refers specifically to the young twigs of Cinnamomum cassia, while Rougui refers to the bark of the same plant; both contain cinnamaldehyde but differ in concentration and TCM functional emphasis. Guizhi is considered more dispersing and surface-releasing, directing its action outward to the exterior and limbs, whereas Rougui is warmer and more tonifying, directing its action inward to the Kidney Yang and Ming Men fire. This distinction means they are used for different TCM pattern diagnoses despite sharing the same botanical source.

### Does Guizhi have anti-inflammatory properties?

Preclinical evidence indicates that cinnamaldehyde and cinnamic acid derivatives in Guizhi inhibit NF-κB activation and reduce COX-2-mediated prostaglandin synthesis, producing measurable anti-inflammatory effects in cell and animal models. In rodent studies, Guizhi extract at approximately 100–200 mg/kg bodyweight significantly reduced carrageenan-induced paw edema and lowered serum TNF-α and IL-6 levels. However, these findings have not been replicated in robust human clinical trials, so anti-inflammatory claims in humans remain preliminary.

### Is Guizhi safe to take during pregnancy?

Guizhi is traditionally contraindicated during pregnancy in TCM because of its warm, acrid nature and blood-moving properties, which are believed to risk uterine stimulation. Modern pharmacological data on cinnamaldehyde suggests it may have uterotonic effects at higher concentrations in animal models, supporting this caution. Pregnant individuals should avoid Guizhi supplementation unless under the direct supervision of a qualified TCM practitioner and their obstetric provider.

### What is the typical dosage of Guizhi used in TCM formulas?

In classical and contemporary TCM practice, the standard decoction dose of Guizhi is 3–10 grams of the dried twig per day, typically combined with other herbs in a formula rather than used as a standalone herb. The benchmark formula Guizhi Tang uses 9 grams of Guizhi alongside Baishao, Shengjiang, Dazao, and Zhigancao. Standardized extracts or supplements outside of traditional decoction context do not have well-established human dosing guidelines, and self-prescribing at high doses is not recommended.

### Does Guizhi interact with blood thinners or anticoagulant medications?

Guizhi contains compounds that may have mild anticoagulant properties, and concurrent use with blood thinners like warfarin or aspirin could theoretically increase bleeding risk, though human clinical evidence is limited. Individuals taking anticoagulant medications should consult a healthcare provider before adding Guizhi supplements to their regimen. No serious adverse interactions have been widely documented, but caution is warranted.

### What is the difference between Guizhi twig, Guizhi bark, and whole Cinnamomum cassia cinnamon?

Guizhi specifically refers to the tender twigs of Cinnamomum cassia and is considered gentler and more dispersing than the inner bark (Rougui), which has stronger warming properties. Whole cinnamon sticks or ground cinnamon powder may contain both bark and woody material, making them less refined than pharmaceutical-grade Guizhi twigs used in TCM. The twig form is traditionally preferred for treating exterior conditions like wind-cold, while the bark targets deeper warming.

### What clinical evidence supports Guizhi's effectiveness for cold symptoms in humans?

While Guizhi has been used in TCM formulations for centuries to address cold symptoms, robust human clinical trials demonstrating efficacy are limited and most evidence remains anecdotal or traditional rather than evidence-based. Some preliminary laboratory studies show that cinnamaldehyde and other volatile compounds in Guizhi possess antimicrobial properties, but these have not been validated in controlled human studies. Current research does not provide sufficient evidence to confirm Guizhi's effectiveness for treating common colds in modern medical terms.

---

*Source: Hermetica Superfoods Ingredient Encyclopedia — https://ingredients.hermeticasuperfoods.com*
*License: CC BY-NC-SA 4.0 — Attribution required. Commercial use: admin@hermeticasuperfoods.com*