Eucommia bark

Chinese: 杜仲

Pinyin: Dù Zhòng

Parts used: Dried stem bark

TCM category: Tonic herbs for Yang Deficiency

TCM nature: Warm

TCM taste(s): Sweet

Meridian affinity: KidneyLiver

Scientific name: Eucommia ulmoides

Other names: Rubber tree bark

Use of eucommia bark (Du Zhong) in TCM

Please note that you should never self-prescribe TCM ingredients. A TCM ingredient is almost never eaten on its own but as part of a formula containing several ingredients that act together. Please consult a professional TCM practitioner, they will be best able to guide you.

Preparation: Remove the bark from the tree and let it dry under the sun

Dosage: 6 - 12 grams

Main actions according to TCM*: Tonifies the Liver and Kidneys. Calms ascendant Liver Yang (hypertension/high blood pressure). Calms a restless fetus.

Primary conditions or symptoms for which eucommia bark may be prescribed by TCM doctors*: Lumbago Miscarriage Hypertension Fatigue Dizziness Headache

Contraindications*: This herb should not be used by those with Heat signs associated with Yin Deficiency; it should not be used in conjunction with Ningpo figwort root (Xuan Shen).

Key TCM concepts behind eucommia bark (Du Zhong)'s properties

In Traditional Chinese Medicine (TCM), eucommia bark are plants that belong to the 'Tonic herbs for Yang Deficiency' category. Tonic herbs are used for patterns of Deficiency, when one lacks one of the 'Four Treasures' (Qi, Blood, Yin and Yang). Yang Tonics are generally used in combination with a small amount of Yin tonics. If Yin is deficient, neither Qi nor Yang herbs alone will be effective. The most common symptoms associated with Yang Deficiency are low libido and impotence. It is worth mentioning that another very effective remedy against Yang Deficiency is regular exercise.

Furthermore eucommia bark are plants that are Warm in nature. This means that eucommia bark tend to help people who have too much "cold" in their body, although with less effect than a plant that would be Hot in nature. Balance between Yin and Yang is a key health concept in TCM. Those who have too much cold in their body are said to either have a Yin excess (because Yin is Cold in nature) or a Yang deficiency (Yang is Hot in Nature). Depending on your condition eucommia bark can help restore a harmonious balance between Yin and Yang.

Eucommia bark also taste Sweet. The so-called "five elements" theory in Chinese Medicine states that the taste of TCM ingredients is a key determinant of their action in the body. Sweet ingredients like eucommia bark tend to slow down acute reactions and detoxify the body. They also have a tonic effect because they replenish Qi and Blood.

The tastes of ingredients in TCM also determine what organs and meridians they target. As such eucommia bark are thought to target the Kidney and the Liver. According to TCM, the Kidneys do not only regulate the urinary system but also play a key role in the reproductive system and the growth and aging process of the body. The Liver on the other hand is often referred as the body's "general" because it is in charge of regulating the movements of Qi and body fluids. It also takes a leading role in balancing our emotions.

Research on eucommia bark(Du Zhong)

Standardized Eucommia extract reduces blood pressure and has beta-adrenergic blocking activity.1

The extracts of Eucommia showed anti-hypertensive, anti-complementary, anti-oxidative, and anti-gastric ulcer effects, and promoting collagen synthesis, accelating granuloma formation, and other pharmacological effects.2

Bushen Qiangdu Recipe (consisting of eucommia bark) showed significant effect in treatment of ankylosing spondylitis.3

Sources:

1. Greenway F, Liu Z, Yu Y, Gupta A. (2011). A clinical trial testing the safety and efficacy of a standardized Eucommia ulmoides Oliver bark extract to treat hypertension. Altern Med Rev. , 16(4):338-47.

2. Deyama T, Nishibe S, Nakazawa Y. (2001). Constituents and pharmacological effects of Eucommia and Siberian ginseng. Acta Pharmacol Sin. , 22(12):1057-70.

3. Wang H, Yan XP, Kong WP. (2011). Effect of bushen qiangdu recipe on osteoporosis and bone loss of patients with ankylosing spondylitis. Zhongguo Zhong Xi Yi Jie He Za Zhi. , 31(4):471-5.