Understanding the San Jiao (Triple Burner) in Traditional Chinese Medicine

 Kit Li

What is the SanJiao (1, 2) in Traditional Chinese Medicine (TCM)? What are its functions, and where is it located in the body? These are some of the most intriguing questions in TCM.

In TCM, the San Jiao (三焦) is described as having “a name but no physical form” (有名无形). In anatomical terms, it is considered invisible, you cannot dissect the body and identify a specific structure called the San Jiao. However, it is regarded as a key regulator of internal balance, and maintaining its smooth function is important for supporting overall health.

The San Jiao is divided into three parts within the body: the Upper Jiao, Middle Jiao, and Lower Jiao. Together, they are responsible for regulating the movement of Qi, body fluids, and nutrients derived from food and drink.

1) Upper Jiao (Shang Jiao)

The Upper Jiao is located in the chest area and includes the Heart and Lungs. Its main function is distribution, spreading Qi, circulating fluids to the skin, and regulating the opening and closing of the pores, as well as supporting immunity (Wei Qi).

From a modern physiological perspective, the Upper Jiao can be loosely related to functions such as breathing, oxygen exchange, circulation to the body’s surface, immune surveillance, and the vapour-like exchange of fluids through the lungs and skin. When it is dysfunctional, symptoms may include chest tightness, shallow breathing, frequent colds, and dryness of the skin.

2) Middle Jiao (Zhong Jiao)

The Middle Jiao is located between the diaphragm and the navel and includes the Spleen and Stomach. It is responsible for digestion and absorption, transforming food into Qi and Blood, and managing the transportation of nutrients throughout the body.

It may be loosely associated with processes such as enzymatic digestion, gut microbiome activity, nutrient absorption, and the metabolic conversion of food into usable energy. When the Middle Jiao becomes sluggish, symptoms may include bloating, brain fog, low energy after meals, and a general sensation of dampness or heaviness in the body.

3) Lower Jiao (Xia Jiao)

The Lower Jiao is located below the navel and includes the Kidneys, Bladder, and Large and Small Intestines, essentially the organs in the lower abdomen. It manages waste elimination and fluid metabolism, functioning much like the body’s internal drainage system.

From a modern physiological perspective, the Lower Jiao may be loosely associated with kidney filtration, water reabsorption in the colon, hormonal regulation of fluid balance, and pelvic circulation. When this system becomes obstructed or inefficient, it may lead to issues such as edema (water retention), constipation, difficulty with urination, PMS, or a feeling of pelvic heaviness.

In TCM theory, if any of the San Jiao is not functioning smoothly, the body may become more prone to illness because Qi and fluids are not being transported efficiently due to blockages along the meridians.

To support the SanJiao in daily life, it is important to eat in moderation by avoiding overeating and limiting cold or greasy foods, while choosing easily digestible meals to protect the Middle Jiao. Maintaining emotional balance is also essential, as stress, anxiety, and low mood can disrupt the movement of Qi. Gentle exercise such as walking, light jogging, or practices like Ba Duan Jin can help improve the circulation of Qi and Blood.

In addition, acupressure points such as Shanzhong (RN-17), located at the midpoint between the nipples, may help open the chest and support the Upper Jiao; Zhongwan (RN-12), located 4 cun above the navel, may support digestion; and Guanyuan (RN-4), located 3 cun below the navel, may help tonify the Lower Jiao.

Herbal teas can also be used as supportive measures, such as Peppermint and lemon tea (3) for Upper Jiao support, Hawthorn and dried tangerine peel tea (4) to aid digestion in the Middle Jiao, and Corn Silk Tea to promote urination and reduce water retention in the Lower Jiao.

Ultimately, while the San Jiao may not correspond to a single physical structure in modern anatomy, it offers a valuable functional framework in TCM for understanding how the body regulates the movement, transformation, and elimination of Qi and fluids. By supporting the harmonious interaction between the Upper, Middle, and Lower Jiao through mindful lifestyle habits, gentle exercise, acupressure, and dietary choices, we can help maintain internal balance and promote overall well-being.

References:

1) Sanjiao:  https://www.sciencedirect.com/topics/nursing-and-health-professions/san-jiao

2) Conceptualizing a Traditional Chinese Medicine Organ: The Triple Energizer (San Jiao):https://pmc.ncbi.nlm.nih.gov/articles/PMC9248333

3) Pepperming Tea: https://pubmed.ncbi.nlm.nih.gov/9283698/

4) Hawthron and Chenpi Tea: https://kitli-vitaqiholistic.blogspot.com/2025/12/gentle-digestive-support-with-hawthorn.html

5) Corn Silk Tea: https://pubmed.ncbi.nlm.nih.gov/15957371/