In Traditional Chinese Medicine (TCM), Yu Gan Zi belongs to the 'Herbs that cool the Blood' category. Herbs in this category are used to clear inflammatory and infectious conditions, referred to as 'Internal Heat' in TCM. This is why most of the herbs in this category will have both antibacterial and antiviral properties. In TCM one has too much 'Internal Heat' in their body as a result of a deficiency of 'Yin' (which is Cold in nature, see our explanation on Yin and Yang) or, more commonly, an Excess of Yang (Hot in nature). Herbs that cool the Blood treat the latter and as such tend to be Cold or Neutral in nature.

As suggested by its category Yu Gan Zi is Cool in nature. This means that Yu Gan Zi tends to help people who have too much 'Heat' in their body, although with less effect than a plant that would be Cold in nature. Balance between Yin and Yang is a key health concept in TCM. Those who have too much Heat in their body are said to either have a Yang Excess (because Yang is Hot in nature) or a Yin deficiency (Yin is Cold in Nature). Depending on your condition Yu Gan Zi can help restore a harmonious balance between Yin and Yang.

Yu Gan Zi also tastes Bitter and Sour. The so-called 'Five Phases' theory in Chinese Medicine states that the taste of TCM ingredients is a key determinant of their action in the body. Bitter ingredients like Yu Gan Zi tends to have a cleansing action on the body by clearing Heat, drying Dampness and promoting elimination via urination or bowel movements. On the other hand Sour ingredients help with digestion and restrain abnormal discharges of Fluids from the body, such as diarrhea or heavy sweating.

The tastes of ingredients in TCM also determine what Organs and Meridians they target. As such Yu Gan Zi is thought to target the Stomach and the Lung. In TCM the Stomach is responsible for receiving and ripening ingested food and fluids. It is also tasked with descending the digested elements downwards to the Small Intestine. In addition to performing respiration, the Lungs are thought in TCM to be a key part of the production chain for Qi and the Body Fluids that nourish the body.