In Traditional Chinese Medicine (TCM), Cang Zhu belongs to the 'Aromatic herbs that transform Dampness' category. This category of herbs resolves a TCM condition called 'Cold Damp Stagnation', especially as it affects the Stomach and Spleen. In modern medicine this often translates into symptoms such as distended chest and abdomen, lack of appetite, nausea and vomiting
As suggested by its category Cang Zhu is Warm in nature. This means that Cang Zhu tends 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 Cang Zhu can help restore a harmonious balance between Yin and Yang.
Cang Zhu also tastes Bitter and Pungent. 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 Cang Zhu 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 Pungent ingredients tend to promote the circulations of Qi and Body Fluids. That's why for instance someone tends to sweat a lot when they eat spicy/pungent food.
The tastes of ingredients in TCM also determine what Organs and Meridians they target. As such Cang Zhu is thought to target the Spleen and the Stomach. In TCM the Spleen assists with digestion, Blood coagulation and Fluids metabolism in the body. The Stomach on the other hand is responsible for receiving and ripening ingested food and fluids. It is also tasked with descending the digested elements downwards to the Small Intestine.