The Sanfu Days (the hottest period of the year in the Chinese calendar) are when yang energy reaches its peak. During this time, the three external factors of heat, humidity, and dampness dominate and most easily attack the spleen and stomach.
In this season, the humidity in the air is high. People often stay in air-conditioned environments and consume cold foods and drinks, such as chilled fruits and icy beverages. These habits can weaken the spleen and stomach, leading to symptoms like poor appetite, bloating, constipation or diarrhea, fatigue, and lack of energy. Besides weather-related factors, the decline in digestive function also plays a role. The combination of dampness and internal cold causes double the damage to the spleen’s yang energy, significantly compromising digestive health.
In Traditional Chinese Medicine (TCM), both the long summer season and the spleen are associated with the Earth element. Their close correlation makes this period an excellent opportunity to treat spleen and stomach issues such as: indigestion, stomach pain, diarrhea, chronic gastritis, enteritis, and other digestive system disorders.
Among children, the most common issue is spleen deficiency, which can lead to food retention, internal heat, constipation, poor sleep, and a weakened immune system. Spleen deficiency is a root cause of repeated illnesses and even allergic conditions in children.
On Sanfu Days, herbal plasters are applied to acupuncture points on the abdomen and lower limbs—such as Zhongwan, Xiawan, Qihai, Guanyuan, and Zusanli —as part of a therapy known as Sanfu Moxibustion. This method warms the meridians, disperses cold, and harmonizes the spleen and stomach. It is especially beneficial for treating cold-induced gastrointestinal symptoms caused by frequent consumption of cold foods.
Therefore, undergoing Sanfu Moxibustion during this season embodies the principle of “treating winter diseases in summer.” It helps clear heat and dampness, expel internal cold, unblock the body’s meridians, strengthen constitution, and boost immunity—offering substantial complementary benefits for many chronic conditions.
Dr. Bi Lihong
Registered Traditional Chinese Medicine Practitioner
Chinese Medicine Council of Hong Kong
