Why does “spring wind” (Wind pathogen) lead to summer diarrhea?

Why does “spring wind” (Wind pathogen) lead to summer diarrhea?

Spring – when Wind arises, illness also arises
The ancients said: “Wind is the leader of a hundred diseases.”
Spring is the time when yang-qi is newly generated; the body is still weak, the pores are open, and the qi and blood begin to circulate again after a long, quiescent winter.
At this moment, external Wind easily takes advantage and invades through the skin—especially when one goes into the wind early in the morning, bathes while the body is still warm, or removes clothing too soon.

At first, Wind remains on the exterior, causing headache, aversion to wind, and stiffness of the nape. But if not expelled completely, Wind hides within and follows the channels inward—especially entering the Liver channel, because the Liver corresponds to spring, to Wind, and to Wood.

Wind invading the Liver – Wood movement becomes disrupted
According to the Five Elements, spring belongs to Wood, and the Liver is the Wood organ, governing the function of dispersing and regulating the flow of qi and blood.
Normally, the Liver’s qi moves like a gentle spring current flowing through fields, nourishing all things.
When Wind pathogen invades, two forms of “movement” clash: the Liver is inherently active, and Wind is also active. Their interaction disturbs the balance of qi, causing disordered movement and impaired dispersing.

When the Liver cannot disperse freely and becomes constrained, it leads to “Liver qi transversely counterflowing.”
Liver-Wood is like a branch being bent repeatedly—pressure builds internally, and when released, it rebounds forcefully. Thus, when this constraint erupts, it becomes excessive and rebellious, manifesting as chest oppression, hypochondriac distension, poor digestion, irritability, and restlessness—classic signs of Liver constraint.

Entering summer – exuberant Wood restrains Earth, generating Dampness and diarrhea
Entering summer, the natural qi changes: yang reaches its peak, humidity increases, rains are frequent, and damp vapors rise from the ground.
The already-constrained Liver-Wood, when stimulated by summer heat, flares even further.
According to the Five Elements, when Wood is excessive, it restrains Earth.
The Spleen belongs to Earth and governs the transformation of food and fluids.

When the Spleen is restrained → its transforming function weakens → Dampness arises.
Dampness accumulating in the middle burner causes abdominal fullness, loose stools, heaviness of the body, and fatigue.

This is the phenomenon known as “spring Wind entering the Liver, summer Dampness attacking the Spleen”—a continuous causal chain linking the two seasons.
Imagine the Liver as plants overgrowing in a garden; when branches grow too vigorously, they deplete the soil, leaving it weak, moist, and waterlogged. This reflects the sequence: Liver constraint → Wood excess → Earth deficiency → Dampness formation → diarrhea.

Wind is the trigger; Dampness is the consequence
• Spring: Wind invades the Liver → Liver qi becomes constrained and rebellious → Wood becomes excessive.
• Summer: Liver-Wood becomes even more excessive under summer heat → the Spleen (Earth) is restrained → impaired transformation of fluids → Dampness forms → diarrhea.

Wind invasion in spring is the seed; Dampness arising in summer is the fruit.
Illness does not appear without cause—it is the result of the body’s qi mechanism falling out of harmony with seasonal influences.

Methods of health preservation and prevention

• In Spring:
Keep the neck and nape warm, avoid cold spring winds, and do not remove clothing too early.
Eat light, increase greens, and reduce spicy or heating foods.
Practice gentle exercises such as qigong, tai chi, or morning walking to help the Liver disperse qi and prevent stagnation.

• In Summer:
Strengthen the Spleen and transform Dampness.
Eat coix seed, red beans, and brown rice. Avoid cold beverages and ice.
Those who suffered Wind invasion in spring should expel the pathogen early, lest Dampness arise in summer and cause diarrhea.

Traditional medicine views humans as part of nature, influenced directly by seasonal qi.
In spring, yang-qi is just beginning to grow and Wind easily invades; in summer, Dampness is abundant and illness readily manifests.
Understanding this allows one to follow seasonal rhythms and harmonize body and mind.
A seemingly harmless spring breeze, if not guarded against, may sow the seed for summer diarrhea.
To follow seasonal principles is to live in harmony with nature.