Spring diet should be based on the principle of gentle nourishment, focusing on nourishing the liver and spleen. During this season, the liver is in charge. The physiological characteristics of the liver are like the sprouting of trees in spring, governing the rise of Yang energy throughout the body. If the liver's function is impaired, it leads to the disorder of Qi and blood circulation, disturbing other organs and causing diseases. Furthermore, the sour flavor enters the liver, which is its natural taste. If an already overactive liver in spring consumes an excessive amount of sour food, it will cause an excess of liver Qi. Since the liver over-controls the spleen, this will inevitably damage the spleen. The spleen is also closely related to the stomach, so a weak spleen will hinder the digestive and absorptive functions of the stomach and spleen. The sweet flavor enters the spleen and is best for tonifying the spleen Qi. A healthy spleen, in turn, assists the liver Qi. Therefore, as the centenarian Tang dynasty physician Sun Simiao said, "reduce sour and increase sweet to nourish the spleen Qi." This means eating less sour and more sweet foods to nourish both the liver and spleen, which is greatly beneficial for preventing illness and maintaining health.
Foods that are warm in nature and sweet in taste are the first choice. These include grains like sticky rice, black rice, sorghum, broomcorn millet, and oats; vegetables and fruits like sword bean, pumpkin, lentil, red dates, longan, walnut, and chestnut; and meat and fish like beef, pork tripe, crucian carp, crucian, sea bass, grass carp, and rice eel. By drawing rich nutrients from these foods, the effects of nourishing the liver and strengthening the spleen can complement each other.
Secondly, one should follow the rising energy of spring and eat more foods that tonify Yang energy. Especially in early spring when there is still the lingering cold of winter, one can choose to eat chives, garlic, onion, konjac, turnip, mustard, coriander, ginger, and scallion. These vegetables are all warm and pungent in nature, which can help disperse wind and cold, and also inhibit and kill bacteria that breed in humid environments.
Again, on warm spring days or during the sudden heat of late spring, it can easily stir up stagnant heat in the body, leading to liver fire, or cause the body's fluids to be lost. It is advisable to eat some foods that clear internal heat and nourish the liver, such as buckwheat, Job's tears, shepherd's purse, spinach, water spinach, celery, chrysanthemum seedlings, lettuce, eggplant, water chestnut, cucumber, and mushroom. These foods are cool and sweet in nature, which can clear internal heat, moisten the liver, and brighten the eyes.
As for fresh fruits, although they have the effects of clearing heat, generating fluids, and quenching thirst, most are sour and not suitable for excessive consumption in spring. If you need to clear internal heat, it is better to eat sweet and cool fruits like bananas, raw pears, sugarcane, or dried fruits like persimmon cake.