Constitutions are classified according to the Yin–Yang theory, the five elements theory, Qi, blood, body fluid, and viscera. The more common classifications follow:
(1)Abundance of Yang brings heat. Yang symbolizes heat, as is reflected in the heat characteristics of its constitution. These include a reddish complexion, a resounding voice, warm hands and feet, dry feces, slightly yellow urine, cold tolerance, heat intolerance, and a slightly rapid pulse. Other, less visible symptoms of heat include heart-fire flare-ups, Liver-Yang hyperactivity, etc.
(2)Deficiency of Yang brings cold. Yang symbolizes heat, so its deficiency engenders cold characteristics. These include a pale complexion, cold feet and hands, spontaneous sweating, impotence, diarrhea, excessive clear urine, and a deep–slow pulse. Less visible symptoms of yang deficiency include insufficiency of heart-Yang, spleen-Yang, Kidney-Yang, etc.
(3)Abundance of Yin brings cold. Yin symbolizes cold, so its constitution contains cold characteristics. These include a bluish complexion, a quiet voice, cold hands and feet, soft feces, clear urine, heat tolerance, cold intolerance, and a slightly slow pulse. Less visible symptoms of cold include stagnation of cold in the Liver meridian, cold in the Lungs, Spleen, and Stomach, etc.
(4)Deficiency of Yin generates heat. Heat symptoms include reddish cheeks, an abnormally lean body, feverish palms and feet, insomnia, night sweats, dry feces, scanty brownish urine, and a thin–rapid pulse. Depending on the location of the heat, the symptoms may include insufficiency of Heart-Yin, Liver-Yin, Lung-Yin, Spleen-Yin, and Kidney-Yin.
(5)Deficiency of Qi weakens functions of the viscera. The Qi deficiency symptoms include a pale complexion, soft voice, tired appearance, poor appetite, weak pulse, etc. Depending on the viscera, the symptoms include insufficiency of Heart-Qi, Lung-Qi, Spleen-Qi, and Kidney-Qi.
(6)Deficiency of blood malnourishes the viscera. The Blood deficiency symptoms include pale complexion, lips and nails, insomnia, dreaminess, weakness and numbness in the limbs, a light-colored tongue, a thin–weak pulse, etc. Depending on the viscera, the symptoms include insufficiency of Heart-blood, Liver-blood, etc.
(7)Excess damp is the metabolic disturbance of body fluid, which may arise from a prolonged stay in humid areas. Common symptoms include obesity, dizziness, excess phlegm, nausea, poor appetite, mucous feces, a thick greasy-tongue coating, and a slippery-pulse. Depending on the viscera affected, dampness may accumulate phlegm in the Lungs, the spleen, etc.
(8)Blood stasis is the internal retention of blood in various body parts caused by poor blood circulation. The symptoms include a grayish complexion, a sluggish body, a purplish tongue, head and limb pain, a thin and irregular pulse, irregular menstruation in women, etc. Depending on the viscera, blood stasis can block the heart meridian, the Liver meridian, etc.