Urinary organs are involved in producing urine and discharging it from the body. In the course of metabolism waste and other toxic substances are produced inside the body, and soluble salts and nitrogenous compounds are expelled from the body in the form of urine.
   Therefore, strengthening the urinary organs is important to improve the functions of all the internal organs, promote the health and retard aging.
   Those with poor urinary organs have a feeling of thirst, difficulty in getting to sleep, cold sweat, dizziness, tooth disorders, excessive dreaming, waist pains, weak legs, and chilly hands and feet, are susceptible to cold and have weak sexual activity. For such reasons they suffer nocturia, dysfunctional uterine bleeding, infertility, pulmonary tuberculosis, diabetes, chronic hepatitis, arteriosclerosis, impotence, amenorrhea, miscarriage, gestational edema, hypopituitarism, hypothyroidism, chronic nephritis, hypertension, cardiovascular diseases and nerve deafness.
   Prickly water lily, Radix Rehmaniae, plantain, Tuckahoe, Eucommia ulmoides Oliv, cornsilk and chaff flower root are widely used as Koryo medicinal ingredients, and snakehead, cucumber, potato, trepang, guts of pig, kidney of sheep, dog meat, goldfish, mud snail, carp, eggplant, parsley, lettuce, water melon, chicken, wax gourd, bamboo sprout and pumpkin as food materials.
   Since the urinary organs consume a lot of energy in supplying all the materials needed in the body as well as storing some substances, they are scarcely in good condition. So in Koryo medicine it is highly recommended to strengthen these organs by eating dishes prepared with tonics.