It is not possible to determine Kidney-Yin or Kidney-Yang deficiency based on tongue diagnosis alone, and it is necessary to combine with other symptoms of the patient to decide. However, patients with kidney yin deficiency usually have a red tongue with little moss, while patients with kidney yang deficiency usually have a pale tongue with white moss. 1. Kidney yin deficiency: it can be seen as soreness and pain in the waist and knees, spermatorrhea in men, scanty menstruation or amenorrhea in women, loose teeth and hair loss, dizziness and tinnitus, heart-heat (heat in the hearts of the hands and feet, and self-consciousness of the heart and chest (irritability and sullenness)), hot flashes (the heat feeling starts from the face or the chest, and spreads to the whole body), zygomatic redness (the color of the cheeks and zygomatic bone area is flushed), and red tongue with little moss. 2. Kidney yang deficiency: manifested as dizziness, pale or grayish-black color, lumbar and knee pain, coldness of the whole body (the most obvious in the lower limbs), depression, loss of libido; male impotence and premature ejaculation, infertility of women with uterine cold; prolonged ejaculation of stools, and undigested food in the stools. The tongue is pale, the moss is white, and the pulse is thin and weak. If you have any of the above discomforts, it is recommended to consult a doctor in time.