Thick white tongue coating at the root may be caused by kidney yang deficiency, unfavorable qiization, phlegm-dampness stagnation in the lower jiao, etc., but the specific cause should be decided in conjunction with the patient’s other symptoms. In patients with kidney yang deficiency and unfavorable qi transformation, in addition to the symptoms of thick white tongue coating, they may also be accompanied by coldness (cold body), cold limbs, lack of mental energy, shortness of breath and wheezing, lumbar and knee soreness (feeling of soreness and weakness in the lumbar region and knees), impotence, spermatorrhea or oedema, and urinary incontinence. Patients with phlegm-dampness stagnating in the lower jiao may not only have the symptoms of thick white tongue coating, but also may be accompanied by heavy limbs (weakness and heaviness of the limbs), chest and epigastric constriction, low food intake and greasy mouth, loose stools, and oedema of the lower limbs. If there are other discomforts associated with thick white tongue coating, it is recommended to consult a doctor in time.