Feeling itchy all over the body is caused by a variety of reasons, mainly including environmental factors, dietary factors, disease factors, as follows: a. Environmental factors: the surrounding environment stimulation, such as frequent contact with dust, dust, dust mites, animal dander or plant pollen, easily cause skin allergies, causing itching all over the body. In addition, minor friction, pressure, temperature, humidity changes, can also cause the whole body itchy skin, such as cold winter humidity is low, sebum secretion is reduced, dry and itchy skin. Second, dietary factors: eating certain easily allergenic food, such as fish and shrimp, seafood, mangoes, etc., resulting in skin metamorphosis, itching symptoms. Third, disease factors: 1, the skin itself diseases: mainly dermatitis, eczema, urticaria, etc., most of these diseases are accompanied by itching symptoms, and generally caused by internal and external factors; 2, systemic diseases: mainly chronic kidney disease, diabetes, chronic kidney disease because of abnormal kidney function, resulting in the body’s toxins can not be effectively excreted out of the body, deposited in the blood, subcutaneous or skin tissue, stimulating peripheral nerves and cause itching. Diabetic patients mainly because the glucose content of the skin is higher than normal, which will stimulate the nerve endings in the skin and cause disruption of sensory function thus causing itchy skin.