If the nipple is squeezed out white if there is no swelling and pain, it is considered to be normal, but it may also be caused by inflammation of the mammary gland, papilloma and other reasons. 1. Normal: After the end of breastfeeding, there will be residual milk in the milk ducts, most of which will be slowly absorbed after the end of breastfeeding, and a very small portion of it will be accumulated in the milk ducts, so there will be a small amount of white milk secreted by squeezing the nipple, which is a normal phenomenon. 2. Breast inflammation: Breast inflammation and part of breast hyperplasia will show abnormal breast secretion, which can be detected and diagnosed through retrograde imaging of the nipple or through lactoscopy. 3. Papilloma: patients will show yellowish secretion, when the overflow is partially absorbed, squeeze the nipple, white paste-like material can be seen. When patients have white discharge from the nipple, after excluding physiological factors, they should go to the hospital in time to clarify the cause of the disease and receive reasonable treatment under the guidance of the doctor.