Sudden trembling of the baby when eating milk may be caused by physiological or pathological factors, physiological factors such as imperfect development of the nervous system; pathological factors such as calcium deficiency, etc., can cause sudden trembling of the baby when eating milk. 1. Physiological factors: the baby’s nervous system is not well developed, can not fully control their own muscle response, so in the milk and other relaxation state, there can be a sudden trembling of the body. 2. Pathological factors: calcium deficiency in babies can lead to increased excitability of the nervous system, causing uncontrolled neuromuscular reactions in babies, such as sudden trembling during breastfeeding. In addition, calcium-deficient babies can also have symptoms such as irritability, easy sweating and growth retardation. When you find that your baby suddenly trembles when breastfeeding, there may be other reasons, it is recommended that you go to the hospital in time to improve the examination to clarify the cause of the disease, and then give targeted treatment or treatment under the guidance of the doctor.