One year old babies have been crying more than may be hungry, gastrointestinal dysfunction, vitamin D deficiency and other causes. 1. Hunger: usually more than a year old baby is in the growth and development period, its dietary needs will also grow rapidly, if not satisfied, may have been crying. 2. Gastrointestinal dysfunction: the general gastrointestinal digestive function of one-year-old babies is weak, if the child eats too much, there may be abdominal distension, diarrhea, abdominal pain and other symptoms, resulting in more than just crying all the time. 3. lack of vitamin D: if the baby lacks vitamin D, may lead to the occurrence of low blood calcium and low blood phosphorus, which leads to the child to appear easy to frighten, sleep disturbances, crying and so on. One year old baby has been crying more than, there may be other reasons, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.