Vitamin C deficiency starts slowly and may present with agitation, bleeding, and iron deficiency anemia. Dietary vitamin C deficiency takes about 3 to 4 months to develop into vitamin C deficiency. Early manifestations include agitation, irritability, lethargy, loss of appetite, weight loss, and pallor, which may be accompanied by low-grade fever, vomiting, diarrhea, and susceptibility to infection or wound healing. With the development of the disease, it is common to see bleeding under the periosteum of the long bones, skin and mucous membranes. Repeated gum bleeding, nosebleeds, occasional gastrointestinal bleeding, hematuria, bleeding in joint cavities and even intracranial bleeding may occur. One of the early symptoms in infants is pain in the limbs in a froggy position, and any movement of their limbs causes them to be so painful that they cry. Iron deficiency anemia is caused by prolonged bleeding and vitamin C deficiency, which affects iron absorption and utilization.