6 months baby always shaking head may be vitamin D deficiency, eczema, external ear canal tingling and other factors. 1. Vitamin D deficiency: when the 6-month-old baby’s body is excessively deficient in vitamin D, it is easy to make the body lack of calcium, and it will shake its head frequently, which may also be accompanied by sweating, restless sleep, easy to cry, occipital baldness and other symptoms. 2. Eczema: it may be related to dietary and environmental factors, which can lead to eczema at the back of the head, which will cause itching symptoms, and babies will shake their heads to improve the situation, which may be accompanied by redness, crying and so on. 3. Cerumen in the external auditory canal: more cerumen in the baby’s ear, forming cerumen embolism or causing otitis externa, may lead to ear discomfort, and the baby will shake his head frequently. If your 6-month-old baby shakes his head all the time and there are other abnormal manifestations, parents are advised to take their children to the doctor for examination and treatment.