In addition to the most common nutritional anemia, there are other manifestations of iron deficiency in infants and young children that are easily overlooked and misdiagnosed, specifically the following: 1. Iron deficiency anemia is the most common, mainly manifested as pallor or pale yellow, easy fatigue, loss of appetite, lack of concentration, memory loss, etc., and because of the decline in cellular immune function, often prone to repeated respiratory infections, seriously endangering the physical and mental health of the child. 2. Infant breath-holding The symptoms are mostly seen in children aged 1-3 years old who cry and scream after being aggrieved or stimulated, with apnea or even cyanosis, and stop holding their breath and crying after about 10 seconds to a few minutes. 3. xenophagia, disinterest in normal diet, and studies have found that children with xenophagia have significant iron and zinc deficiency, which improves after supplementation. 4. crossed leg rubbing syndrome, often found in girls with both lower extremities crossed, straightened, and forcefully In addition, there may be neurological deafness, atrophic rhinitis and other manifestations.