Trace element tests are usually performed by collecting blood or hair and testing the body’s trace element content through instruments, and the accuracy of the results may be inaccurate. Whether the trace element test is necessary or not should be judged according to the age of the person being examined and whether other symptoms are combined. If the baby is under 6 months old, it is not necessary to check the trace elements if there are no uncomfortable symptoms. Because the supply of nutrients for babies under 6 months old mainly comes from breast milk, which can ensure the nutritional needs of babies and usually does not cause micronutrient deficiency in babies’ bodies. Second, trace element examination is necessary for babies under 1, 6 months old: if there are indeed obvious symptoms of discomfort, such as reduced appetite, reduced attention span, stunted growth, decreased intelligence, and suspected deficiencies of trace elements such as zinc, iron, calcium, iodine, etc., trace element examination can be conducted in regular medical institutions on medical advice to check whether there is a deficiency of trace elements; 2, for babies over 6 months old: at this time most babies have If the baby’s complementary food is not added in time or is insufficient, and if the baby is picky or paranoid, there may be a deficiency of trace elements, and it is necessary to check the trace elements of the baby in this period. In addition, the results of the trace element test may have some errors and can only provide some reference, so it is necessary to observe whether your baby has any discomfort. It is necessary for a professional doctor to evaluate the baby’s condition to determine whether it is necessary to have a trace element test.