Micronutrient testing is often available for colds. Micronutrient testing is done by taking a blood specimen so that the levels of iodine, zinc, iron, copper, molybdenum, chromium, and selenium in the body can be measured. Colds do not usually affect the final results of a trace element test, so it is possible to have a trace element test during a cold. At present, there is no uniform and accurate international standard for trace element test, and the standard reference value of trace element test may vary in different hospitals, different instruments and different reagents, etc. The results of trace element test have limited value in clinical work. Healthy people with a normal diet are rarely deficient in trace elements, so it is advisable to follow the advice of a medical professional as to whether or not this test is necessary, and should not abuse this test blindly.