Lung meridian is the abbreviation of Hand Sun Lung meridian, which is one of the twelve meridians of the human body, and its detoxification time is usually between 3 and 5 am. According to Chinese medicine, the main function of the lung is “the lung is the master of qi, the division of respiration”, which means that the body inhales clear qi from nature through the lung and then exhales turbid qi from the body to ensure the normal metabolism of the body. The lung meridian is most active between 3 and 5 a.m., when it begins to run, distribute qi and blood, and continuously eliminate toxins from the lungs, including carbon dioxide and oxygen metabolism products and waste. This period is also the time when lung tissues repair themselves during the body’s sleep, and if good, adequate sleep is ensured during this time, it is beneficial for lung maintenance. Patients with poor lung health are advised to quit smoking on a daily basis, avoid dusty areas, and do personal protection for those working in textile and asbestos tile factories. In addition, it is best not to overindulge in spicy foods to avoid hurting the lungs, and to try to exercise moderately to ensure adequate lung capacity.