The best time to drink light salt water is in the morning on an empty stomach, 30-50ml is appropriate. Drinking light salt water in the morning after waking up helps the body to quickly recover the water lost during sleep, helps to wake up the body’s metabolic system, promotes the body’s blood circulation, accelerates the gastrointestinal tract peristalsis, discharges the metabolic waste and the body during sleep, which is beneficial to the body’s laxative and skin whitening. And salt has an antiseptic effect, can prevent the growth of oral bacteria, to avoid oral diseases. However, it is not recommended to drink light salt water at night before going to bed, as it may cause sodium retention, leading to paroxysmal hypertension at night and causing further water and sodium retention in the body. In addition, since people already consume enough sodium in their diet under modern daily eating habits, additional consumption of light saline may lead to the intake of more sodium than required by the body and affect their health, so care needs to be taken.