According to the recommendations of the “Dietary Guidelines for Chinese Residents 2007” issued by the Ministry of Health, ordinary adults should drink at least 1200 ml (6 glasses) of water per day, and drinking plain water is the best choice.

　　 "A day''s plan is in the morning", it is generally believed that the first glass of water in the early morning (from the morning) is particularly important. This is because, during several hours of sleep, without drinking water or eating, but breathing, sweating, and urinary are still in progress, these physiological activities consume and lose a lot of water. The blood is in a relatively viscous state. Replenishing water as soon as possible helps to dilute the blood and prevent the blood from being too viscous. It has a certain effect on preventing thrombosis. It is generally recommended to drink a large glass (250~500 ml) of water immediately after getting up in the morning.

　　 The first glass of water is recommended to drink plain water, not because it is cheap and safe, but because it is the most effective in diluting blood compared to juice, cola, soft drinks, coffee, milk and other beverages. Moreover, boiled water does not contain artificially added sugars, acids, various preservatives, pigments, etc., and it is relatively healthy to drink for a long time. To this end, "Chinese Resident''s Dietary Guide 2007" specifically pointed out that it is a very wrong behavior to replace boiled water with beverages.

　　Many people think that drinking salt water is good for their health, so they drink light salt water in the morning, which is also problematic. Unlike sweating during exercise, the main body loss at night is water, not salt, so there is no need to replenish salt in the morning (salt replenishment is only necessary after a lot of sweating during exercise). Some people will feel more comfortable drinking light saline, and therefore think that light saline is absorbed faster. In fact, there is no evidence that brackish water absorbs faster than ordinary plain water. Moreover, the current salt intake of Chinese people generally exceeds reasonable standards (5, 6 grams per day), and then drink salt water with added salt, which is tantamount to adding frost to the snow.

　　Some people like to drink cold boiled water, but too cold will irritate the stomach and cause gastrointestinal discomfort. Of course, this problem varies from person to person. If drinking cold water does not cause any discomfort, you can drink it. Some people like to drink very hot water, which is also bad and can damage the gastric mucosa. So, even if you do not feel uncomfortable after drinking very hot water, do not get into the habit of drinking hot water. Generally speaking, it is best to drink water in the morning and drink the same boiling water as room temperature. You can drink warm water when it is cold to minimize the stimulation to the gastrointestinal tract. It must be covered when the water is boiled the night before, otherwise it will be easily contaminated by dust and bacteria.

　　 Drinking water early in the morning is best to drink on an empty stomach, that is, drinking water before eating breakfast, and a period of time away from breakfast (such as half an hour). If you drink plenty of water while eating breakfast, it will dilute the gastric juice and affect the digestion and absorption of food. As for whether to drink in a big mouth, or slowly, you can decide according to your gastrointestinal tolerance. The principle is to finish drinking as soon as possible and replenish water in place.