Drinking salt water before blood donation does not have a very special role.
Drinking a moderate amount of salt water before donating blood can dilute the blood in the body, and it can also replenish the electrolyte ions needed by the body after donating blood, effectively increasing the blood volume of the human body.
A small number of people may experience dizziness, vomiting, panic and other uncomfortable symptoms after donating blood, which can be relieved by drinking a moderate amount of salt water before donating blood.
Blood donation is generally not harmful to health, but it is recommended that people donate blood only twice a year, and each time after a six-month interval before donating a second time.
In addition, it is recommended that people do not do strenuous exercise after donating blood, so as to avoid dizziness, vomiting or even shock and other uncomfortable symptoms, and when uncomfortable symptoms occur, they should go to the hospital in a timely manner.
It should be noted that blood donation needs to go to regular medical institutions, and it is forbidden to donate blood in informal institutions.