Some people gain weight after donating blood, which seems to have a tendency to get fat, mistakenly thinking that getting fat is caused by donating blood. In fact, this idea and statement is very unscientific. After donating blood, if you pay too much attention to rest and nutrition, the energy you consume will greatly exceed the energy you consume, which will help your body gain weight. This is an understandable normal phenomenon. As long as you pay attention to diet regulation, strengthen activities and exercise, you can gradually return to normal weight.