A weight difference of about 0.5kg to 1.5kg before and after going to bed is normal, and the exact weight difference should depend on the individual. Generally speaking, the weight of normal people after waking up in the morning, before breakfast and after urination and defecation is the lowest value of the whole day. During sleep, the body’s energy is also being output and consumed. During sleep, there is no energy intake, which means that consumption is greater than intake. There is no other energy intake by the body until breakfast. After the morning urination and defecation, the weight at this time belongs to the lowest weight of the whole day. Generally speaking, the weight difference between before and after bedtime ranges from 0.5kg to 1.5kg, which is normal. If the weight difference between before and after sleeping is too big or there are other uncomfortable symptoms, you should go to the hospital in time to avoid delaying your condition.