How much weight fluctuation is normal for the human body in one day?

The normal daily weight fluctuation of a person is about 1-3kg, which is within the normal range.
Because everyone's daily dietary composition is different, the amount of food they eat is not very constant, and the amount of water they drink and the amount of exercise they exercise have a certain impact on their weight. It is best to set a fixed time every day when weighing, which can be after using the toilet in the morning, before meals, or at night. In short, it is necessary to set a fixed time for comparability.
Please fully understand the daily weight fluctuations. If the weight continues to decline, for example, if the weight drops more than 10% of the original weight every month, please pay attention to whether there are pathological factors. In addition to deliberate weight loss, please pay attention to whether there are diabetes, hyperthyroidism, tuberculosis, tumors, and gastrointestinal diseases that can lead to weight loss.