How to lose 1.5 kg overnight???

Diuretics should not be used - weakness and lethargy are guaranteed, and you will have to run to the toilet all night instead of sleeping.

Then we do this:

For 250 ml of kefir take 1/3 of sugar and drink before bed. In the morning you will lose 1-1.5 kg of weight.

How is that possible? If you haven't consumed dairy and sugar for a long time, then this mixture is heavy carbohydrates, and a lot of energy is spent on digesting them.
But this works once every 2 months, and it cannot be used more often, only in an emergency.

Athletes sometimes use this method to lose weight before competitions.