Today my friend asked me what's the reasoning behind weight jumps and we couldn't find the answer. So I'm curious and want to find reasoning behind it. In the morning she weights 54kg and 57kg in the evening. Ofc it should be higher in the evening but not that much. Especially if she eats minimum amount of sweets and is not gaining weight over the time, just this spikes. It could be water but it seems too much for me. She is not eating salty foods or any kind of fastfood. Even if it was salt, then why would it jumped back next day. It also shouldn't be glycogen as she has little amount of muscles and carbohydrates intake also isn't that higher than it should be. Could it be hormones because of menstruation? And If, can someone explain why and how are hormones responsible for this? Thanks for your time.