I read everywhere that you have to drink at least 8 glasses of water in a day. But is it really necessary? So to help you answer this common query we have Ms Rina Baliga Nutritionist Mumbai shedding light on why we feel thirsty. Also read about warm water vs. cold water which is better to drink? Why do we feel thirsty? Water makes up for about 70% of the body weight. So if the water volume of the body falls below a certain threshold or the osmolyte concentration becomes too high the brain signals thirst. You feel thirsty when