Thirst and Hunger are completely different feelings though aren’t they? Surprisingly enough both, hunger pangs and thirst, actually trigger the same brain responses, the hypothalamus, which is responsible for controlling hunger and thirst, responds in a similar way whether hungry or thirsty!
Numerous factors influence the hypothalamus when your body is hungry or thirsty. Those factors account for what we eat, as well as how our diet is influenced by social context and lifestyle/work. For example, we are always accounting for things like the sort of way food is served, or the quantity of liquid that we expect in a traditional version of a dish. Then there’s the actual composition of a meal or drink. Nearly all foods contain some water which is metabolized by our bodies and the water content is released, which in turn mimics how we process water when we’re drinking it in its pure form.
So where is the confusion? Imagine you are about to have a yoghurt, how does your hypothalamus react? In one way its a solid food, nutrients etc are harvested from it, which should satiate your appetite, but its almost a liquid too. Has the yoghurt solved your huger pangs or your feelings of thirst? Here lies the issue and the grey area as the hypothalamus gets confused.
One more example would be the consumption of soup out of a cup! Your'e consuming a food, in liquid form, out of a vessel that is used for liquids ordinarily. So will the soup satiate your hunger, your thirst, both or neither?
Often all the signals we receive from our hypothalamus are interpreted by us as feelings of hunger. Studies actually show that thirst motivations are more intense and felt constantly through the day compared to hunger. As humans can only survive for about 5-7 days without water and our composition is 75% water its hardly surprising that we are hardwired to demand water more so than food. We can go up to a month without food and survive though.
So the big danger is confusing thirst for hunger by mistake. In an effort to remain dehydrated the body will push you towards food when you actually need water.
Just remember that over eating has a vast array of detrimental effects on our health, over drinking will just mean more trips to the loo! Drink more water lose more weight.