I have read that there can be something like a water intake imbalance. The person requires excessive amounts of liquid. The person whom I suspect has such a problem drinks excessive amounts of sweet drinks very often in place of eating food, insisting that she is not hungry at all but needs to drink. At a potluck of very healthy delicious food, she ate very little which included something like lasagna and cake, but drank a 16 oz. bottle of sugared drink, then finished with four 8oz. cups of Pepsi or Coke. That is 48 oz. of sugared liquid just at one mealtime, while everyone else is enjoying food. She often refuses food, then proceeds to drink. Is this a symptom of some known kind of health problem? I will appreciate your answer.