i was told once that your stomach deals with water differently than anything else. Your body needs water and if it gets fed plain water it passes it through your stomach straight to wherever it's needed. As soon as something is added to water it is basically treated like 'food' and so makes you stomach work. For hydration purposes I's say coffee and tea are fine. But I'd say that drinking plenty of plain water (hot or cold) is a good idea and also a really good habit to get into, also for after LT. With our modern eating habits it seems we have unlearned to recognise thirst pangs. In stead our brain translates it into "HUNGER"! And then we eat, when actually our body is craving water. So often, if you drink the water, the hunger should go away.