> The guiding principle behind the new hydration index is that some fluids last longer in your body than others Is that all there is to it? Could it not happen

> The guiding principle behind the new hydration index is that some fluids last longer in your body than others Is that all there is to it? Could it not happen that some drink caused the water supply in the body to decay as normal, but then continuing to even lower levels than before, for example? > Lawrence Armstrong, a hydration expert One wonders how there can be such a thing as a hydration expert if not even these basic things have been known until now. > But don’t forget that milk has many more calories than water, so don’t overdo it, either. A bit beside the point, perhaps: What caloric content is there in water? Can it be said to have any at all? It makes you think about how to define it, really. On the one hand, we don't typically think of the energy as coming from the water, but in the other hand, water must be present for us to extract the energy from other molecules. In a situation where energetic molecules (but not water) are already present, then, it is the consumption of water that causes an increased amount of energy to be made available to our bodies. Similarly, a battery contains energy, but not until we add cables to connect it do we get access to it. In a sense, it is the addition of the cable that contributes the energy.