We often hear of the general 'drink 8 glasses of water a day'. Yet, we are all different - differing sizes, differing activity levels, and differing diets - and therefore in need of differing quantities of water. The macrobiotic approach would be tailored to each individual - we all have different conditions. On this basis, it is often suggested that you 'drink when you are thirsty'. This also allows us and teaches us to get more in touch with our bodies, as opposed to having the standard 2 litre bottle of water on our desk that we MUST finish. Obviously, if you are eating more steamed or blanched vegetables, as opposed to baked flour products, you would require less water.
Drinking excess water also places additional burdon on the kidneys. Yes, the kidneys will flush out the excess, but they do 'work' to do this. This could result, in time, in overworked and weakened kidneys.