Hi. I'm a complimentary health practitioner: I am a health dowser/essential oil therapist.
Dowsing is the use of energy to read other energy and determine what is the best way to rebalance it.
This includes diet, fitness, lifestyle and general health.
There is no blanket answer on the water question because everyone is different.
I have some clients who, if they drink 2-3 litres of water a day resemble the michelin man - but if they are dowsed to need 1.5 litres of water find that they are healthy, the system is flushing through and they are hydrated. There is also the timing. Some people can drink early in the morning - others cant. Some people can drink late into the evening - others cant drink past 7pm say, or they retain the fluid, not flush it through. Everybody is different and it is finding the level that suits you.
This goes for food, both in type and when you can eat it - not everyone is the same so its no good saying you need 5 portions of this that or the other when your energies read that at this time you can only cope with 3. Some systems need 9 portions of the daily recommended intake of fruit and vegetables.
Dowsing is able to determine your food and water intake to suit you, your energies and your lifestyle.
So saying a blanket 8 glasses a day is silly. A sports car doesnt use the same amount of fuel as a small family saloon does it?
The same principle applies.