Water
Water promotes metabolism, which is very important to stay in good shape.
If the body receives a sufficient amount of water, the person will feel more energetic and cheerful. Easily copes with stress, improves his thinking and brain function.
One of the main properties of water is that it protects the body from exhaustion. When a person loses 6-10% of water, he starts having headaches and loses the ability to think logically, so I recommend that you drink as much water as possible.
Keep in mind that this recommendation only applies to those who do not suffer from high blood pressure or other health problems, otherwise agree with your Doctor.