OP, if you drink 2 gallons or more water per day you should have your blood sodium level checked. At 4 gallons per day there is a very good chance your blood sodium is too low.
I have to use a diuretic two or three times a day, and must drink water to keep hydrated, and even then I am only drinking around 2 gallons a day, and my blood sodium level is at the bottom of the good range. In the past I drank more water than I drink now and my blood sodium levels were too low, and I felt light heated sometimes, especially sometimes just after standing up after sitting for a while. When my doctor saw my blood test showed the sodium level below normal he told me to drink less water. And also I have in the past, and continue to put some salt on my food.
If you ever feel light headed, it may be that all the water you are passing through your system is washing away too much of your sodium. So if you ever feel light headed get your sodium blood level tested.
I have to use a diuretic two or three times a day, and must drink water to keep hydrated, and even then I am only drinking around 2 gallons a day, and my blood sodium level is at the bottom of the good range. In the past I drank more water than I drink now and my blood sodium levels were too low, and I felt light heated sometimes, especially sometimes just after standing up after sitting for a while. When my doctor saw my blood test showed the sodium level below normal he told me to drink less water. And also I have in the past, and continue to put some salt on my food.
If you ever feel light headed, it may be that all the water you are passing through your system is washing away too much of your sodium. So if you ever feel light headed get your sodium blood level tested.
