
Originally Posted by
magic32
I'll let the fellas deal with your cycle issue, and just address your primary concern and why the doctor is 100% correct. You are and should be, based on your self-report dehydrated.
Firstly, hydration is more complex than water consumption, it has a lot to do with internal metabolic processes regulated by electrolytes. Water/fluid consumption and dehydration are inversely linked - used to describe two things that are related in such a way that as one becomes larger the other becomes smaller. In this case as water consumption increases (too far), hydration decreases. As with many such relationships there exists what is called the Law of Diminishing Returns, which though often used in economics, it is applicable to much of life. Essentially, it states that a thing can rise, or be good, or increase for only so long before it falls, becomes bad, or decreases. Think back to the bell-shaped curve, a good thing rises, plateaus, and falls. Eating satisfies you, but too much food hurts your stomach, mood, and may even cause vomiting. Two aspirin relieve pain and can stymie a heart attack, but too many aspirin can kill you. Water, and even oxygen are no different.
Water satisfies, nourishes, and removes toxins from the body. Too much water consumed too quickly (as you describe in your habits) depletes a bio-organism of necessary electrolytes: sodium, potassium, magnesium, and calcium. This condition is often called water intoxication, but is clinically known as hyponatremia. Electrolytes function in biological fluid to regulate many metabolic processes such as the flow of nutrients into and waste products out of cells, which includes the absorption and elimination of vitamins, minerals, etc.
By drinking too much water (2.5 gal), too rapidly (within a 24 hr period), you are too rapidly rinsing your regulating electrolytes/body salts out of your system and causing an internal imbalance which results in dehydration. In its broad terms dehydration is thought of as the mere lack of water, but more specifically it is the lack of vital nutrients suspended in fluid.
Moral: Drink less water.