Answer: The short answer is no. Drinking more water is not a weight loss program. Excessive fluid intake will not enhance fat loss. In fact, there is a real danger to excessive fluid intake called hyponatremia or water intoxication. This occurs when the body’s plasma sodium levels become diluted. Symptoms include nausea, vomiting, and headache and can lead to a coma if not addressed. In 2007 a woman died as the result of excessive water intake related to a radio station contest, bringing public attention to this relatively rare occurrence.
On the flip side, not taking in enough water can impair every function in the human body to some degree. Poor fluid intake is still the number one performance obstacle for athletes. As little as a 2% decrease in total body water can decrease performance by as much as 10%. Thirst can be a poor indicator of fluid needs, especially in the elderly and adolescents. Adding to the risk of dehydration is the fact that water is lost in the body at a rate greater than it can be drunk and absorbed during activity. There are many factors that affect fluid needs, but 8-12 cups of accumulated fluid (from food and beverage) a day will meet most needs. Keep in mind that all fluids and even food provide water. If you sweat a lot, exercise often and work/workout in hot, humid conditions, your needs will be greater.