Researchers from Berlin's Franz-Volhard Clinical Research Center in Germany report that water consumption increases the rate at which people burn calories. After drinking approximately 17 ounces of water, the metabolic rate of the participants of the study increased by 30%.

The kidneys need sufficient water to function properly, and when they are water deprived, the liver is overworked. One of the functions of the liver is to metabolize stored fat into energy, and cannot perform efficiently when compensating for the kidneys. The liver then metabolizes less fat which remains stored in the body. Studies have shown that a decrease in water intake will cause fat deposits to increase, while an increase in water intake can actually reduce fat deposits.

The human body consists of anywhere from 55% to 78% water depending on body size. To function properly, the body requires between one and seven liters of water per day to avoid dehydration. The precise amount of water required depends on the level of activity, temperature, humidity, and other factors. Original recommendation for water intake in 1945 by the Food and Nutrition Board of the National Research Council read: "An ordinary standard for diverse persons is 1 milliliter for each calorie of food".

Dehydration can lead to joint pain, backache, fatigue, depression, headaches, muscle cramping, and in severe cases of dehydration respiratory problems, vomiting, diarrhea, and unconsciousness can occur.

Water acts as a lubricant, protecting our joints and other body parts. Water is also good for your complexion, as it flushes out impurities in your skin. Water may also help to reduce sagging skin after weight loss by hydrating the skin and restoring elasticity. Good hydration will also improve muscle tone and increase the effectiveness of workouts.

The general rule is to drink 8 glasses of water, spread evenly throughout the day, and increase by 1 glass for every 25 lbs of excess weight. With active people, the intake of water should be increased accordingly to the level of activity.
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