Since one of the more important functions of the kidneys is to eliminate toxic waste from our body through urination, adequate water supply in the body is of utmost importance. When we are in a semi-dehydrated state, our body’s instinctive reaction is to hold on to whatever water there is in the body in order to survive. When this occurs, the body’s toxic wastes are not eliminated regularly and begin to accumulate causing the liver to help out with the overload. When this happens, the liver fails to perform one of its tasks efficiently: burning stored body fat for energy. The body then becomes unable to burn body fat as efficiently as normal.

A lot of people refrain from drinking plenty of water because of the misconception that it will lead to fluid retention. The exact opposite is true. Dehydration causes the body to hold on to all the water that’s available in the body. Consuming plenty of water causes the body to feel hydrated and enables the kidneys to flush the water out as they normally and regularly do, resulting in less water retention.

The general rule for water intake of 8 to 10 eight ounce glasses (1920ml to 3000ml) of water daily is only a guideline. A more accurate calculation of daily water requirements should also include physical activity levels and caloric expenditure in order to achieve a more realistic estimate of individual water needs.

To get a more accurate estimate of your particular water needs, it is recommended to factor in your activity level using your daily calorie expenditure (DCE). The recommended dietary allowance for water is 1.0-1.5ml per kilocalorie expended per day. The following chart lists the required water amount based on your daily calorie expenditure.

Calories
Expended Daily H2O
Requirement
2000 2000 to 3000 ml
2500 2500 to 3750 ml
3000 3000 to 4500 ml
3500 3500 to 5250 ml
4000 4000 to 6000 ml
4500 4000 to 6375 ml
5000 5000 to 7500 ml

Using this formula, a 200 pound man with a daily calorie expenditure (DCE) of 2800 calories daily needs a minimum of 2800ml to 4200ml of water every day. The eight to ten glasses (1920ml to 3000ml) of water guideline should be used as the baseline minimum regardless of daily calorie expenditure.

Never rely on thirst as an indicator or signal to drink water; we feel thirsty when we are already dehydrated, therefore, continue drinking water throughout the day even when you are not thirsty. If in doubt, drink more water, you can never drink enough.

Make it a habit to drink water all day long, especially before, during and after your workout program.