Water & Weight Loss

Below is an excerpt from Part Two of

The 2004 Multi-Diet

by Anderson A. Anonymous, M.D., Ph.D.

Background

It is interesting to note that some water is actually created from hydrogen and oxygen by your body’s metabolism. The process of burning virtually any organic substance produces water, and the metabolic “burning” of carbohydrate, fat, or protein is no exception.

However, the amount of water you create this way is insignificant compared to your daily needs. About 13 ml of water is formed for every 100 Calories burned. This works out to about 200—300 ml per day for the average diet or about one cup of water created for each 2000 Calories burned. Obviously, this is not very significant amount compared to the amount your body requires each day.

The amount of water you will need from food and drink varies with the amount of water you lose. And this loss can vary enormously. One of the main functions of water in the body is to carry off waste materials. The kidneys can change the amount of water used for this purpose quite considerably by concentrating the urine either more or less. But there are limits to their ability to do this and the waste elimination function cannot be neglected for any length of time without producing serious problems, as I’ve described.

Under “normal” circumstances, you can expect to lose about 4% of your body weight in water daily. This is the amount that must be replaced. (Use the calculation table below for a very approximate estimate of this requirement.)

A quart has 32 oz or 946 ml

Note that you do not necessarily have to drink the amount of water you calculated above. Most food has a lot of water in it and this water will take care of a lot of your real need. For non-dieters, typically about 45% of the needed replacement amount will come in the food they eat. But dieters—who are not eating much food—will usually need to drink a much higher percentage of total amount lost—another reason to pay conscious attention to the water factor.

About one half of the amount of water you lose per day is nearly unnoticeable because you lose it through your skin and in breathing. This is the amount you lose in an environment cool enough to prevent visible sweating. If you are doing heavy work in a hot or dry environment, or at high altitudes, you can lose much more—up to ten times more—just from your skin and lungs. Sweating, as you know, is the body’s way of using water to eliminate unneeded heat. About 600 Calories of heat is eliminated for every quart (liter) of perspired water.

Because the need for water is so variable depending on the above and other factors, no RDI for it has been set. However, there are some guidelines. The rule-of-thumb is that you should get approximately one to one-and-a-half milliliters of water for each Calorie (kcal) that you eat. For example, if you eat 2000 Calories per day you need to get 2000- to 3000-ml (2–3 quarts) of water per day. Up to 45% of this will probably come in the food you eat.

It is important for dieters to pay conscious attention to getting enough water. Do not depend on thirst to tell you when to drink. The thirst sensation does not typically kick in (activate) until you have lost about 1.5–2.0 quarts (or liters) of water.

This amount of water weighs 3–4 pounds (about 1.5–2 kg). You could lose it in one day (yippee!J) and gain it all back the next (gloom…L)—another good reason to distrust both the scale and all those diet plans with great-looking models that breathlessly rave about how “I lost 8 pounds in a week!!!”.

It is interesting to note that water can be toxic in huge amounts. I am not referring to drowning (although that is obviously toxic J). It is apparently possible—though extremely rare—to ingest water so fast that the kidneys can’t get rid of it fast enough. The known symptoms of this are gradual mental dulling, confusion, coma, convulsion, and death.