There is one main reason why our weight can change so rapidly from day to day. It’s all to do with changes in water balance. Remember the human body of an adult is about 60% water yet water is always lost from the body in some form; breathing, sweating or passing it. Usually a small percentage of water is lost every day but if the ambient temperature is high its possible to lose a little more.

All water losses are replaced by drinking and eating however, how well we balance the water coming out with water in often differs between individuals and from day to day. For example, someone may not drink or eat as much as the day before, or they may participate in a long, strenuous game where they sweated a great deal. It’s possible that these daily choices could affect weight by a few pounds. In extreme cases it may be as much as ten pounds, although it should be stressed that trying to lose water to drop weight is NOT recommended!

More complex ways in which the body can gain weight quickly is through consumption of high amounts of certain nutrients. Sodium is a classic for water and weight changes. Sodium is present in salt and because salt is present in 99% of processed foods we can easily consume too much sodium. The caustic effects of excess sodium need to be buffered so the body retains water to compensate for this. The result is we may gain up to an extra 5 pounds because of excess sodium. *

When additional protein is deposited inside muscle cells (as in muscle building) the cells absorb four times the amount of water to hold it. On eating lots of complex carbs the muscles store it as glycogen and this retains three times its weight in water. There are also a few supplements that can cause gains in water weight, the energy boosting Creatine is just one, learn more about supplements here Diet Supplements Revealed

In fact, many diet plans are based on the fact that lowering intake of any of the nutrients mentioned above will effect water balance, and thus weight will be lost rapidly. That’s why some diet plans can guarantee rapid weight loss because its just water loss. The problem is water is easily gained after a diet plan has ceased as water balance is simply re-established!