T Nation

Water Weight

Why is it that when you diet that the first pounds you lose are due to water weight (even when drinking more water than usual)? I realize this is probably a question many people already know the answer to, but I have asked a couple different people and everyone seems to have a different answer.


I would imagine it’s a defense mechanism of your body in a way. Also- your body naturally retains water to aid in digestion and nutrient absorption. If you are taking in less food, it doesn’t need to retain as much water.

I don’t know the scientific reason though. Use google and look it up.

Well you usually drop carbs down when dieting. drop lots of the simple sugars etc, meaning your excess glycogen stores get depleted and well along with that water do to for every gram of glycogen stored you have 3-4 grams of water.

A neat fact I learned is that for every lost kilogram of even amounts of lean and fat mass, about one liter of water is lost.

One thing to be aware of is that lean mass holds more water than fat mass.

My first guess would be an osmotic pull, but I’m only guessing.