What Happens to Weight?

"Input = output + accumulation" (conservation of matter).

• Body weight gain comes from substances eaten or drunk.
• Body weight loss comes from substances that are excreted (solids, liquids and gases).
• Accumulation is the difference between these two.

Say for example, I weigh 160 lbs, if I consumed a pound of food and after 10 minutes (I have not been to the toilet yet) I go onto the scale, will my weight be 161 lbs.?

Slightly under. The body loses weight continuously by evaporation of water from the lungs, and carbon dioxide, every time exhaling takes place. Water and carbon dioxide are the waste products from http://en.wikipedia.org/wiki/Respiration.

160 sounds good enuff to me!* Think about something else!!

*My legal advisors say this depends on your height and many other factors and I shouldn't make darned stupid sweeping statements that could easily lead to your death or my imprisonment.

Body mass can neither be created or destroyed. When you lose weight it just hops over to someone else. When they get skinny, you get fat.

(Based on a lifetime of scientific observation.)

OK, let me bring this to our environment. Say I grow a tree. The tree became big. Isn't it that weight had been created? Now, I will cut a branch, let it dry, then burnt it, is it not weight had been destroyed or has it been transferred to another?

The weight hasn't been created so to speak. The nutrients and water that the tree needs to grow have been absorbed from the environment arouond it. So the "weight" of the surroundings will go sown as the trees weight goes up. Then it rains and the surrounding area gains "weight".

When you chop off a branch and dry it then the water is evaporating into the atmosphere. You are not destroying weight .

I find the way these questions are phrased rather odd. Think of it as gaining or losing mass. Weight is the wrong word for a start. If you have a backpack and I fill it with sand then you have gained mass then if you take it out you have lost that mass. Forget about destroying it and such like. I don't know how to phrase it any simpler than that cos it is a very simple idea which I can't believe I have spoken about so much.

Thank you for the kind explanation. I appreciate it.

So where is this skinny bugger I want give him his fat back. I am off now to get a burger and a couple of beers. Anyone want the calories?

Surely you have experienced rapid weight loss when you have a had a heavy booze session the night before and in the morning you go to the toilet. Sometimes it feels like I can float after I have had a major evacuation.

Please keep in mind the calorie.

Simple mechanics, input port larger than output port. Good design for nomadic existence where food is intermittent, bad design for times when food is plentiful.

Here is a simplified explanation.

You gain weight when your calory intake (food) is not "burned" completely in your body. Most of the residual calories that is not burned becomes body fat. This is how you gain weight.

You loose weight when you burned more calories then your calory intake. Say, you take 200 calories for breakfast and you burned 250 calories for biking to the office. The body will take the 50 calories from your body fat. This is how you loose weight.