When someone loses weight where does it go?

[Jargan]

ATP (energy production) doesnt involve fat in any way, shape, or form, at all...ever.
Its Glucose + Oxygen to yield CO2+H20 and ATP. Fat is a lipid while glucose is a carb. Lipids are stored energy and are only burned off after you exhaust all of your Sugar (Carbs)

Some fats are modified and inserted into the glycolysis pathway and will eventually yield ATP.

Beta oxidation of fatty acids yields NADH/FADH2 and Acetyl-CoA. The Acetyl-CoA is fed into the electron transport chain to yield ATP. Similarly, glycerol is converted to glyceraldehyde-3-phosphate, which is a component of glycolysis.

This is way beyond the scope of the original question, though. Energy sources are stored in your body until they are needed. Then they are converted into usable forms, and broken down or used to generate high energy molecules or electron transporters like ATP, NADH, etc. The mass lost is due to loss of waste products: water, CO2, and unusable forms or fully broken down molecules with no further use to the body.

[staart]

WTF @ people using E=mc^2

This is used in relativistic mechanics. Mass to energy conversion happens NOWHERE in your body.

The human body get's it's energy from breaking down chemical bonds. Mass conservation is in absolute effect. You breathe, sweat, poo and piss everything out you get in.

[assassin8197]

go? it goes everywhere, I guess...

[MagicBanana]

Burned and digested just like food. I would think it is excreted through our pores as sweat too but that would just be a personal guess.

[Ravock]

This thread went full retard on the first page.

[Greed001]

Ahahahahahahahaha I had to take a double take at this thread.

This is a fuck yahoo answers question right here on MMO-Champion.

They went through this in the most basic biology class, dude. Maybe you should pay attention.

[sugarlily]

To fat heaven? >.>

<obligatory image of some lovely bacon, devil's food cakes, carbs etc etc all with halos & wings!!! passionate & dramatic gasp>

hey, i want to go to there!
^^

[Unalorian]

the left over you shit out

Nope. Feces is only the end of the digestive process, i.e. stuff you ate but could not process.

Metabolic waste from cells are dumped in the blood, filtered in the kidneys, and excreted in the urine.

To the OP: check fatty acid metabolism

[pkm]

Burned in the body for fuel or something