When you lose weight, the fat stored in your body is metabolized and converted primarily into carbon dioxide and water. About 84% of the fat you lose is exhaled as carbon dioxide through your lungs, while the remaining 16% is converted into water, which leaves your body through urine, sweat, and other bodily fluids
. Here is a more detailed explanation of the process:
- Fat cells store energy in the form of triglycerides, which are made up of carbon, hydrogen, and oxygen atoms.
- When you create a calorie deficit (burn more calories than you consume), your body breaks down these triglycerides into fatty acids and glycerol.
- These molecules enter your bloodstream and are transported to cells where they undergo chemical reactions with oxygen (oxidation).
- This oxidation process releases energy your body uses for various functions.
- The byproducts of this chemical breakdown are carbon dioxide (CO2) and water (H2O).
- The carbon dioxide is expelled through your breath, and the water is excreted via urine, sweat, and exhaled air
In summary, the weight you lose literally leaves your body mostly through your lungs as carbon dioxide, with the rest leaving as water through sweat and urine. This means that when you "lose weight," the fat is not destroyed but transformed and expelled primarily by breathing it out
