The primary reason we need to eat food is to provide fuel for the body.

Before I start on how fat is burned (or broken down), let me first explain a few terms in the process of converting food to energy: ATP: Adenosine Tri-Phosphate is energy. It's what the body uses as fuel at the cellular level. It can be produced using oxygen (aerobic), or without the presence of oxygen (anaerobic). Glycolysis: An anaerobic process where glucose is converted to pyruvic acid. Pyruvic Acid: If oxygen is available it is converted into acetyl CoA. If no oxygen is available it is converted into lactic acid. Acetyl CoA: All this potential energy can only be achieved if it enters the Krebs Cycle, and to do this it must first be converted in to acetyl CoA. Krebs Cycle: This is an eight step cycle that removes hydrogen and carbon-dioxide. It also produces a small amount of ATP. The Electron Transport Chain: The final process in the breakdown of foods. This is where most of the ATP is formed. Burning fat: There are a number of fats in the body but it's the triglycerides, that are usually converted to energy. The triglycerides come from both stored fat and diet. This single triglyceride will eventually produce 441 ATP molecules. When compared to the 38 ATP that are produced by glucose. Step 1: The break-down of triglycerides To be used for energy a triglyceride needs to be broken down into its basic units: one molecule of glycerol and 3 molecules of fatty acids. This process is called Lipolysis. Step 2: Conversion to acetyl CoA Although they both have the same outcome, the glycerol and fatty acids each follow a different path. Their goal is to enter the Krebs Cycle, but first they must get converted to acetyl CoA. Glycerol to acetyl CoA Glycerol, which is a basic sugar, follows the glycolytic pathway (glycolysis). During this process it is converted into pyruvic acid. For entry into the Krebs Cycle, the pyruvic acid must be converted to acetyl CoA. Step 3: One carbon is removed from the pyruvic acid and released as carbon dioxide, which is released from the cell and exits from the lungs. Hydrogen atoms are removed and will later exit be used to produce more energy. What's left is called acetic acid, and it is combined with coenzyme A to form Acetyl CoA. Step 4: The Krebs Cycle At this point both the glycerol and the fatty acids have been converted to Acetyl CoA and are now ready for the Krebs Cycle. As the Acetyl CoA is broken down, carbon-dioxide and hydrogen are removed. Once again the carbon-dioxide exits the body from the lungs. However, the hydrogen moves on to the final stage. Step 5: The Electron Transport Chain The Electron Transport Chain is the final process in the break down of food. Each of the hydrogen molecules that were removed during the previous processes have been transported here. They now combine with oxygen to form water, with the resulting energy from this reaction causing the formation of ATP. I made it into a 5 step cycle instead of 8 steps. The rest of the cycles deal with waist. Thanks.L.G. #lgfitnessmessiah