Burning fat does produce waste because fat is physical matter. Things that take up space and have volume are called matter. There are three basic types of matter -- solid, liquid or gas. They can change form but cannot be made or destroyed. You are made of and are surrounded by matter.
Carbon dioxide and water are the waste products of fat burning. Your body changes fat into smaller, usable molecules of fatty acids and glycerol -- a sugar alcohol -- by mixing it with bile acids and enzymes. The conversion takes place in your small intestine where these smaller molecules flow into and in between cells. Fat is used throughout your body, including your stomach, intestines, brain, glands and skin.
Burn the Fat
The metabolism of fat allows every cell in your body to use it effectively. After fat is changed into fatty acids and glycerol and has traveled through cell walls into blood vessels, the remaining carbon dioxide and water flow into your lungs or kidneys where they are filtered out of your body. If they're not removed, they will damage the body.
The Busy Life of Fat
Muscles use fat as an energy source. Fat has the greatest number of calories -- 9 calories per gram -- compared to other nutrients you consume. A gram is about the weight of a paper clip. Alcohol takes second place at 7 calories per gram and carbohydrate and protein tie at 4 calories per gram. Fat plays a key role in the immune system, brain health and the absorption of fat-soluble vitamins A, D, E and K. Fortunately, fat makes food taste good and helps you feel full after eating too.
The Best and the Worst
Not all fat is the same. The healthiest fats are monounsaturated and omega-3 fatty acids and are found in olive, canola and peanut oils, avocado, nuts and seeds, fatty fish like salmon, tuna, mackerel, herring and sardines. They can help lower bad cholesterol levels, your risk for heart disease and stroke and keep your brain healthy.
The unhealthy fats are saturated and trans fats found in meat, chicken and turkey skin, coconut and palm oils, lard and high-fat dairy products, some bakery products, breaded foods, hard margarine and vegetable shortening. They can raise your bad cholesterol and raise your risk for heart disease and stroke. Large amounts of saturated fat may cause inflammation in the brain and may play a role in age-related memory loss. The type of fat you eat determines whether it will be helpful or potentially harmful to your body. Waste will be produced regardless of what type you eat.