Where Do Fat Cells Go When You Lose Weight?

Dieting is a preoccupation of many people, especially because two-thirds of all Americans are overweight, according to a report from the Centers for Disease Control and Prevention. If 160 million Americans lost 10 lbs. each, they would be missing 800,000 tons of fat. The laws of the conservation of mass say that mass can't disappear, although it can change its form and location.

Significance

Fat cells store energy in the form of triglycerides, with one glycerol molecule and three fatty acid chains each. When you consume more energy than you use on a daily basis, the extra calories are stored as triglycerides in fat cells. When you use more energy than you consume on a daily basis, fat cells break down triglycerides and release the components into blood vessels to be used as energy. The more energy you consume, the more of it is stored in your fat cells. Therefore the fat cells get bigger. If you consume fewer calories than you use, then the body pulls triglycerides from fat cells for use as energy, and therefore the fat cells get smaller.

Function

When fat cells release glycerol and fatty acids, the liver absorbs glycerol to make energy and fatty acids are used by muscles for energy. Inside the liver or muscle cells, glycerol and fatty acids are further broken down into carbon dioxide, water and heat, as well as adenosine triphosphate. ATP provides the power for all activities in your body requiring energy. Carbon dioxide is exhaled by the lungs, heat produced from this process keeps the body warm and water is excreted as urine and perspiration.

Effects

Smaller fat cells are healthier, and produce necessary hormones, such as adiponectin, which helps fight diabetes and heart disease. In obese people, fat cells produce less of the good hormones and may produce too much of harmful hormones, such as estrogen that can stimulate cancer growth. Large fat cells also contribute to insulin resistance, a precursor to diabetes.

Considerations

The number of fat cells in the body doesn't decrease with weight loss; the cells just get smaller. But the number of fat cells you have can increase. A healthy person with normal weight can have 10 billion to 20 billion fat cells. The number of fat cells you have is evidently established in teen years. Generally the number of fat cells remains constant in all body types, according to Susan Fried, director of the Clinical Nutrition Research Unit of Maryland at the University of Maryland School of Medicine in Baltimore. If you overeat hard enough and long enough, your fat cells will trigger immature fat cells to develop into maturity, increasing the total number, Fried says.

Benefits

Losing weight is difficult, but it is better for your health. Small fat cells are healthier and produce healthy hormones. Large fat cells slow down on production of healthy hormones and become a health risk, leading to diabetes and heart disease.