The Incredible Shrinking Fat Cell - What Really Happens When Body Fat is Burned?

The Incredible Shrinking Fat Cell - What Really Happens When Body Fat is Burned?Earlier this week someone in our discussion forum wrote, "Ihaven't "LOST" any fat... I know EXACTLY where it went! Igot a chuckle out of that because I "got" the joke, buttruth is, most people really don't know how fat cells work,how the fat burning process takes place or where the fatgoes when it's burned . It's actually quite a complexbiochemical sequence of events, but I'll explain it assimply as possible, so by the end of this article, you'llbe a "fat burning" expert!When you "lose" body fat, the fat cell (also called anadipocyte) does not go anywhere or move into the musclecell to be burned. The fat cell itself, (unfortunately)stays right where it was - under the skin in your thighs,stomach, hips, arms, etc., and on top of the muscles -which is why you can't see muscle "definition" when yourbody fat is high.Fat is stored inside the fat cell in the form oftriaglycerol. The fat is not burned right there in the fatcell, it must be liberated from the fat cell throughsomewhat complex hormonal/enzymatic pathways. Whenstimulated to do so, the fat cell simply releases itscontents (triaglycerol) into the bloodstream as free fattyacids (FFA's), and they are transported through the bloodto the tissues where the energy is needed.A typical young male adult stores about 60,000 to 100,000calories of energy in body fat cells. What triggers therelease of all these stored fatty acids from the fat cell?Simple: When your body needs energy because you'reconsuming fewer calories than you are burning (an energydeficit), then your body releases hormones and enzymes thatsignal your fat cells to release your fat reserves insteadof keeping them in storage.For stored fat to be liberated from the fat cell,hydrolysis (lipolysis or fat breakdown), splits themolecule of triaglycerol into glycerol and three fattyacids. An important enzyme called hormone sensitive lipase(HSL) is the catalyst for this reaction. The stored fat(energy) gets released into the bloodstream as FFA's andthey are shuttled off to the muscles where the energy isneeded. As blood flow increases to the active muscles, moreFFA's are delivered to the muscles that need them.An important enzyme called lipoprotein lipase (LPL), thenhelps the FFA's get inside the mitochondria of the musclecell, where the FFA's can be burned for energy. If you'veever taken a biology class, then you've probably heard ofthe mitochondria. This is the "cellular powerhouse" whereenergy production takes place and this is where the FFA'sgo to be burned for energy.When the FFA's are released from the fat cell, the fat cellshrinks and that's why you look leaner when you lose bodyfat - because the fat cell is now smaller. A small or"empty" fat cell is what you're after if you want the lean,defined look.It was once believed that the number of fat cells could notincrease after adulthood, only the size of the fat cellscould increase (or decrease). We now know that fat cellscan indeed increase both in size (hypertrophy) and innumber (hyperplasia) and that they are more likely toincrease in number at certain times and under certaincircumstances, such as 1) during late childhood and earlypuberty, 2) During pregnancy, and 3) During adulthood whenextreme amounts of weight are gainedSome people are genetically predisposed to have more fatcells than others and women have more fat cells than men.An infant usually has about 5 - 6 billion fat cells. Thisnumber increases during early childhood and puberty, and ahealthy adult with normal body composition has about 25 to30 billion fat cells. A typical overweight adult has around75 billion fat cells. But in the case of severe obesity,this number can be as high as 250 to 300 billion!The average size (weight) of an adult fat cell is about 0.6micrograms, but they can vary in size from 0.2 micograms to0.9 micrograms. An overweight person's fat cells can be upto three times larger than a person with ideal bodycomposition.Remember, body fat is basically just a reserve source ofenergy and fat cells are the like the storage tanks. Unlikea gas tank in your car which is fixed in size, however, fatcells can expand or shrink in size depending on how"filled" they are.Picture a balloon that is not inflated: It's tiny when notfilled with air - maybe the size of your thumb. When youblow it up with air, it can expand 10 or 12 times it'snormal size, because it simply fills up. That's whathappens to fat cells: They start as nearly empty fatstorage "tanks" (when you are lean), and when energy intakeexceeds your needs, your fat cells "fill up" like balloons(not a pretty picture, is it?)So you don't actually "lose" fat cells, you "shrink" or"empty out" fat cells. Since fat cells can not only getbigger, but also multiply, you have be diligent andconsistent in your fat-burning lifestyle because even afteryou shrink your fat cells, the cells are still there (inyour thighs, lower abs, etc), waiting to be filled up withmore fat again, if you're not careful...So stay active to keep burning fat and avoid consuming morecalories than you burn, and your fat cells will get shrunkand stay shrunk!About the Author:Tom Venuto, CSCS, CPT, is a natural bodybuilder, certifiedpersonal trainer and author of "Burn the Fat, Feed TheMuscle," which teaches you how to get lean without drugs orsupplements using secrets of the world's best bodybuildersand fitness models. Learn how to get rid of stubborn fatand increase your metabolism by visiting:http://www.burnthefat.com andhttp://www.burnthefatinnercircle.com