Thereís an old (and incorrect) idea that adult humans donít make new fat cells. That is, and Iíll discuss this more in a bit, you get born with a certain number of fat cells and you may develop more at puberty or during pregnancy but thatís it; your body doesnít make new fat cells. Everything in that sentence is true except the last statement; even non-pregnant adults can make new fat cells.
Usually this happens when the fat cells you have reach a certain size; that is, they are as full as they can physically be. When this occurs, the actual stretching of the fat cell stimulates the release of factors, such as Angiotensin II, prostacylin and others, which Ďtellí the body to make new fat cells from something called preadipocytes. Preadipocytes are dormant cells, sort of soldiers who wait for the signals to get called into action. When the right growth factors are released, preadipocytes mature into normal adipocytes. Voila! New fat cells.
Those newly formed fat cells can now be filled with yet more fat and glucose. In fact, a new class of diabetic drugs (called TZD drugs) appear to work by stimulating the production of new fat cells, which gives the blood glucose and fatty acids another place to go. Oh yeah, if the new fat cells get too large, your body will keep making more. Iíd note that, in certain situations, the body doesnít make more fat cells and this causes a ton of health problems. Iíd also note that this is only an issue for the extremely obese as a general rule of thumb. There is a weird medical condition (called partial lipodystrophy) where lean adult humans donít have enough fat cells and they can get health problems too. Youíre not one of these people.
Unfortunately, getting rid of fat cells is nearly (but not completely) impossible. Sure, liposuction is always available but, beyond that, eliminating fat cells is very difficult and only occurs under extremely severe conditions. Iíll talk about fat cell apoptosis (death) later on.
If there is a single reason for athletes not to get too fat in the first place, this is probably it: if your fat cells get too big, your body will make new ones. And itís nearly impossible to get rid of the new ones. Obviously, if youíre already very fat, thereís little you can do: youíre pretty much stuck with your fat cells short of liposuction or something along those lines. But if youíre a lean athlete looking to gain weight (and realizing that you must gain some body fat to do it effectively), you should keep a lid on that fat gain. You donít want to stimulate your body to make new fat cells.
What is Body Fat? | BodyRecomposition - The Home of Lyle McDonald