Where Does The Fat Go? Have you ever wondered?! :))
We burn it as energy (kind of like we burn wood for heat). However, the fat cell doesn't disappear - it just shrinks.
Unlike brain cells, fat cells stay with us forever (even when we lose weight). While it's true that the number of fat cells we have is pretty much constant after the age of 20, prolonged weight gain will likely result in the development of new fat cells. In one study, participants gained new fat cells after only 8 weeks of overfeeding.
As such, prevention of weight gain (as opposed to weight loss) should be the primary goal because once we have those extra fat cells; we are pretty much stuck with them for life.
Don't get me wrong, weight loss is important, but when it comes down to it - it's more important to prevent further weight gain. Meaning, if I had to choose between losing weight via some fad diet only to go on and regain that weight plus some versus simply maintaining my weight, I'd choose maintaining my weight to avoid risk of gaining new fat cells (and other inflammatory processes that will occur inside the cell). Master weight maintenance via a healthy lifestyle first. The rest will come on its own.
The other thing to mention is this, it is for this reason that someone who was overweight and loses weight, will have to work a little harder than someone who doesn't have a history of obesity.
Although their weights may be identical now, the formerly overweight individual has more active fat cells. These cells may increase hunger or interfere with metabolism some, so overweight people do have it harder than normal weight people. They may gain weight while the others maintain weight - despite an identical calorie intake. So, no, they aren't always just eating too much. They may have been overweight children.
This is another reason for everyone to focus on prevention. Especially with our children. Let's set them up for success!