So, I watch what I eat, lose ten pounds, but where does the fat go? Do fat cells go away or do they simply get smaller. If the former, where did they go?
The fat is burned as fuel by your body, the cells themselves shrink but do not go away.
And note that all the carbon that used to be in the fat leaves your body through your nose and mouth. That is, you breathe it out in CO[sub]2[/sub].
America’s obesity epidemic is the world’s greatest CO[sub]2[/sub] sink.
So by overeating, I’m helping to control global warming? 
Until you die.
But for every carbon in fat there are about 2 or 3 hydrogens, which are mostly metabolized to H2O. So, by dieting, you help increase the world’s water supply too.
And those empty cells stick around, just waiting to be filled back up again with Gym Reward Cheesecake.
Fat cells stay unless they are removed by surgery or liposuctoin.
Well, that’s not entirely true. There are drugs, hormones, and other things that can trigger the death of fat cells, but it doesn’t usually happen through diet.
It goes to live with Jesus.
That’s right Jesus has a lot of fat friends 
So if you have lots of fat cells removed by liposuction, let’s say on multiple occasions, does that eventually hinder your body’s ability to store fat, or will it make new fat cells?
The guy who lives down the block that used to play varsity baseball ends up putting it all on. It doesn’t matter though because the fat bastard still ends up fucking your wife.
You will grow new fat cells. My cite: Kerry Katona, who very publicly piled on the weight after her MTV televised liposuction, among other z-list celebrity meltdowns (drugs, bankruptcy, mental illness, unemployment etc).
Fortunately, there are a number of new approaches under investigation to destroying fat cells in vivo, including IR laser and freezing, which may reduce the surgical risks associated with liposuction while allowing fat loss.
Si
I don’t know where it goes, but I am sure it is wearing one sock and has my spare keys and my checkbook.
Keep in mind that liposuction only addresses subcutaneous fat, whereas the fat around your organs (visceral) will stick around. That’s why lipo is cosmetic, it’s supposed to take away what you find hard to reduce through exercise. The visceral fat is probably more important to get rid of for your health though. See here.
Never heard of this - can these drugs be used for weight loss purposes?
Indeed, and I speak as one who went through several uncomfortable weeks of losing visceral fat and actually feeling things rearranging inside as the fat compressing my insides disappeared.
Not sure exactly what drugs Nametag is referring to (a side effect of my Tenofovir HBV antiviral can be subcutaneous fat migration from the mid-section to the upper back), but the answer is almost certainly no. If they have this effect on fat cells, it will be inconsistent, unreliable or unsafe to a greater or lesser degree. Interestingly enough, laser lipo (which uses IR lasers to damage fat cells so that the fat leaks out) is cosmetically effective, but does not cause weight loss. There is a mystery about where the fat ends up that is yet to be solved.
Si
The offspring took a college nutrition class and came away with the factoid that if you can keep a fat cell empty for ten years, it will give up and die. No clue of the veracity on that one.
But, damn. Ten years with little empty fat cells, yearning to be filled. That’s a long time.
It wanders around in large circles, the direction depending upon which leg is shorter. Younger fat will go to the police station and tell them that it’s lost. Nowadays not much fat gets lost, because they have GPS that lets it find your thighs, despite your best efforts to lose it.