system
Given the following post, respond as if you're commenting on Reddit:
human
How does the body eliminates fat tissue?

I have been changing my life style, eating habits and exercising more. And it made me wonder, how does my body eliminates the fat issue previously stored?
gpt
It depends on what you mean by fat tissue.

Your fat, like the fat in your belly, is made up of huge adipocytes 100x+ more voluminous than fibroblast cells. These adipocytes are tethered together and packed densely with capillaries and larger vessels wending through. When you lose weight due to exercise or eating habits these adipocytes shrink in size (they're undergoing lypolysis). Basically, the lipid they've been storing is being burned up, so they shrink.

If you continually run a calorie deficit then eventually, and here the research is incomplete, your fat cells will decrease in number as well. The thought is that there is a certain turnover rate of fat cells, atomic labeling studies show ~10% of adipocytes turn over every year. So, unless they are replaced at the same rate, you will eventually decrease the number of adipocytes you have. Eating certain foods, and having a calorie excess, can lead to more pre-adipocyte stem cells to decide to differentiate into adipocytes. Just so, if you're running a deficit fewer pre-adipocyte stem cells will differentiate into adipocytes. So, over time, you'll lose cells naturally and they won't be replaced if you are restricting your calorie intake. 

So you lose fat by the cells shrinking, and by the cells dying.