There are two forms of fat in the human body:
triglycerides and
fatty acids. Human fat/adipose tissue/love handles – whatever you call it – this is the fat stored as triglycerides. Fatty acids are burned for fuel. Triglycerides are three fatty acids joined together by something called glycerol. Fat enters and exits fat cells as fatty acids (triglycerides are too big to move across the cell membrane – think of a membrane as a cell ‘wall’).
When we talk about fat stored as human fat tissue, we are talking about triglycerides. Inside the fat cell, fatty acids continually ‘cycle’ across the cell membrane and back out again. Fatty acids can be used as fuel during this process (or recycled/stored if they are not used). If three fatty acids are joined by glycerol to form a triglyceride, they can’t get back out of the fat cell until the triglyceride is broken back down into glycerol and fatty acids.