system
Given the following post, respond as if you're commenting on Reddit:
human
Can the body naturally clean fat from arteries?

Assuming one is fairly active and has a fairly healthy diet. 

Or once the fat sets in, it's there for life?

Can the blood vessels ever reach peak condition again?
gpt
Atherosclerotic plaques are made of a lot more than just fat. Immune cells, platlets, the endothelium (inner cellular  lining of blood vessel) all contribute to the plaque build up (physical blockage and chemical signaling). That environment creates a local pocket of inflammation and  screwed up cell signaling which results in those cells taking up excess fat and calcifying it. The calcified fat is the real problem that the body cannot readily deal with, nor do we have good therapeutics for it. While healthy dieting and regular exercise can improve the plaque, it is not 100% reversible. Surgically, we can use angioplasty to widen the plaque to improve blood flow to a tissue - very common treatment for coronary artery disease.