Answer:
Arteriosclerosis are plaques that form within the arteries, producing a decrease in arterial lumen. These plaques are usually made up of fatty tissue, calcium, cholesterol, fats found in the blood.
They are not healthy because they reduce the flow of oxygenated blood to the tissues, producing ischemia or cellular necrosis, for example acute myocardial infarction (when it comes to coronary artery obstruction) or vascular brain disease when the aortic artery is clogged.