Hyperlipidemia, also called hyperlipoproteinemia, is a condition that occurs when an elevated level of fats or lipids consisting of cholesterol, cholesterol compounds, phospholipids and triglycerides enter the bloodstream. Inside the bloodstream these fatty substances attach to proteins, travel through the body (liquid form). When the fats and proteins combine in the blood they form large molecules called lipoproteins. This leads to arteriosclerotic heart disease. (heart attack and stroke)