 Hypercholesterolemia, hypercholesterolemia, also called high cholesterol role, is the presence of high levels of cholesterol in the blood. It is a form of hyperlipidemia, high blood lipids, and high perlipoproteinemia elevated levels of lipoproteins in the blood. High levels of non-HEL cholesterol and LDL in the blood may be a consequence of an unhealthy diet, obesity, inherited genetic diseases such as LDL receptor mutations in familial hypercholesterolemia or the presence of other diseases such as type 2 diabetes and an underactive thyroid. Cholesterolemia role is one of three major classes of lipids which all animal cells use to construct their membranes and is thus manufactured by all animal cells. Plant cells do not manufacture cholesterol. It is also the precursor of the steroid hormones and bile acids. Since cholesterol is insoluble in water, it is transported in the blood plasma within protein particles lipoproteins. Lipoproteins are classified by their density, very low density lipoprotein DELDL intermediate density lipoprotein IDL low density lipoprotein LDL and high density lipoprotein HVL. All the lipoproteins carry cholesterol, but elevated levels of the lipoproteins other than HVL termed non-HVL cholesterol role particularly LDL cholesterol role, are associated with an increased risk of atherosclerosis and coronary heart disease. In contrast, higher levels of HVL cholesterol role are protective. Avoiding trans fats and replacing saturated fats in adult diets with polyunsaturated fats are recommended dietary measures to reduce total blood cholesterol and LDL in adults. In people with very high cholesterol EG, familial hypercholesterolemia diet is often not sufficient to achieve the desired lowering of LDL, and lipid lowering medications are usually required. If necessary, other treatments such as LDL atherosclerosis or even surgery for particularly severe subtypes with familial hypercholesterolemia are performed. About 34 million adults in the United States have high blood cholesterol role.