Hypercholesterolemia (literally: high blood cholesterol) is the presence of high levels of cholesterol in the blood.It is not a disease but a metabolic derangement that can be secondary to many diseases and can contribute to many forms of disease, most notably cardiovascular disease.It is closely related to the terms “hyperlipidemia” (elevated levels of lipids) and “hyperlipoproteinemia” (elevated levels of lipoproteins).Elevated cholesterol in the blood is due to abnormalities in the levels of lipoproteins, the particles that carry cholesterol in the bloodstream. This may be related to diet, genetic factors (such as LDL receptor mutations in familial hypercholesterolemia) and the presence of other diseases such as diabetesand an underactive thyroid. The type of hypercholesterolemia depends on which type of particle (such as low density lipoprotein) is present in excess.

http://en.wikipedia.org/wiki/High_cholesterol

Robert Rosenson, MD

Such as cholesterol and triglycerides, are fats that are an integral part of cells, and that may dissolve in alcohol, but are insoluble in water. They are thus insoluble in the blood. In order for lipids to be transported in blood, they are packaged as lipoprotein. Lipoproteins have a shell of phospholipids and proteins that allow them to dissolve in blood. The lipids, transported as lipoprotein, are transported to various tissues for energy utilization, lipid deposition, steroid hormone production, and bile acid formation.

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