Cholesterol (lipoproteins, also called lipids) and triglyceride are fat-soluble substances needed for several body functions, such as making healthy cell membranes and for lining of nerves in the brain.  High levels of “bad” cholesterol (such as LDL and VLDL) and/or triglycerides can lead to increased risk for heart disease or strokes. High levels of “good” cholesterol (HDL) can be protective against heart disease and stroke.