Blood lipids refer to a group of fatty substances present in blood, mainly including cholesterol and triglycerides. There are generally two forms of cholesterols circulating in the bloodstream: low-density lipoprotein (LDL) and high-density lipoprotein (HDL). Abnormal lipid level in blood is always associated with a number of diseases, such as high blood pressure, coronary arteries, hypothyroidism, type 2 diabetes, obesity, pancreatitis, et al.