Definition: Lipoproteins are complex particles consisting of proteins and fats that circulate in the bloodstream. The chief purpose of lipoproteins is to transport fats -- mainly cholesterol and triglycerides.
Fats are insoluble (they do not dissolve in water) so they have to be "packaged" in such a way that they can flow through the bloodstream. Lipoproteins form a container, made of specialized proteins, for transporting fats.
Examples of Lipoproteins
Chylomicrons are lipoproteins that deliver triglycerides from the intestines to the liver, muscle, and adipose (fat) tissue.LDL (low density lipoproteins) carry cholesterol from the liver to tissues in the body.
HDL (high density lipoproteins) carry excess cholesterol from the body's tissues back to the liver.

