A fatty substance produced predominantly by the liver, and necessary for building cell membranes, insulating the CNS, covering fats for blood transport, forming bile acids, oiling the skin and making steroid hormones. Blood cholesterols are not derived from food (digestion breaks them down) but are intentionally synthesised by the liver, in response to seeming need. Elevated cholesterols are the result of certain types of stress or metabolic imbalances, and the liver makes more than the tissues need. Although not a direct cause, high consumption of fats and proteins will convince the liver to kick into a fat/protein or anabolic stance...THEN it may oversecrete cholesterols, perhaps thinking you are putting food away for the winter.