While cholesterol plays an important role in the human body as a natural substance, it also poses risks to health. For example, various diseases are associated with elevated cholesterol levels. For more information, read the article: Elevated cholesterol (hypercholesterolemia).
What is cholesterol?
A blood test of cholesterol levels is used by doctors to further diagnose various diseases. Cholesterol is an important molecule and lipid (fat) found primarily in animal cells. The human body absorbs needed cholesterol with food, but also produces it itself. The body’s own production of cholesterol takes place in the liver and intestines. Since cholesterol is poorly soluble in water, it requires transport agents in the bloodstream of the human body. These transport agents are certain proteins, also known as lipoproteins. The lipoproteins LDL (low density lipoprotein cholesterol) and HDL (high density lipoprotein cholesterol) are primarily responsible for the transport of cholesterol. The cholesterol level in a person’s blood can be determined with the help of a blood analysis. In this process, the HDL cholesterol level is also colloquially referred to as the ‘good cholesterol’, while the LDL cholesterol is also called ‘bad cholesterol’.
Meaning and function
Cholesterol performs important functions in the human body. For example, cholesterol is a component of cell walls. Cholesterol is needed to build and maintain cell membranes. Furthermore, cholesterol serves to produce substances such as bile acid (which aids digestion, for example), is a basis for the formation of so-called steroid hormones (which include the sex hormones) and for the formation of fat-soluble vitamins such as vitamin D (which is important for the mineralization of bones, for example), vitamin A and vitamin E. Science assumes that cholesterol has antioxidant properties. This means that it can counteract unwanted oxidation of the body’s own substances, which otherwise may promote the development of diseases and promote aging processes. According to studies, cholesterol has an important role in the body’s immune system; here, cholesterol is said to promote protective functions against cancer, among other things. A high percentage of cholesterol is found in breast milk. This is probably due to the fact that cholesterol plays an important role in the development of the brain and nervous system. Studies have shown links between low cholesterol and various problems. For example, a low level of cholesterol in expectant mothers has been shown to be a risk factor for low birth weight of the newborn child. Also, in children and adolescents, low cholesterol levels were shown to be associated with a high number of school expulsions. Finally, low cholesterol was also identified as a possible risk factor for the development of depression.
Hazards, disorders, risks, and diseases
In addition to its important functions in the human body, cholesterol can also contribute to various diseases. In particular, an elevated level of so-called LDL cholesterol is held partly responsible in medicine, for example, for the development of arteriosclerosis and so-called coronary heart disease (also abbreviated as CHD). Arteriosclerosis is a hardening of the arteries that is promoted, among other things, by the deposition of cholesterol on the arterial walls. This restricts a regulated blood flow and can thus lead to increased blood pressure and coronary heart disease, in which the heart muscle is not supplied with sufficient blood. In addition, the hardening of the arteries promoted by cholesterol is a risk factor for suffering a heart attack. Stroke is also one of the diseases whose risk can be increased by cholesterol. This is the case, for example, if the carotid artery is narrowed. Possible consequences of a stroke include speech and movement disorders. Cholesterol is also a component of gallstones. Although the cholesterol content in bile is comparatively high anyway, if the body is supplied with large amounts of cholesterol, the bile can change.The background to this is that cholesterol is very poorly soluble in bile and, as a result, so-called cholesterol stones form. While gallstones have different structures, cholesterol gallstones occur most frequently. Possible consequences of gallstones include biliary colic, which is cramping pain in the upper abdomen.