category: nutrition science: nutrients

Cholesterol, LDL, HDL, de.: Cholesterin

Cholesterol (gr.: cholé = bile and sterós = solid) is a sterol, a substance similar to fat, or more precise a component of fat that is found mainly in foods of animal origin but also some vegetable oils. Cholesterol is synthesized in the body for the largest part but some of it is of dietary origin. Production within the body takes place in the fat and carbohydrate metabolism, mainly in the liver and intestinal mucosa. The cholesterol synthesis (production) of the body adjusts depending on the dietary intake of cholesterol. This process differs individually though and has a maximum level. The maximum intake of cholesterol is usually considerably below 1000 mg per day.

Cholesterol is part of all cell membranes in animal tissue and an essential precursor for vitamin D and various hormones.

Cholesterol is only negative for people with high cholesterol concentrations in the blood and vascular walls. Elderly people or those with heart and vascular diseases should therefore minimize their cholesterol intake. In general a dietary intake of 300 mg per day is recommended.

All animal derived foods contain cholesterol but foods especially high in cholesterol are: eggs with 396 mg (*), butter with 240 mg (*), oysters with 260 mg (*), beef liver with 354 mg (*), pork liver with 393 mg (*) and chicken liver with 555 mg (*). Detrimental to health are only those foods that stimulate the metabolism to produce even more cholesterol. Those foods usually contain large amounts of saturated fatty acids. The intake of these foods should be reduced to an absolute minimum, since the production of cholesterol within the body may be much more than the intake of cholesterol through the food.

* The stated amounts refer to 100 g of the edible part of the food.

LDL and HDL

Cholesterol is not soluble in water or blood. It is transported through the body within certain proteins. Protein-cholesterol connections belong to the lipoproteins. LDL or Low Density Lipoprotein is such a lipoprotein. Where the concentration of LDL within the blood is too high, it may cling to the vascular walls and form plaques. LDL is thus associated with atherosclerosis and in consequence with heart attacks. HDL or High Density Lipoprotein is also a lipoprotein. In contrast to LDL it seems to protect the vascular walls of plaques. A high level of HDL therefore seems to prevent atherosclerosis.