Cholesterol is an essential substance for life, it belongs to the group of sterols. Sterols, in turn, belong to lipids. And the large family of lipids also includes fats.
Functions of Cholesterol in the Body
Cholesterol has extremely important tasks and functions in the human body:
- Cholesterol is part of the cell structure
- Cholesterol is jointly responsible for cell tension and also for cell membrane permeability. (This allows the cell to absorb nutrients and release metabolic waste products while preventing contaminants from passing through the cell membrane.)
- It is an important repair molecule for damaged cell walls.
- It is necessary to produce bile acids.
- Involved in the synthesis of steroid hormones such as estrogens, testosterone, and cortisol
Most of the necessary cholesterol, that is, up to 90%, is produced by the body itself. The remaining amount of the total requirement is absorbed through food.
How is cholesterol transported in your body?
Cholesterol requires protein for its transport. Due to its structural similarity to fats, it is not soluble in water. Cholesterol cannot circulate through the blood as easily. Therefore, for its transport, it requires water-soluble carrier proteins, to which it will bind and thus manage to travel in the blood circulation. These proteins that transport cholesterol and other lipid substances are called lipoproteins.
Carrier proteins transport not only cholesterol, but also other water-insoluble substances, such as fatty acids, phospholipids (lipids that contain phosphorus), and fat-soluble vitamins. Lipoproteins are divided into three categories based on their density:
- HDL (High-Density Lipoprotein)
- LDL (Low-Density Lipoprotein)
- VLDL (Very Low-Density Lipoprotein)
The higher their lipid content, the lower their density and the more harmful they are to health.
What Does "Good" Cholesterol Mean and What Does "Bad" Cholesterol Mean?
The daily reference between good and bad cholesterol is just a simple way to understand cholesterol values. In essence, the good cholesterol is HDL cholesterol, it is known that way because it transports excess cholesterol from the tissues and blood vessels back to the liver. There it is partially converted to bile acids or excreted directly as cholesterol with the bile via the feces.
Consequently, HDL can release cholesterol molecules that have already adhered to the vessel walls and transport them to the liver. This can counteract the development of vasoconstriction caused by cholesterol adhering to the blood vessels.
LDL cholesterol, on the other hand, is the evil brother of HDL cholesterol, which is why it is associated with the negative effects of cholesterol on the body. The function of the LDL molecule is to transport cholesterol from the liver to the tissues. With 46% circulating cholesterol, LDL carries the largest amount of cholesterol throughout the body. HDL, on the other hand, is made up of only 18% cholesterol.
If there is more cholesterol in the blood than the cells need, there is a risk that some of that cholesterol will stick to the walls of the arteries. In this way, deposits could form that would lead to the narrowing of the arteries and ultimately contribute to the development of arteriosclerosis.
What is the Role of VLDL Cholesterol?
VLDL cholesterol is mainly used for the transport of triglycerides since almost half of it is triglycerides (fats that are ingested with food, for example). The cholesterol content is only 10%.
During their journey through the body, special enzymes repeatedly break down VLDL triglycerides to be used for energy production. This continues until the VLDL finally becomes LDL.
Measurement of Cholesterol Levels
All types of cholesterol have important tasks to perform in the body. Therefore, they must be present in sufficient quantities. Sufficient means that there should be neither too much nor too little cholesterol in the blood.
Therefore, a cholesterol level is created to check individual values. To do this, the total cholesterol value, the HDL value, and the LDL value in the blood are measured.
The total cholesterol value results essentially from the sum of the cholesterol contained in HDL and LDL. The concentration of cholesterol in the blood is given in mg/dl (milligrams per deciliter) or mmol/l (millimoles per liter).
The concentration of triglycerides in the blood is also determined. The cholesterol content in the VLDL lipoprotein is usually not measured directly but is calculated from the triglyceride level.
The standard values of the level of cholesterol
Standard values and limit values for individual values are specified to be able to analyze cholesterol levels more precisely.
- Normal value up to 200 mg/dl (5.2 mmol/l)
- Limit value up to 240 mg/dl (6.2 mmol/l)
- Normal value up to 130 mg/dl (3.4 mmol/l)
- Limit value is up to 160 mg/dl (4.15 mmol/l)
- Standard value greater than 45 mg/dl (1.2 mmol/l)
- Normal value below 150 mg/dl (1.7 mmol/l)
Values between 150 and 200 mg/dl are considered borderline but are tolerable if the person is in good health. While values above 200 mg/l are considered too high.
The Relationship Between LDL and HDL is Important
However, the results of the measurement of the individual values are not significant enough to assess the risk of developing arteriosclerosis, because the ratio between LDL cholesterol and HDL cholesterol is particularly decisive for the risk calculation.
This relationship results from the ratio of LDL and HDL and must be less than 3.0. Values above 3.0 and 5.0 represent a health risk. If the value is above this, there is a high risk of developing cardiovascular diseases.
Some people have a genetic defect (abnormalities on chromosome 19) that keeps cholesterol (LDL) levels permanently high. In this case, those affected are missing some of the receptors that allow cholesterol to attach and therefore be taken up by the cell in the first place.
The characteristic finding is to find children with extremely high cholesterol levels, this can be accompanied by variations in the color of the iris of the eye, and in yellowish spots that can appear in large joints (xanthomas) and around the eyes.
How to Prevent High Cholesterol Levels
- Regular Exercise
Hardly any other measure can lower high cholesterol levels in such a sustainable and healthy way as regular exercise, especially aerobic activity such as walking, jogging, or cycling, with as little as 45 minutes a day, can make a difference.
- Avoid Cigarette
Smoking affects cholesterol levels and also alters the functioning of blood vessels. When you smoke, the level of HDL is reduced, resulting in an unfavorable LDL-HDL ratio.
- Food is Fundamental
Studies show that cholesterol values can be reduced by more than 30% with dietary changes. The American Heart Association recommends the Mediterranean diet as one of the best alternatives when it comes to reducing cholesterol levels, this means consuming regularly:
- Fruits, salads, vegetables, and whole grains, accompanied by nuts, seeds, and sprouts.
- Proteins of high biological value such as fish
- Healthy fats (help raise HDL cholesterol levels) Avocados, olive oil, and nuts.
And limit the consumption of:
- Sausage, processed foods
- Refined sugars, flours, and fried foods
- Red meats
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- Kruth H. S. (2001). Lipoprotein cholesterol and atherosclerosis. Current molecular medicine, 1(6), 633–653. https://doi.org/10.2174/1566524013363212
- Lee Y, Siddiqui WJ. Niveles de colesterol. [Actualizado el 26 de julio de 2021]. En: StatPearls [Internet]. Treasure Island (FL): Publicación de StatPearls; 2022 ene-. https://www.ncbi.nlm.nih.gov/books/NBK542294/
- Varghese M. J. (2014). Familial hypercholesterolemia: A review. Annals of pediatric cardiology, 7(2), 107–117. https://doi.org/10.4103/0974-2069.132478