What is Cholesterol?

 In This Article, What is Cholesterol? Cholesterol is a kind of blood fat from the group of sterols and a vital component of our cell membranes. Cholesterol is also needed to make bile acids, sex hormones, and vitamin D.

Cholesterol is found in almost all tissues of our body and is an important building block for numerous metabolic processes. To ensure that this vital substance is present in sufficient quantity, our body produces cholesterol itself. Normally about 60% of the required cholesterol is produced in the body, especially in the liver. The remainder is taken up via the food (animal fats).

Like fat, cholesterol is not soluble in water. But to get it through the blood from the liver to the tissues, cholesterol needs specialized "fat droplets" - the so-called lipoproteins - made up of cholesterol and other fats ("lipids") and protein molecules ("proteins"),

Lipoproteins are Classified According to Their Density into Three Categories:

• VLDL (very low-density lipoproteins)

• LDL (low-density lipoproteins)

• HDL (high-density lipoproteins)

While high LDL concentrations can lead to vascular calcification (also called arteriosclerosis or atherosclerosis), high HDL concentrations have a protective effect on the vessel walls. Therefore, one often speaks of "bad" and "good" cholesterol.

Why Does the Body Need Cholesterol?

• Cholesterol has vital functions and functions in our body:

• Cholesterol is a necessary component of body cells

• Cholesterol is an essential repair molecule of damaged cell walls

• Cholesterol is needed to produce bile acids and excreted as such

• Cholesterol is important for producing certain hormones, e.g. Estrogen or testosterone

• Cholesterol is the starting material needed for the production of vitamin D.

In Which Cases is the Cholesterol Determined?

As cholesterol contributes to the development of cardiovascular diseases such as heart attack and stroke via atherosclerosis, cholesterol is routinely determined in the case of large blood counts and as part of the annual check-up. In the process, the cholesterol value in the blood serum is measured. Importantly, there should not be too much cholesterol in the blood and the "good" HDL cholesterol is not low.

• In addition, cholesterol should be regularly determined in humans with:

• Cardiovascular diseases (high blood pressure, thrombosis, PAD, heart attack, stroke)

• Obesity

• Cardiovascular diseases or lipid metabolism disorders in the family

Which Cholesterol Levels Should be sought?

In addition to the (total) cholesterol level in the blood serum, the LDL and HDL cholesterol, as well as the so-called triglycerides, should be measured to obtain a meaningful picture. The level of cholesterol depends on age, gender and other individual risk factors such as diet or cardiovascular disease. The following target values apply:

                               Source: Austrian Lipid Consensus (2016)

RISK CATEGORY	TARGET FOR  LDL CHOLESTEROL LEVEL	TARGET FOR TOTAL CHOLESTEROL WITHOUT HDL CHOLESTEROL
VERY HIGH	<70 Mg/Dl	<100 Mg/Dl
HIGH	<1OOMg/Dl	<130Mg/Dl
MODERATE	<130Mg/Dl	<160Mg/Dl
LOW	<160Mg/Dl	<190Mg/Dl

* Total cholesterol minus HDL cholesterol should be used if triglycerides exceed 200 mg/dl.

Who Should Pay Particular Attention to its Cholesterol Levels?

High levels of cholesterol are especially harmful to people at very high risk for a cardiovascular event (such as a heart attack):

• Acute coronary syndrome (acute myocardial infarction, unstable angina pectoris)

• Coronary heart disease, e.g. for stable angina pectoris, previous myocardial infarction, stent insertion

• After stroke and atherosclerosis of the carotid artery

• In arterial circulatory disorders in the legs

• Type 2 diabetes and advanced type 1 diabetes

Progressive, recurrent or reoccurring coronary heart disease despite LDL cholesterol below 100 mg/dl.

High-risk patients include, but are not limited to, those with:

• Familial hypercholesterolemia (inherited elevated LDL cholesterol levels)

• Diabetes mellitus type 1 if over 40 years

• Severe other risk factors for cardiovascular disease (e.g., high blood pressure)

• Most people have a moderate risk with two of the so-called classic risk factors; these include:

• Age: men> 45 years, women> 55 years

Positive family history of the early-onset cardiovascular disease (first-degree male infants less than 55 Years old, first-degree female infants less than 65 years old)

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• High blood pressure (hypertension): systolic blood pressure above 135 mmHg and diastolic blood pressure above 85 mmHg or taking antihypertensive medication

• Low HDL (men under 40 mg/dl, women under 50 mg/dl); with HDL-Cholesterol above 60 mg/dl, however, a risk factor can be deducted

• People with a Maximum of One Classic Risk Factor have a Low Risk.

What are Possible Causes of High Cholesterol (hypercholesterolemia)?

Frequent consumption of red meat, sausages and saturated fat, trans-fatty acids

• Genetic preload

• Obesity

Nephrotic syndrome (complex of symptoms of increased protein in the urine, elevated blood lipid levels and peripheral edema)

• Hypothyroidism

• Biliary stasis

• Diabetes mellitus

• Pregnancy

• Taking certain medications, i.a. Cortisone preparations and Progestins

What are possible causes of low cholesterol (hypocholesterolemia)?

• Malnutrition

• Cirrhosis

• Rare genetic lipid metabolism diseases

• Manganese deficiency

• Hyperthyroidism (hyperthyroidism)