What is Hypercholesterolaemia?

Reading time: 4 min

Hypercholesterolaemia refers to abnormally high levels of cholesterol in the blood. Cholesterol is a substance that is found naturally in all body cells. While it is present in foods of animal origin, it can also be produced autonomously by human cells. Cholesterol is distributed through the bloodstream, and is necessary for the normal functioning of the organism. However, high levels of cholesterol increase the risk of developing cardiovascular diseases if it accumulates in artery walls. This process is called atherosclerosis. 

Hypercholesterolaemia in first person

Professionals and patients explain how you live with the disease
Hypercholesterolaemia | PortalCLÍNI...
The risk factors associated with high cholesterol are smoking, obesity, diabetes, high blood pressure, a sedentary lifestyle and close relatives who have had a cardiovascular disease, heart attack or stroke.
Hypercholesterolaemia explained in ...
Cholesterol is a silent disease. In other words, you don’t notice any symptoms, until you do. So, it’s better to prevent. And, in general, giving up smoking, giving up drinking, doing everything that everyone says you should do for a healthy life.

What is cholesterol?

Cholesterol is fat-like substance or lipid of the sterol family and the most prevalent sterol in animals. Plant sterols are called phytosterols. Cholesterol circulates throughout the body via the bloodstream. Cholesterol is used as a construction component to give consistency to cell walls, and is also used to produce certain hormones necessary for the normal functioning of our body, among other processes. 

However, hypercholesterolemia, or an increase in the level or amount of cholesterol in the blood, can be harmful. Its build-up can lead to the development of cardiovascular diseases such as heart infarction, stroke or poor blood irrigation of limbs due to atheroma deposited in the arteries.

These cholesterol levels are taken as a reference point for evaluating aspects of cardiovascular health or prompting the need to introduce measures to reduce them. They should not be confused with each patient’s desirable individual target values, which depend on their specific risk factors, age and any other diseases they may have.

Where does cholesterol come from?

The cholesterol that circulates in our body comes, on the one hand, from animal-based foods that we consume. In addition, our cells (mainly those in the liver) independently produce the cholesterol they need.
The liver acts as a cholesterol service station: it serves as a reservoir and functions as both the source and destination of the cholesterol that constantly moves to and from the body’s tissues and arteries. However, cholesterol does not circulate freely in the blood. Since it is a fat, it cannot move through an aqueous medium, just as oil cannot mix with water. Therefore, cholesterol is transported within small spheres called lipoproteins, which allow it to circulate and be distributed throughout the body.

In a normal situation, the body maintains cholesterol levels in a balanced equilibrium between production (both biosynthesised and absorbed from food) and elimination through the digestive tract. When there is little quantity in the feed, internal production increases and elimination is reduced. In other words, the body is well prepared to live with very little cholesterol, but it is not very well prepared to destroy or eliminate it. Therefore, when the body receives too much cholesterol because of an unhealthy diet, it gradually accumulates and deposits in the arteries.

Cholesterol circulating inside LDL lipoproteins (bad cholesterol) filters from the blood into the wall of the arteries. The body interprets these cholesterol deposits as harmful and, in its attempt to eliminate them, it initiates an inflammatory response which subsequently transforms the deposits into atheromatous plaques (cholesterol plaques). These plaques are responsible for cardiovascular diseases.

Types of Hypercholesterolaemia

Hypercholesterolaemia is classified based on its:

  • Origin:
    •  As secondary hypercholesterolaemia. Are produced when it is caused by an underlying disease (e.g. diabetes, obesity, low thyroid hormone levels, certain kidney and liver diseases, amongst others); circumstances (pregnancy); a medication (some acne tablets, contraceptives or cortisone, for example); or a poor diet (high in fats, sugar, alcohol). All these situations are primarily causes high cholesterol levels.
    • As primary hypercholesterolaemia. When it is essentially due to an inherited defect in the genes which control the body’s cholesterol levels. Some examples are familial hypercholesterolaemia, familial combined hyperlipidaemia or polygenic hypercholesterolaemia. In many cases people with primary hypercholesterolaemia also have secondary causes that contribute to increased cholesterol levels and make it even harder to control their condition.
  • Presentation. Situations may arise in which only cholesterol levels are elevated (pure hypercholesterolemia), while in other cases, these high cholesterol levels are also associated with an increase in triglycerides (hyperlipidemia or mixed dyslipidemia), or with low levels of HDL lipoproteins —the so-called “good” cholesterol.

How many people are affected by Hypercholesterolaemia?

It is difficult to determine the prevalence of cholesterol-related diseases. Elevated cholesterol levels vary according to age and sex, as well as racial or ethnic background, and even cultural, nutritional, or healthcare factors.
In general terms, considering the “ideal” cholesterol levels, it is estimated that 1 in 2 people do not have them. About 5–20% of the population have cholesterol levels above 240–250 mg/dl. One in every 250 people has familial hypercholesterolemia, and more than 50–80% of them are unaware of it. Additionally, approximately 1–5% of the population may have familial combined hyperlipidemia.

Substantiated information by:

Antonio J. Amor Fernandez
Daniel Zambón Rados
Emilio Ortega Martinez de Victoria
Gemma Yago Esteban
Manel Mateu Salat
Violeta Moize Arcone

Published: 2 October 2018
Updated: 10 October 2025

The donations that can be done through this webpage are exclusively for the benefit of Hospital Clínic of Barcelona through Fundació Clínic per a la Recerca Biomèdica and not for BBVA Foundation, entity that collaborates with the project of PortalClínic.

Subscribe

Receive the latest updates related to this content.

Thank you for subscribing!

If this is the first time you subscribe you will receive a confirmation email, check your inbox

An error occurred and we were unable to send your data, please try again later.