What is cholesterol? Cholesterol is a substance that has been associated with heart and vascular diseases for years and is generally described as harmful. There is a widespread belief in society that animal products such as eggs, butter, and meat raise cholesterol. However, this view does not fully reflect the functions of cholesterol in the body. Cholesterol is involved in many vital processes, from cell structure to hormone production. What matters is the level and form of cholesterol in the body.
Cholesterol is a fat-like substance produced by the liver and found in cell membranes. It can also be obtained from animal foods (such as meat, eggs, dairy products). Because cholesterol is not water-soluble, it is transported in the blood by carrier proteins called lipoproteins. There are two main types of cholesterol:
- LDL (Low-Density Lipoprotein): Bad cholesterol
- HDL (High-Density Lipoprotein): Good cholesterol
Why is Cholesterol Necessary for the Body?
Cholesterol is part of cell membranes and maintains membrane flexibility. It serves as a precursor in vitamin D synthesis. It is necessary for the production of bile acids and the synthesis of steroid hormones such as estrogen and testosterone. It also contributes to the structure of the myelin sheath surrounding nerve cells, which enables nerve conduction. In short, cholesterol is a vital component for the body as long as its balance is not disturbed.
What is LDL Cholesterol and Why is it Harmful?
LDL cholesterol carries cholesterol produced in the liver to cells. This process is normally necessary, but when the LDL level in the blood rises, excess cholesterol begins to accumulate in the vessel walls. This accumulation eventually leads to plaque formation. These plaques:
- Cause narrowing and hardening of the arteries (atherosclerosis)
- Obstruct blood flow, reducing oxygen transport
- Increase the risk of heart attack and stroke
LDL cholesterol is considered “high” if above 130 mg/dL, and “very high” if above 160 mg/dL.
What Does HDL Cholesterol Do?
HDL cholesterol collects excess cholesterol from the arteries and transports it to the liver for elimination from the body. Therefore, HDL works like a “cleaning system” that protects the arteries. HDL cholesterol reduces the risk of heart attack and stroke by preventing plaque formation in the arteries.
High HDL levels have a protective effect against heart and vascular diseases. It is recommended that HDL levels in a healthy adult be above 40 mg/dL. In women, this value is generally higher (50 mg/dL and above).
Cholesterol and Cardiovascular Health
High LDL levels lead to plaque formation in artery walls, bringing serious risks such as heart attack, stroke, and peripheral vascular diseases. HDL helps reverse this process. Therefore, not only total cholesterol but also the ratio of HDL to LDL is important.
Factors Affecting Cholesterol Levels
The following factors are determinant on cholesterol levels:
- Genetic predisposition
- Age and gender
- Inactivity and obesity
- Diet rich in saturated and trans fats
- Smoking
- Insufficient fiber consumption
What to Do for Cholesterol Balance?
The following steps are recommended to keep cholesterol levels within healthy limits:
- Reduce consumption of saturated and trans fats
- Consume fibrous foods (oats, vegetables, fruits, whole grains)
- Exercise at least 150 minutes per week
- Quit smoking
- Use medication with doctor’s recommendation when necessary
- Adopt a Mediterranean-style diet
Cholesterol is not a substance to be completely avoided. It is necessary for the body but should be in the right type and at the right level. While high LDL poses a risk, adequate HDL levels provide a protective effect. It is possible to maintain cholesterol balance with healthy lifestyle habits.
