Myths and truth about cholesterol
Section 1: What is cholesterol? Fundamentals and biochemistry
Cholesterol is a waxy substance vital for the functioning of the body. It belongs to the class of lipids, that is, fats, and is synthesized mainly in the liver, although a small amount comes with food. Cholesterol plays a key role in the formation of cell membranes, providing their structure and permeability. Without cholesterol, our cells could not maintain their shape and fulfill their functions.
In addition to the structural role, cholesterol is the predecessor of many important molecules, including:
- Bile acids: It is necessary for digestion and absorption of fats in the intestines. The liver uses cholesterol for the production of bile acids that emulsate fats, facilitating their splitting with enzymes.
- Steroid hormones: Include cortisol, aldosterone, estrogen, progesterone and testosterone. These hormones regulate many physiological processes, from metabolism and immune response to sexual function and development. Cholesterol serves as the basis for their synthesis.
- Vitamin D: It is necessary for the absorption of calcium and phosphorus, maintaining bone health and immune system. Cholesterol is converted into the skin under the influence of sunlight into previtamin D3, which then turns into active vitamin D.
Blood cholesterol transport: lipoproteins
Cholesterol is insoluble in water, so it cannot freely move around the bloodstream. For its transportation, the body uses lipoproteins – spherical particles consisting of lipids (fats) and proteins. There are several types of lipoproteins, the most significant of which:
- Lipoproteins of low density (LDL, LDL): Often called “poor” cholesterol. LDLs deliver cholesterol from the liver to the cells of the body. When the LDL level in the blood is too high, cholesterol can accumulate on the walls of the arteries, forming atherosclerotic plaques.
- High density lipoproteins (HDL, HDL): Often called “good” cholesterol. LDP is collected an excess of cholesterol from cells and arteries and transport it back to the liver for recycling or re -use. A high level of HDL is considered a protective factor against cardiovascular diseases.
- Lipoproteins of very low density (LOPP, VLDL): Basically contain triglycerides, another type of fat. LOPP is tolerate triglycerides from the liver to the cells. After the removal of triglycerides, the LOPPs turn into LDL.
In addition to these main types, there are intermediate lipoproteins, such as intermediate density lipoproteins (LPP, IDL).
Cholesterol level regulation:
The level of cholesterol in the blood is regulated by the complex interaction between the synthesis in the liver, admission to food and excretion. The liver plays a key role in this process, regulating the rate of cholesterol synthesis depending on the needs of the body. When the blood cholesterol is high, the liver reduces its synthesis. When the level of cholesterol is low, the liver increases its synthesis.
Food also affects cholesterol levels. Saturated fats and trans fats contained in some foods can increase the level of LDL cholesterol. Dietary fibers can help reduce cholesterol, connecting it in the intestines and preventing it from absorption.
Genetic factors also play a role in regulating cholesterol levels. Some people are genetically predisposed to a higher or low cholesterol level.
Section 2: “good” and “bad” cholesterol: debunking myths
The terms “good” and “bad” cholesterol, although widespread, are a simplification of a complex picture. In fact, cholesterol is a single substance. “Good” and “bad” it is made by lipoproteins that carry it. It is important to understand that LDL and HDL are not cholesterol, but transport particles containing cholesterol, triglycerides, proteins and other substances.
Myth 1: A high level of total cholesterol is always dangerous.
True: total cholesterol is the amount of LDL, HDL and cholesterol contained in the LOPP. A high level of total cholesterol does not always indicate a problem. For example, a high level of total cholesterol can be due to a high level of HDL, which is a protective factor. It is important to evaluate the level of LDL, HDL and triglycerides, as well as the ratio of LDL/HDL for a more accurate assessment of the risk of cardiovascular diseases.
Myth 2: LDL is always a “bad” cholesterol, and it must be reduced as much as possible.
True: LDL is necessary for the delivery of cholesterol to the cells of the body. The problem occurs when the LDL level is too high, or when LDL particles become oxidized or modified. Oxidized LDLs are more prone to accumulate on the walls of arteries and the formation of atherosclerotic plaques. The desire for an excessively low level of LDL can be unjustified and even harmful. It is important to maintain the optimal level of LDL, taking into account individual risk factors.
Myth 3: HDL is always a “good” cholesterol, and the higher the better.
True: a high level of HDLs, as a rule, is a protective factor against cardiovascular diseases. LDLs remove excess cholesterol from arteries and transport it back to the liver. However, studies show that an excessively high level of HDL (for example, above 90 mg/DL) can be associated with an increased risk of cardiovascular diseases, although this is less common. Moreover, some genetic mutations, leading to a very high level of HDL, are not always associated with a protective effect. It is important to evaluate not only the level of HDL, but also its functionality, that is, its ability to remove cholesterol from cells.
Myth 4: Cholesterol in food directly affects blood cholesterol.
True: most people can consume moderate amount of cholesterol in food without significant effect on blood cholesterol. The liver regulates cholesterol synthesis depending on its admission to food. When we consume more cholesterol, the liver reduces its synthesis, and vice versa. However, in some people, especially in those who are genetically predisposed, cholesterol in food can have a more pronounced effect on blood cholesterol. A more important factor affecting cholesterol is the consumption of saturated and trans fats that stimulate the synthesis of cholesterol in the liver.
Myth 5: Only older people should worry about cholesterol.
True: atherosclerosis, the process of accumulation of cholesterol in the arteries, can begin at a young age. Therefore, it is important to monitor cholesterol from an early age and take measures to maintain it in a healthy range. This is especially true for people with the family history of cardiovascular diseases, obesity, diabetes or other risk factors.
Myth 6: If I have a normal level of cholesterol, I do not need to worry about the health of the heart.
True: normal cholesterol does not guarantee the lack of a risk of cardiovascular disease. Other risk factors, such as high blood pressure, smoking, diabetes, obesity, sitting lifestyle and stress, also play an important role. It is important to consider all risk factors and take comprehensive measures to maintain heart health.
Myth 7: Statins are the only solution for a high level of cholesterol.
True: statins are effective drugs to reduce cholesterol LDL and reduce the risk of cardiovascular diseases. However, they are not the only solution. Change in lifestyle, such as healthy nutrition, regular physical exercises, rejection of smoking and stress control, can significantly improve cholesterol and reduce the risk of cardiovascular diseases. In some cases, changes in lifestyle may be sufficient to maintain a healthy level of cholesterol, while in other cases drug treatment may be required.
Section 3: Factors affecting cholesterol: diet, lifestyle and genetics
The level of cholesterol in the blood is determined by the complex interaction of genetic and environmental factors. Understanding these factors helps to develop an individual strategy for maintaining the health of the heart.
Diet:
Diet plays an important role in the regulation of cholesterol levels. The following aspects are especially important:
- Saturated fats: Contained in fatty meat, dairy products, palm and coconut oil. Saturated fats increase the level of LDL cholesterol. It is recommended to limit the consumption of saturated fats up to less than 6% of the total number of calories.
- Transjir’s: Contained in fried products, baking and processed products. Transfiders increase cholesterol LDL and reduce cholesterol HDL. It is recommended to avoid trans fats.
- Cholesterol: Contained in animal products, such as meat, eggs and dairy products. In most people, cholesterol in food has a slight effect on blood cholesterol. However, in some people, especially in those who are genetically predisposed, cholesterol in food can increase the level of LDL cholesterol. It is recommended to consume a moderate amount of cholesterol in food.
- Food fibers: Contained in fruits, vegetables, whole grain products and legumes. Dietary fibers bind cholesterol in the intestines and prevent it from absorption, which reduces cholesterol LDL. It is recommended to consume at least 25-30 grams of dietary fiber per day.
- Paul -Eathed out fats: Contained in vegetable oils, such as soy, sunflower and corn oil, as well as in oily fish, such as salmon and tuna. Paul -saturated fats can reduce cholesterol LDL. Omega-3 fatty acids contained in oily fish have anti-inflammatory properties and can reduce the risk of cardiovascular diseases.
- Mononasized fats: Contained in olive oil, avocados and nuts. Mononasized fats can increase cholesterol HDL and reduce cholesterol.
Life:
Lifestyle also has a significant impact on cholesterol.
- Physical activity: Regular physical exercises increase cholesterol HDL and reduce cholesterol and triglycerides. It is recommended to engage in moderate physical activity of at least 150 minutes a week, or intensive physical activity of at least 75 minutes a week.
- Smoking: Smoking reduces the level of HDL cholesterol and increases the risk of cardiovascular diseases. Refusal of smoking is one of the most important steps to maintain heart health.
- Obesity: Obesity increases the level of LDL cholesterol, triglycerides and reduces the level of LDP cholesterol. Weight reduction can significantly improve cholesterol.
- Stress: Chronic stress can increase the level of LDL cholesterol and triglycerides. Stress management using methods such as meditation, yoga or communication with friends and family, can help reduce cholesterol.
- Alcohol: Moderate drinking of alcohol (no more than one drink per day for women and no more than two drinks per day for men) can increase the level of HDL cholesterol. However, excessive alcohol consumption can increase the level of triglycerides and harm the liver.
Genetics:
Genetic factors play an important role in the regulation of cholesterol levels. Some people are genetically predisposed to a higher or low cholesterol level. Family hypercholesterolemia is a genetic disease that leads to a very high level of cholesterol LDL and increased risk of cardiovascular diseases at a young age. People with a family history of cardiovascular diseases or high cholesterol should consult a doctor and regularly check cholesterol.
The influence of other diseases:
Some diseases can affect cholesterol.
- Diabetes sugar: Diabetes mellitus can increase the level of LDL cholesterol, triglycerides and reduce cholesterol HDL.
- Kidney diseases: Kidney diseases can increase the level of LDL cholesterol and triglycerides.
- Liver diseases: Liver diseases can affect the synthesis of cholesterol and lipoproteins, which can lead to changes in cholesterol.
- Hypothyroidism: Hypothyroidism (reduced thyroid function) can increase cholesterol LDL.
- Cushing’s syndrome: Kushing syndrome (excess cortisol) can increase the level of LDL cholesterol and triglycerides.
Section 4: Diagnostics and monitoring of cholesterol level: when and how to check?
Regular check of cholesterol is an important part of the prevention of cardiovascular diseases. Recommendations for the frequency and age of the start of checking cholesterol vary depending on individual risk factors.
Screening recommendations:
- Adults (20 years and older): The American Cardiological Association (AHA) recommends the first screening of cholesterol at the age of 20, and then repeat it every 4-6 years if the cholesterol level is normal and there are no other risk factors. If you have risk factors, such as a family history of cardiovascular diseases, obesity, diabetes, smoking or high blood pressure, you may need more frequent screening.
- Children and adolescents: AHA recommends screening cholesterol levels in children and adolescents with a family history of cardiovascular diseases or high cholesterol, obesity, diabetes or other risk factors. It is recommended to conduct screening aged 9 to 11 years and repeatedly at the age of 17 to 21 years.
Types of blood tests for cholesterol:
- Lipidogram (full lipid profile): This analysis measures the level of total cholesterol, LDL cholesterol, HDL cholesterol and triglycerides. Lipidogram is usually on an empty stomach (after 9-12 hours of starvation) to get the most accurate results.
- Non-LPVP cholesterol: This indicator is calculated by subtracting HDL cholesterol from total cholesterol. It includes all the cholesterol contained in lipoproteins, which can contribute to the formation of atherosclerotic plaques, including LDL, LOPP and LPP. NPVP cholesterol can be a useful indicator for assessing the risk of cardiovascular diseases, especially in people with a high level of triglycerides.
- Triglycerides: Triglycerides are a different type of fat in the blood. A high level of triglycerides can increase the risk of cardiovascular diseases, especially in combination with high cholesterol LDL and low cholesterol HDL.
Preparation for blood test for cholesterol:
- On an empty stomach: To obtain the most accurate results of the lipidogram, it is necessary to take an analysis of the oncupe. You will need to refrain from food and drink (except water) within 9-12 hours before analysis.
- Medicines: Tell your doctor about all the medicines that you take, including overcomplex drugs and additives. Some drugs can affect cholesterol.
- Alcohol: Avoid drinking alcohol 24 hours before analysis.
- Physical activity: Avoid intensive physical activity 24 hours before analysis.
Interpretation of analysis results:
The results of blood tests for cholesterol must be interpreted in the context of your individual risk factors. Your doctor will determine the target level of cholesterol for you, given your age, gender, family history, the presence of other diseases and lifestyle factors.
General guidelines for cholesterol levels (MG/DL):
| Indicator | Preferably | Close to normal | High |
|---|---|---|---|
| General cholesterol | < 200 | 200-239 | ≥ 240 |
| LDL cholesterol | < 100 | 100-129 | ≥ 160 |
| LDP cholesterol | ≥ 60 | ||
| Triglycerides | < 150 | 150-199 | ≥ 200 |
These values are common guidelines and can vary depending on individual risk factors.
Additional tests:
In some cases, your doctor may prescribe additional tests to assess the risk of cardiovascular diseases, such as:
- Lipoprotein (a) [Lp(a)]: LP (A) is a type of cholesterol LDL, which is genetically determined and associated with an increased risk of cardiovascular disease.
- Aopolipoprotein B (APOB): APOB is a protein contained in LDL, LOPP and LPP. APOB measurement can be a more accurate risk indicator of cardiovascular diseases than the measurement of cholesterol LDL.
- Coronary calcium (CAC): This analysis uses computed tomography to measure the amount of calcium in the arteries of the heart. A high CAC indicator indicates the presence of atherosclerosis and an increased risk of cardiovascular disease.
- Inflammatory markers (for example, highly sensitive C-reactive protein (HS-CRP)): Inflammation plays a role in the development of atherosclerosis. The measurement of inflammatory markers can help evaluate the risk of cardiovascular diseases.
Section 5: Methods of reducing cholesterol levels: change in lifestyle and drug therapy
There are two main approaches to a decrease in cholesterol: a change in lifestyle and drug therapy. The choice of approach depends on the level of cholesterol, the presence of other risk factors and individual preferences.
Life change change:
Change in lifestyle is the first and most important step in reducing cholesterol. Even small changes can have a significant effect on cholesterol and general health.
- Diet: Review your diet to limit the consumption of saturated fats, trans fats and cholesterol, and increase the consumption of dietary fibers, polyunsaturated and mono -saturated fats. Here are a few specific tips:
- Choose low -fat meat, poultry without skin and fish.
- Use low -fat dairy products.
- Limit the use of fried products, baking and processed products.
- Eat more fruits, vegetables, whole grain products and legumes.
- Use olive oil, avocado and nuts instead of butter and other saturated fats.
- Steam food, cook, bake or grill instead of frying in oil.
- Physical activity: Engage in regular physical activity to increase the level of HDL cholesterol and reduce the level of LDL cholesterol and triglycerides. Try to engage in moderate physical activity of at least 150 minutes a week, or intensive physical activity of at least 75 minutes a week. You can choose any kind of physical activity that you like, such as walking, running, swimming, cycling, dancing or sports.
- Weight loss: If you have overweight or obesity, weight loss can significantly improve cholesterol. Set realistic goals to reduce weight (for example, 5-10% of your starting weight) and achieve them gradually.
- Refusal of smoking: Smoking reduces the level of HDL cholesterol and increases the risk of cardiovascular diseases. Refusal of smoking is one of the most important steps to maintain heart health. Contact the doctor or use the programs to refuse smoking to get help and support.
- Stress management: Chronic stress can increase the level of LDL cholesterol and triglycerides. Manage stress using methods such as meditation, yoga, tai-chi, communication with friends and family, or hobbies.
- Moderate alcohol consumption: Moderate drinking of alcohol (no more than one drink per day for women and no more than two drinks per day for men) can increase the level of HDL cholesterol. However, excessive alcohol consumption can increase the level of triglycerides and harm the liver. If you have problems with alcohol, you should refrain from its use.
Drug therapy:
If a change in lifestyle is not enough to achieve the target level of cholesterol, your doctor may prescribe drug therapy. There are several types of drugs that can reduce cholesterol:
- Statin: Statins are the most commonly prescribed type of drug to reduce cholesterol. They block the enzyme in the liver, which is necessary for cholesterol. Statins effectively reduce cholesterol LDL and reduce the risk of cardiovascular diseases. Side effects of statins can include muscle pain, weakness and increase in the level of liver enzymes.
- Cholesterol absorption inhibitors: These drugs block the absorption of cholesterol in the intestines. They can be used as an addition to statins or as an alternative to statins in people who do not tolerate a hundred