Cholesterol: What causes high cholesterol?

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Cholesterol is an essential substance for the body. Dietary factors and some health conditions can lead to high cholesterol, which is a risk factor for several conditions.

Cholesterol is present in every cell of the body and has important natural functions when it comes to digesting foods, producing hormones, and generating vitamin D. The body produces it, but people also consume it in food. It is waxy and fat-like in appearance.

There are two types of cholesterol:

• low-density lipoproteins (LDL), or “bad” cholesterol
• high-density lipoproteins (HDL), or “good” cholesterol

In this article, we will explain the role of cholesterol. We will also discuss the causes of high cholesterol, and its symptoms, treatment, and prevention.

Fast facts on cholesterol:

• Cholesterol is an essential substance that the body produces but which people also consume in foods.
• Risk factors for high cholesterol include family history and the modifiable lifestyle choices of diet and exercise.
• Having high cholesterol does not usually produce any symptoms.
• If lifestyle changes are unsuccessful or cholesterol levels are very high, a doctor may prescribe a lipid-lowering drug, such as a statin.

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Cholesterol is an oil-based substance. It does not mix with the blood, which is water-based.

It travels around the body in lipoproteins.

Two types of lipoprotein carry the parcels of cholesterol:

• Low-density lipoprotein (LDL): Cholesterol that travels in this way is unhealthful or “bad” cholesterol.
• High-density lipoprotein (HDL): Cholesterol that is present in HDL is known as “good” cholesterol.

Cholesterol has four primary functions, without which we could not survive.

These are:

• contributing to the structure of cell walls
• making up digestive bile acids in the intestine
• allowing the body to produce vitamin D
• enabling the body to make certain hormones

High cholesterol is a significant risk factor for coronary heart disease and a cause of heart attacks.

A build-up of cholesterol is part of the process that narrows arteries, called atherosclerosis. In atherosclerosis, plaques form and cause restriction of blood flow.

Reducing the intake of fat in the diet helps to manage cholesterol levels. In particular, it is helpful to limit foods that contain:

• Cholesterol: This is present in animal foods, meat, and cheese.
• Saturated fat: This occurs in some meats, dairy products, chocolate, baked goods, deep-fried, and processed foods.
• Trans fats: This occurs in some fried and processed foods.

Excess weight or obesity can also lead to higher blood LDL levels. Genetic factors can contribute to high cholesterol. People with the inherited condition familial hypercholesterolemia have very high LDL levels.

Other conditions that can lead to high cholesterol levels, include:

• diabetes
• liver or kidney disease
• polycystic ovary syndrome
• pregnancy and other conditions that increase levels of female hormones
• underactive thyroid gland
• drugs that increase LDL cholesterol and decrease HDL cholesterol, such as progestins, anabolic steroids, and corticosteroids

A person with high cholesterol levels often has no signs or symptoms, but routine screening and regular blood tests can help detect high levels.

A person who does not undergo testing may have a heart attack without warning, because they did not know that they had high cholesterol levels. Regular tests can help to reduce this risk.

A report from Harvard Health has identified 11 cholesterol-lowering foods that actively decrease cholesterol levels:

• oats
• barley and whole grains
• beans
• eggplant and okra
• nuts
• vegetable oil (canola, sunflower)
• fruits (mainly apples, grapes, strawberries, and citrus)
• soy and soy-based foods
• fatty fish (particularly salmon, tuna, and sardines)
• foods rich in fiber

Adding these to a balanced diet can help keep cholesterol in check.

The same report also lists foods that are bad for cholesterol levels. These include:

• red meat
• full-fat dairy
• margarine
• hydrogenated oils
• baked goods

Various low cholesterol recipe books are available to purchase online.

In adults, total cholesterol levels less than 200 milligrams per deciliter (mg/dL) are considered healthy.

• A reading between 200 and 239 mg/dL is borderline high.
• A reading of 240 mg/dL and above is considered high.

LDL cholesterol levels should be less than 100 mg/dL.

• 100–129 mg/dL is acceptable for people with no health problems but may be a concern for anyone with heart disease or heart disease risk factors.
• 130—159 mg/dL is borderline high.
• 160–189 mg/dL is high.
• 190 mg/dL or higher is considered very high.

HDL levels should be kept higher. The optimal reading for HDL levels is of 60 mg/dL or higher.

• A reading of less than 40 mg/dL can be a major risk factor for heart disease.
• A reading from 41 mg/dL to 59 mg/dL is borderline low.

People who wish to reduce their cholesterol levels or maintain a suitable level can make four major lifestyle decisions.

• eat a heart-healthy diet
• regularly exercise
• avoid smoking
• achieve and maintain a healthy weight

These actions will reduce the risk of coronary heart disease and heart attack.

Since 2013, guidelines on reducing or preventing high cholesterol have focused on addressing lifestyle risks, even at a young age.

Since 2018, new guidelines published in the Journal of the American College of Cardiology also urged doctors also to discuss with individuals the following factors that may increase a person’s risk:

• family history and ethnicity
• certain health conditions that increase the risk of high cholesterol, such as chronic kidney disease or chronic inflammatory conditions

Taking these factors into consideration will lead to a more personalized approach to the treatment and prevention of high cholesterol levels.

There are a number of ways to treat high cholesterol; these include:

Lipid-lowering therapy

For a person with high cholesterol levels, drug treatment will depend on their cholesterol level and other risk factors.

Recommendatoins usually start with diet and exercise, but people with a higher risk of a heart attack may need to use statins or other medications.

Statins are the leading group of cholesterol-lowering drugs. The statins available on prescription in the United States include:

• atorvastatin (brand named Lipitor)
• fluvastatin (Lescol)
• lovastatin (Mevacor, Altoprev)
• pravastatin (Pravachol)
• rosuvastatin calcium (Crestor)
• simvastatin (Zocor)

Apart from statins, a doctor may prescribe:

• selective cholesterol absorption inhibitors
• resins
• fibrates
• niacin

In 2017, researchers noted that a new drug, ezetimibe, can significantly reduce the risk of a major cardiovascular event in people with a high risk of such events. Etezimibe reduces lipid levels by limiting the absorption of cholesterol in the intestine.

The authors of the updated also mentioned another new type of drug: pro-protein convertase subtilisin/kexin 9 (PCSK9) inhibitors. There is evidence that these drugs are effective at reducing cholesterol levels, especially when a person uses them with ezetimibe.

In 2018, new guidelines recommended a stepped approach, depending on how high an individual’s risk is.

If a person has already had a cardiovascular event, such as a heart attack, a doctor may recommend using ezetimibe as well as a statin. For those at very high risk, the guidelines also recommend adding a PCSK9 inhibitor.

However, the guidelines also note that PCSK9 inhibitors are expensive, and insurance companies may not cover their cost. For this reason, this option is likely to be only for those with a very high risk.

Statin safety

The use of statins has caused some debate because, like all drugs, they can have side effects.

These include:

• statin-induced myopathy (a muscle tissue disease)
• fatigue
• a slightly greater risk of diabetes and diabetes complications, though this is hotly debated

A person should not stop taking a statin without speaking to a doctor, as they may increase their risk of cardiovascular problems.

A doctor might recommend:

• switching to a different medication
• increasing efforts to reduce cholesterol through lifestyle changes

In the past, people have aimed to reduce cholesterol to a target level, for instance, below 100 mg/ dL, but this is no longer the case.

Randomized, controlled clinical trials have not produced enough evidence to support treatment to a specific target.

However, some physicians may still use targets to help guide therapy.

10-year risk of a heart attack

Cholesterol levels play a major part in an individual’s risk of having a heart attack within the next 10 years.

The National Heart, Lung, and Blood Institute provide an online calculator of cardiovascular risk.

Using research evidence, it weighs the risk according to these factors:

• age
• sex
• cholesterol levels
• smoking status
• blood pressure

Guidelines published in 2018 consider this calculator and essential tool for assessing cholesterol levels and their risk.

Symptoms, Causes, Levels, and More

Causes of high cholesterol include diet, smoking, and genetics. High cholesterol rarely causes symptoms, so it’s important to have routine cholesterol screenings if you’re at risk.

High cholesterol is a pretty common issue in the U.S. In fact, according to the Centers for Disease Control and Prevention (CDC), nearly 94 million U.S. adults ages 20 or older have what could be considered borderline high cholesterol.

However, because this condition can often present without any real symptoms, you may not even know you have it until you visit your doctor.

If you’re wondering what causes high cholesterol, what to do if you’ve been diagnosed with it, and if there are ways to reverse it (hint: there are), read on for all the answers.

Cholesterol is a type of lipid. It’s a waxy, fat-like substance that your liver produces naturally. It’s vital for the formation of cell membranes, certain hormones, and vitamin D.

Cholesterol doesn’t dissolve in water, so it can’t travel through your blood on its own. To help transport cholesterol, your liver produces lipoproteins.

Lipoproteins are particles made from fat and protein. They carry cholesterol and triglycerides, another type of lipid, through your bloodstream. The two major forms of lipoprotein are low-density lipoprotein (LDL) and high-density lipoprotein (HDL).

LDL cholesterol is any cholesterol carried by low-density lipoproteins. If your blood contains too much LDL cholesterol, you may be diagnosed with high cholesterol. Without treatment, high cholesterol may lead to many health issues, including heart attack and stroke.

High cholesterol rarely causes symptoms in the beginning. That’s why it’s important to get your cholesterol levels checked on a regular basis.

In most cases, high cholesterol is a “silent” condition. It typically doesn’t cause any symptoms. Many people don’t even realize they have high cholesterol until they develop serious complications, such as a heart attack or stroke.

That’s why routine cholesterol screening is important. If you’re 20 years or older, ask your doctor if you should have routine cholesterol screening. Learn how this screening could potentially save your life.

Eating too many foods that are high in cholesterol, saturated fats, and trans fats may increase your risk of developing high cholesterol. Living with obesity can also increase your risk. Other lifestyle factors that can contribute to high cholesterol include inactivity and smoking.

Your genetics can also affect your chances of developing high cholesterol. Genes are passed down from parents to children. Certain genes instruct your body on how to process cholesterol and fats. If your parents have high cholesterol, you may be at a greater risk of having it too.

In rare cases, high cholesterol is caused by familial hypercholesterolemia. This genetic disorder prevents your body from removing LDL. According to the National Human Genome Research Institute, most adults with this condition have total cholesterol levels above 300 milligrams per deciliter and LDL levels above 200 milligrams per deciliter.

Other health conditions, such as diabetes and hypothyroidism, may also increase your risk of developing high cholesterol and related complications.

LDL cholesterol is often called “bad cholesterol.” It carries cholesterol to your arteries. If your levels of LDL cholesterol are too high, it can build up on the walls of your arteries.

This buildup is also known as cholesterol plaque. This plaque can narrow your arteries, limit your blood flow, and raise your risk of blood clots. If a blood clot blocks an artery in your heart or brain, it can cause a heart attack or stroke.

HDL cholesterol is sometimes called “good cholesterol.” It helps return LDL cholesterol to your liver to be removed from your body. This helps prevent cholesterol plaque from building up in your arteries.

When you have healthy levels of HDL cholesterol, it can help lower your risk of blood clots, heart disease, and stroke.

Triglycerides are another type of lipid. They’re different from cholesterol. While your body uses cholesterol to build cells and certain hormones, it uses triglycerides as a source of energy.

When you eat more calories than your body can use right away, it converts those calories into triglycerides. It stores triglycerides in your fat cells. It also uses lipoproteins to circulate triglycerides through your bloodstream.

If you regularly eat more calories than your body can use, your triglyceride levels may become too high. This can raise your risk of several health problems, including heart disease and stroke.

Your doctor can use a simple blood test to measure your triglyceride level, as well as your cholesterol levels.

If you’re 20 years or older, the American Heart Association recommends getting your cholesterol levels checked at least once every 4 to 6 years. If you have a history of high cholesterol or other risk factors for cardiovascular disease, your doctor may encourage you to get your cholesterol levels tested more often.

Your doctor can use a lipid panel to measure your total cholesterol level, as well your LDL cholesterol, HDL cholesterol, and triglyceride levels. Your total cholesterol level is the overall amount of cholesterol in your blood. It includes LDL and HDL cholesterol.

If your levels of total cholesterol or LDL cholesterol are too high, your doctor may diagnose you with high cholesterol. High cholesterol can be dangerous when your LDL levels are too high and your HDL levels are too low.

If you need help finding a primary care doctor, then check out our FindCare tool here.

Cholesterol levels chart

Being diagnosed with high cholesterol doesn’t automatically mean you will be put on medication. If your doctor does prescribe you medication, different factors may influence the type of medication they recommend.

With this in mind, most physicians use generalized measurements to decide on treatment plans. They may categorize these measurements as desirable, borderline high, or high cholesterol.

According to the National Library of Medicine, the total cholesterol of most adults can be categorized as:

The National Library of Medicine also provides optimal to high categories of LDL (“bad”) cholesterol levels:

Again, these measurements are general. You and your doctor will consider other personal factors before deciding on a treatment plan.

Your body needs some cholesterol to function properly, including some LDL. But if your LDL levels are too high, it can raise your risk of serious health problems.

In 2018, the American College of Cardiologists and the American Heart Association updated their recommendations for the treatment of high cholesterol.

Under the new guidelines, in addition to your cholesterol levels, treatment recommendations analyze other risk factors for heart disease, such as family history and other health issues. The guidelines use all these factors to consider a person’s overall chance of developing complications during the next 10 years.

You may be at a higher risk of developing high cholesterol if you:

• are living with obesity
• consume a lot of saturated and trans fats, like those found in fast food
• have limited physical activity
• smoke tobacco products
• have a family history of high cholesterol
• have diabetes, kidney disease, or hypothyroidism

People of all ages, genders, and ethnicities can have high cholesterol.

Without treatment, high cholesterol can cause plaque to build up in your arteries. Over time, this plaque can narrow your arteries. This condition is known as atherosclerosis.

Atherosclerosis is a serious condition. It can limit the flow of blood through your arteries. It also raises your risk of developing dangerous blood clots.

Atherosclerosis can result in many life threatening complications, such as:

• stroke
• heart attack
• angina, or chest pain
• high blood pressure
• peripheral vascular disease
• chronic kidney disease

High cholesterol can also create a bile imbalance, raising your risk of gallstones. See the other ways that high cholesterol can impact your body.

If you have high cholesterol, your doctor may recommend lifestyle changes to help lower it. For instance, they may recommend changes to your diet, exercise habits, or other aspects of your daily routine. If you smoke, they will likely advise you to quit.

Your doctor may also prescribe medications or other treatments to help lower your cholesterol levels. In some cases, they may refer you to a specialist for more care.

Lowering cholesterol through diet

To help you achieve and maintain healthy cholesterol levels, your doctor may recommend changes to your diet.

For example, they may advise you to:

• limit your intake of foods that are high in cholesterol, saturated fats, and trans fats
• choose lean sources of protein, such as chicken, fish, and legumes
• eat a wide variety of high fiber foods, such as fruits, vegetables, and whole grains
• opt for baked, broiled, steamed, grilled, and roasted foods instead of fried foods
• avoid fast food and sugary, pre-packaged options when possible

Foods that are high in cholesterol, saturated fats, or trans fats include:

• red meat, organ meats, egg yolks, and high fat dairy products
• processed foods made with cocoa butter or palm oil
• deep-fried foods, such as potato chips, onion rings, and fried chicken
• certain baked goods, such as some cookies and muffins

Eating fish and other foods that contain omega-3 fatty acids may also help lower your LDL levels. For example, salmon, mackerel, and herring are rich sources of omega-3s. Walnuts, almonds, ground flaxseeds, and avocados also contain omega-3s.

Cholesterol medications

In some cases, your doctor might prescribe medications to help lower your cholesterol levels.

Statins are the most commonly prescribed medications for high cholesterol. They block your liver from producing more cholesterol.

Examples of statins include:

• atorvastatin (Lipitor)
• fluvastatin (Lescol)
• rosuvastatin (Crestor)
• simvastatin (Zocor)

Your doctor may also prescribe other medications for high cholesterol, such as:

• niacin
• bile acid resins or sequestrants, such as colesevalam (Welchol), colestipol (Colestid), or cholestyramine (Prevalite)
• cholesterol absorption inhibitors, such as ezetimibe (Zetia)
• PCSK9 inhibitors, such as alirocumab (Praluent) and evolocumab (Repatha)

Some products contain a combination of drugs to help decrease your body’s absorption of cholesterol from foods and reduce your liver’s production of cholesterol. One example is a combination of ezetimibe and simvastatin (Vytorin). Learn more about the drugs used to treat high cholesterol.

Home remedies to lower cholesterol naturally

In some cases, you may be able to lower your cholesterol levels without taking medications. For example, it may be enough to eat a nutritious diet, exercise regularly, and avoid smoking tobacco products.

Some people also claim that certain herbal and nutritional supplements may help lower cholesterol levels. For instance, claims have been made about:

• garlic
• hawthorn
• astragalus
• red yeast rice
• plant sterol and stanol supplements
• blond psyllium, found in psyllium seed husk
• ground flaxseed

However, the level of evidence supporting these claims varies. Also, the Food and Drug Administration (FDA) hasn’t approved any of these products for treating high cholesterol. More research is needed to learn if they can help treat this condition.

Always talk with your doctor before taking any herbal or nutritional supplements. In some cases, they might interact with other medications you’re taking.

You can’t control the genetic risk factors for high cholesterol. However, lifestyle factors can be managed.

To lower your risk of developing high cholesterol:

• Eat a nutritious diet that’s low in cholesterol and animal fats, and high in fiber.
• Avoid excessive alcohol consumption.
• Maintain a moderate weight.
• E.xercise regularly.
• Avoid smoking.

Follow your doctor’s recommendations for routine cholesterol screening. If you’re at risk of high cholesterol or coronary heart disease, they will likely encourage you to get your cholesterol levels tested on a regular basis.

In most cases, high cholesterol has no symptoms. But without treatment, high cholesterol can cause serious health issues. The good news is that your doctor can help you manage this condition, and in many cases, can help you avoid complications.

To learn if you have high cholesterol, ask your doctor to test your cholesterol levels, especially if you’re 20 years or older. If they diagnose you with high cholesterol, ask them about your treatment options.

To lower your risk of complications from high cholesterol, practice healthy lifestyle habits and follow your doctor’s recommended treatment plan.

Eating a balanced diet, exercising regularly, and avoiding tobacco products may help you achieve and maintain healthy cholesterol levels. It could also help lower your risk of complications from high cholesterol.

Blood test for HDL cholesterol (high density) CMD laboratory in Moscow. Call: 8 (495) 120-13-12

Research method

• Colorimetric

High-density lipoproteins (HDL) are considered an anti-atherogenic fraction of lipoproteins, they are involved in the transport of cholesterol from peripheral tissues to the liver (reverse or afferent transport of cholesterol). The main HDL proteins are apolipoproteins A-I and A-II. It is in the composition of HDL that excess cholesterol is removed from the body. Therefore, HDL cholesterol is considered “good” cholesterol.

Main structural components of HDL

• Diagnosis of the risk of atherosclerosis and cardiovascular diseases.

Reference values ​​(standard version):

Age, years	Men	Women	Units
<1	0.36 – 1. 62	0.49 – 1.78	mmol/l
15	0.64 – 1.90	0.64 – 1.9
5 – 10	0.99 – 1.94	0.93 – 1.89
10 – 15	0.96 – 1.92	0.96 – 1.82
15 – 20	0.78 – 1.63	0.91 – 1.92
20 – 25	0.78 – 1.63	0.86 – 2.05
25 – 30	0.81 – 1.63	0.96 – 2.15
30 – 35	0.73 – 1.63	0.94 – 2.00
35 – 40	0.75 – 1.61	0.88 – 2.13
40 – 45	0.7 – 1.74	0.88 – 2.28
45 – 50	0.78 – 1.66	0.88 – 2.26
50 – 55	0.73 – 1.63	0.96 – 2.39
55 – 60	0. 73 – 1.84	0.96 – 2.36
60 – 65	0.78 – 1.92	0.99 – 2.39
65 – 70	0.78 – 1.95	0.91 – 2.49
> 70	0.80 – 1.95	0.86 – 2.39

In accordance with the following international and domestic recommendations:

Cardiovascular Prevention 2017. Russian national guidelines Russian Society of Cardiology, National Society of Preventive Cardiology, Russian Society for the Prevention of Noncommunicable Diseases

Expert Panel on Integrated Guidelines for Cardiovascular Health and Risk Reduction in Children and Adolescents, 2012

National Cholesterol Education Program. ATP III Guidelines At-A-Glance. Quick Desk Reference, 2002 Public Health Service National Institutes of Health National Heart, Lung, and Blood Institute.

Provided comments on the HDL-cholesterol test.

Optimal values ​​- more than 1.55; low values ​​(increased risk of cardiovascular diseases) – less than 1.04 mmol / l.

Sample result:

Please note that the interpretation of research results, diagnosis, and treatment, in accordance with Federal Law No. doctor of the relevant specialization.

Lipidogram (cholesterol, triglycerides, HDL, LDL, VLDL, C/A) – Protos Medical Center

Lipidogram allows you to assess the atherogenicity (the tendency to develop atherosclerosis) of blood plasma even at normal levels of total cholesterol. In the study of the lipid profile, indicators such as triglycerides, total cholesterol (cholesterol), high, low and very low density lipids are determined. The coefficient of atherogenicity is calculated.

Cholesterol is an important organic substance. It is synthesized mainly by the liver (endogenous cholesterol), and also partially enters the body with food (exogenous cholesterol). Cholesterol forms the cell membranes of all organs and tissues of the body, is a precursor of steroid hormones necessary for full development, growth and puberty, takes part in the synthesis of bile acids, which ensure the absorption of nutrients from the intestines. Cholesterol circulates in the blood in combination with lipoproteins.

High-density lipoprotein (HDL) removes excess free cholesterol accumulated in peripheral cells. They transport cholesterol to the liver, where it is catabolized to form fatty acids, or pass it on to very-low-density lipoproteins (VLDL), whereby the latter are converted into low-density lipoproteins (LDL). HDL are anti-atherogenic factors that prevent the formation of atherosclerotic plaque in the vessel. Low HDL indicates the possibility of developing the disease.

Total blood cholesterol is 60-70% represented by LDL, which are able to linger in the vascular wall and promote the accumulation of cholesterol in tissues. It is the levels of LDL and, to a lesser extent, total cholesterol in blood plasma that determine the risk of developing atherosclerosis and cardiovascular diseases. Even if the cholesterol rate is maintained, an increase in LDL indicates the atherogenic properties of blood lipids.

Triglycerides are a combination of fatty acid esters and glycerol and are the main source of energy for the body. The predominant amount of triglycerides is in adipose tissue, and only a small level is determined in the blood. They come from food or are resynthesized in the liver. Most triglycerides are transported in the blood as very low density lipoproteins (VLDL). Elevated triglyceride levels are often combined with diabetes mellitus, obesity, arterial hypertension, and changes in other lipid profile indicators.

The coefficient of atherogenicity is calculated on the basis of lipid metabolism indicators: KA = (total cholesterol – HDL) / HDL or KA = (LDL + VLDL) / HDL. An atherogenic coefficient that exceeds the normal range indicates an increased risk of cardiovascular disease.

Other risk factors for cardiovascular disease need to be taken into account when deciphering the lipid profile. These include age, gender, hereditary predisposition to dyslipidemia and diseases of the heart and blood vessels, impaired carbohydrate metabolism (diabetes mellitus), high blood pressure, obesity, smoking, alcohol consumption, and kidney pathology.