What You Need To Know About Cholesterol
Your complete guide
Cholesterol is a wax-like, fatty substance that belongs to a class of fat known as lipids. It is found in the blood and within all our cells. Our body needs cholesterol for its daily function.
Contrary to popular opinion, some cholesterol is important for good health. This substance is produced in the liver and is essential for producing vitamin D and steroid hormones. Cholesterol is also key in producing sex hormones like testosterone, estrogen, and progesterone.
Cholesterol is produced in the liver, then transported by the blood to different parts of the body.
But while cholesterol provides many benefits for the body, it can be dangerous to health in high amounts. It is important to know what you're eating to keep cholesterol levels in check.
Types of cholesterol
Cholesterol is divided into two main groups:
Good (HDL) cholesterol
Bad (LDL) cholesterol
What is HDL cholesterol?
High-density lipoproteins (HDL) are considered good cholesterol. This class of fat helps to absorb other forms of cholesterol in the blood before returning them to the liver.
The liver helps to flush cholesterol from the body, reducing the chances of a dangerous buildup in the blood. Healthy levels of HDL cholesterol can reduce the risk of stroke and heart disease.
What is LDL cholesterol?
Low-density lipoproteins (LDL) are the most common type of cholesterol and are often condemned for their health impact. LDL transports cholesterol to the arteries, where it can accumulate. This can cause plaque to build up in blood vessels, blocking blood flow to essential parts of the body and leading to a high risk of heart disease and stroke.
Other types of cholesterol
Very low-density lipoproteins (VLDLs) are also marked for their dangerous impact on health.
VLDLs increase the buildup of artery plaque. However, while VLDL and LDL produce similar, unhealthy effects, they transport different materials. LDL carries mainly cholesterol, whereas VLDL moves triglycerides, another type of fat found in the body.
What is high cholesterol?
High cholesterol is a common condition affecting about 38% of US adults. It is defined by total blood cholesterol levels exceeding or equal to 200 mg/dL.
This condition is a global issue. In 2008, 39% of adults worldwide had raised cholesterol levels. Between 2015 and 2018, almost 12% of US adults had cholesterol levels higher than 240 mg/dL.
Often tagged a “silent killer,” high cholesterol requires quick attention. The higher the level of cholesterol in the blood, the greater the chance of developing cardiovascular disease. This condition causes 4.4 million deaths around the world annually and is responsible for 7.8% of all deaths.
Who is at risk of high cholesterol?
High cholesterol may result from your genetic makeup, otherwise known as familial or primary hypercholesterolemia. For most people, however, it is caused by lifestyle factors such as poor diet and lack of exercise.
In such cases, the condition is known as acquired hypercholesterolemia. For others, a health condition, such as an underactive thyroid, can cause cholesterol levels to increase.
Family history
It isn’t uncommon for family members to share similar cholesterol levels. Parents may pass mutated genes to their children, affecting how the body processes cholesterol and increasing the risk of high cholesterol levels. Familial hypercholesterolemia may affect the process through which the liver breaks down cholesterol.
This condition also makes it more challenging for the body to remove LDL cholesterol from the blood.
Unhealthy lifestyle habits
Simple daily activities can play a role in cholesterol accumulation.
Diet
Dietary choices can determine how much cholesterol is introduced to the body. Eating meals high in saturated fat, e.g., dairy produce and fatty meat can raise LDL cholesterol levels.
It is recommended that only 10% of daily calories should be obtained from such fat.
Likewise, trans fat found in many fried and baked goods can worsen LDL cholesterol.
Inactivity
A sedentary lifestyle containing little to no exercise is bad for cholesterol levels. Constant inactivity can lower HDL levels in the body.
Smoking
Smoking can have a major influence on cholesterol levels, lowering amounts of HDL. This effect is most notably found in female smokers.
In addition to lowering good cholesterol, smoking can increase levels of LDL.
Stress
When the body is constantly faced with stressful situations, this can impact cholesterol levels. Corticosteroids (stress hormones) are produced in high-stress environments and can push the body to produce more cholesterol.
Alcohol
Certain amounts of alcohol can cause abnormal cholesterol levels. In men, having more than two drinks a day can increase cholesterol in the body. For women, one drink alone can cause higher cholesterol levels.
Managing other medical conditions
Certain illnesses or factors, sometimes caused by unhealthy habits such as inactivity or a poor diet, raise the risk of high cholesterol, for example, being overweight or obese.
You may also have an increased risk of high cholesterol if you live with:
Diabetes
Chronic kidney disease
HIV
Sleep apnea
PCOS
Managing an illness with certain drugs
Some medications are linked to increased LDL cholesterol production, such as:
Blood pressure medicines
Drugs to manage irregular heartbeat
Beta-blockers
Chemotherapy medicines
Retinoids for acne
Age or gender
Anyone can be affected by high cholesterol, even children. However, it is most commonly observed in people aged 40–59. As we age, our metabolism slows, which affects the liver’s efficiency in ridding the body of LDL cholesterol.
Men aged 20–39 have a greater chance than women of developing high cholesterol.
Certain hormones, such as estrogen, offer protection against cholesterol. Menopausal women are at a greater risk of high cholesterol because estrogen production is decreased.
Different ethnicities
Ethnicity can play a role in cholesterol levels. Some populations, like non-Hispanic white people, are at higher risk of increased cholesterol. Asian Americans also fall into this group.
Hispanic Americans are very likely to run low on HDL (good) cholesterol, while African Americans are most likely to have high levels of good cholesterol.
Symptoms
High cholesterol operates silently — without symptoms.
However, raised cholesterol levels to increase the risk of developing a cardiovascular disease like angina, heart attack, or stroke.
Complications from high cholesterol
A person with high cholesterol levels is open to several health complications.
High cholesterol leads to the buildup of plaque in the artery walls. In large amounts, pieces of plaque can break away, leading to blood clots.
A clot can become so large that it completely or substantially prevents blood flow in a coronary artery. This can lead to severe cases of coronary heart disease.
Chest pain or even a heart attack may result when blood flow to the heart is blocked or decreased.
Plaque can also build up in different parts of the body, causing stroke and peripheral arterial disease.
Causes
Some risk factors of high cholesterol are outside our control, while others are not.
Family hypercholesterolemia, a genetic condition, can lead to high LDL levels. This condition is usually the result of a variant in the gene for the LDL receptor. High cholesterol resulting from this is not easily avoided.
However, other causes are linked to lifestyle choices. The food we eat influences our body systems; trans and saturated fats are known causes of high cholesterol.
The liver makes all the cholesterol our body needs for daily functioning. Consuming foods high in these fats raises cholesterol levels, leading to an increased risk of health complications.
Also, living a sedentary (inactive) lifestyle can reduce the body’s production of good cholesterol.
Certain medical conditions can lead to high cholesterol, including:
Diabetes
Hypothyroidism
Chronic kidney disease
Lupus
Obesity
Diuretics, immunosuppressive medications, drugs used to manage heart arrhythmia, and other medications can lead to a buildup of cholesterol.
What raises cholesterol?
Cholesterol levels can be raised by a diet filled with animal fats. These are found in red meat like beef, pork, and lamb. Fried and processed foods are also high in cholesterol.
Palm oil has been linked to higher saturated fats than other vegetable oils. However, there is inconclusive evidence confirming this.
Other causes of increased cholesterol levels include sedentary behaviors and inactive lifestyles, and habits like cigarette smoking and drinking alcohol.
Certain illnesses and medications also raise blood cholesterol.
Risk factors
Different circumstances can increase the risk of developing high cholesterol, including:
Age
Sex
Ethnicity
Family history
Lifestyle habits such as diet and exercise
Smoking
High-stress environments
Alcohol use
Existing health conditions
Certain medicines
Tests that measure high cholesterol
Blood tests can measure the amount of cholesterol and specific fats in the blood. These tests provide information on the risk of heart attack and other forms of heart disease.
Cholesterol tests measure levels of:
LDL
HDL
Total cholesterol
Triglycerides
VLDL
Recommended cholesterol levels
Cholesterol is usually measured in milligrams per deciliter (mg/dL). According to the National Institutes of Health, after a blood test, the following levels are healthy, depending on your age and gender:
Guidelines for healthy cholesterol levels
People aged 20 and over at low risk of cardiovascular disease should stay informed about their blood cholesterol. Anyone within this group should get their levels checked every five years¹.
Managing dietary cholesterol and reducing habits like smoking and drinking alcohol can improve cholesterol levels, as can introducing exercise as part of a daily routine.
Sources
How and when to have your cholesterol checked | Centers for Disease Control and Prevention (CDC)
Treatments
Cholesterol treatments primarily aim to lower unhealthy levels of LDL. However, simply lowering levels isn’t enough. For truly effective management, these measures should also look to prevent heart disease.
High cholesterol may be treated by adopting practices that improve heart health, including:
Healthy eating
Avoiding a trans and saturated fat-heavy diet is a requirement for managing high cholesterol. A Mediterranean diet¹ high in vegetables, legumes, fruit, nuts, grains, seafood, and even moderate amounts of red wine can be highly effective in managing levels of bad cholesterol.
Weight management
For anyone overweight and dealing with high cholesterol, losing weight can be beneficial for overall health. The reduced weight will decrease the amount of fat in the body and the total amount of cholesterol.
Exercise
Increased physical activity is always encouraged for managing cholesterol levels. Everyone, including people looking to manage blood cholesterol, should aim for 30 minutes of exercise five days a week.
Properly coping with stress
Living with constant stressors can increase your levels of bad cholesterol. By engaging in proper stress management, LDL levels may be reduced, and HDL cholesterol will be increased.
Quitting smoking
When cigarettes are avoided, this can increase HDL levels. The surge of HDL can help to clear LDL cholesterol from the artery wall.
Cholesterol medication
Sometimes, lifestyle changes are not enough to significantly improve cholesterol levels. In addition to physical exercise, a balanced diet, stress management, and other improvements, medication can also be introduced.
Statins
Statins are the most commonly recommended drugs for high cholesterol. They have been shown to reduce the risk of heart attack and stroke in cases of high LDL cholesterol.
However, statins may increase blood sugar, and people living with prediabetes, obesity, or metabolic syndrome may be at risk of diabetes when taking these drugs.
Another side effect of statins is irregular readings on liver enzyme tests. Although possible, muscle damage is a rare effect of using statins².
Medicine for familial hypercholesterolemia (FH)
When high cholesterol is hereditary, medication can manage the condition. Options include:
Mipomersen
Ezetimibe
Lomitapide
Your doctor may also prescribe ezetimibe if statins cause unwanted side effects.
However, caution is required, as these drugs can damage the liver.
Bile acid sequestrants
There are cases where cholesterol levels remain high despite all interventions. When statins and other medicines cannot sufficiently lower raise levels, bile acid sequestrants may be prescribed.
Bile acids are important for digesting fats and oils, keeping them in the intestine instead of re-absorbing into the blood.
Like other drugs, bile acid sequestrants can cause side effects. These include diarrhea and weakening the effects of other drugs. They can also cause high triglyceride levels.
PCSK9 inhibitors
These medicines are injected into the skin every two to four weeks. PCSK9 is prescribed to manage the risk of heart attack or stroke. It is also recommended when high cholesterol is genetic.
Users of these inhibitors may experience itching, pain, or swelling at the injection site.
Lifestyle changes
For a full target treatment of high cholesterol, lifestyle changes must accompany any prescribed drugs. This may require:
Quitting smoking and alcohol
Eating highly nutritious meals
Exercising
Sources
Mediterranean diet and health status: Active ingredients and pharmacological mechanisms (2020)
Blood cholesterol: Treatment | NIH: National Heart, Lung, and Blood Institute
Prevention
Age, genetic factors, and ethnicity are impossible to control. However, it’s possible to manage the following when planning to avoid high cholesterol:
Eating heart-healthy meals
Cutting down on alcohol
Reducing or quitting smoking
Keeping weight within healthy limits
You should also keep an eye out for high cholesterol by getting your levels tested regularly.
Doctors & specialists
When to see a doctor
It’s important to get expert insight when tests reveal higher-than-recommended levels of bad cholesterol.
People at high risk of increased cholesterol should visit a healthcare professional for routine checks.
Which types of doctors/specialists treat cholesterol?
Cholesterol can be properly managed through the joint effort of medical professionals. For instance, an endocrinologist manages conditions that impact hormones. This expert can be joined by a general practitioner to control the causes of high cholesterol.
Likewise, a lipidologist who treats conditions caused by fatty substances in the blood can give directions on lowering cholesterol.
Because diet goes a long way in overcoming cholesterol levels, a dietician is also required on the care team. This expert can advise the right diet to lower cholesterol.