Cholesterol Definition

Cholesterol is a fatty and waxy substance found in every cell of our body. It is produced by the liver and plays an essential role in the formation of bile juice, which is responsible for the process of digesting fats. It is utilized by the body to build healthy new cells as well as essential hormones. Cholesterol travels in the body in the form of lipoproteins and is made up of fats and proteins. Cholesterol is vital for our body when present at a healthy level. It can be good and bad for health.

What Is The Function Of Cholesterol?

Cholesterol is responsible for performing four essential functions which are as follows:

  • It helps in building the structure of the cell membrane.
  • It helps the body in the production of vitamin D.
  • And is responsible for making the bile juice in the intestine
  • It helps in the production of essential hormones.

What Is High Cholesterol Level?

It is the condition in which the cholesterol level increases in the blood, also called hyperglycemia.
A person with high cholesterol has fatty deposits developed in the blood vessels. When these fatty deposits grow, it is difficult for blood to flow through your arteries. Sometimes, these harmful deposits can break to form a clot that can lead to a heart attack or stroke.
High cholesterol can be inherited, but it’s often the result of unhealthy lifestyle choices, which make it preventable and treatable. A healthy diet, regular exercise, and sometimes medication can help reduce it.
They are no visible symptoms present for high cholesterol. Therefore, it is necessary to get the cholesterol levels checked frequently. Some of the reasons behind high cholesterol levels include family history, unhealthy diet or lifestyle, overweight, or smoking.
It can increase the risk of various health complications, such as coronary heart diseases and stroke.

Types Of Cholesterol:

Cholesterol is classified into two types – LDL (Low-Density Lipoproteins) and HDL (High-Density Lipoproteins).
There are following types of cholesterol:

  • Low-Density Lipoproteins (LDL)
  • High-Density Lipoproteins (HDL)
  • Triglycerides
  • Lp(a) Cholesterol

Low-Density Lipoproteins (LDL):

Low-Density Lipoproteins (LDL) is also called bad cholesterol or plaque builder. When there is a high level of LDL inside the blood, it gets stored in the arteries, thus blocking the blood flow. The LDL combined with other substances in the arteries to form plaque, which is a thick hard deposit that builds in arteries and cause blockage or resistance in arteries. It can lead to a condition called atherosclerosis. If the less blood flows inside the arteries, it gives rise to the condition called ischemia, or if the clop appears inside the arteries, it leads to the condition such as heart attack or stroke.

High-Density Lipoproteins (HDL):

High-Density Lipoprotein (HDL) is also called as Good cholesterol as HDL protects against the disease such as heart attack. HDL carries one- fourth of our blood. It is responsible for carrying the blood from the arteries back to the liver; therefore HDL is known for eating the bad cholesterol.


Triglycerides are a type of fat that is present inside the body. They are extracted from the food such as butter and oils or can be retrieved with the extra calories we take. The increased level of triglycerides in the body is due to the overweight, sedentary lifestyle, smoking, excess use of alcohol, or having a carbohydrate-rich diet. The patients who suffer from diabetes have high triglycerides due to uncontrolled sugar levels inside the body, and the patient with heart diseases and diabetes are at higher risk of high triglycerides.

Lp(a) Cholesterol:

It is a type of low-density lipoproteins (LDL), a genetic variation in LDL. An increased level of Lp(a) inside the blood leads to the development of plaque or premature fatty deposits inside the arteries. Some of the researches show that it is an independent risk factor for coronary heart diseases. The normal Lp(a) level is 30 milligrams per deciliter (mg/dl).

What Causes High Cholesterol?

The liver is responsible for producing cholesterol, but it can also be retrieved with the food we eat.
Several factors are responsible for causing it which is as follows:


Overweight or obese patients are at increased risk of high cholesterol as overweight patients have a higher level of triglycerides.

Family History

Family history is also a factor of High cholesterol as research has shown that it runs in families.

Inactive Lifestyle

People with a sedentary lifestyle are at higher risk of high cholesterol as the inactive lifestyle lowers the level of High-Density Lipoproteins.

Calorie Rich food

Having calorie-rich foods such as sugar, baked items, chocolates, fried items increases the risk of high cholesterol.


Smoking causes high cholesterol as the cigarette contains a substance, acrolein, which stops the production of HDL.

Other Causes

  • Diabetes
  • Renal diseases
  • Disorder of liver
  • Drugs which increases the production of LDL
  • Pregnancy
  • High Blood Pressure
  • Old Age
  • Inactivity

Diagnosis Of High Cholesterol

There is no specific sign and symptoms of High cholesterol. A blood test called a lipoprotein profile can help to diagnose it. The test is done on an empty stomach, and it measures the specific levels of lipids in the blood.
The lipid profile includes the following:
Total Cholesterol: It measures all the cholesterol in each lipoprotein particle.
Low-Density Lipoproteins: It measures the LDL levels inside the blood as it contributes to depositing excess cholesterol in the lining of blood vessels.
High-Density Lipoproteins: It measures the HDL level that is the good cholesterol in the blood responsible for taking the cholesterol from the arteries to the liver.
Triglycerides: It measures the triglycerides in all the lipoproteins particles. In addition to the blood test, the doctor also performs a physical examination and collects the patient’s complete history for the diagnosis of high cholesterol.

Symptoms Of High Cholesterol

There are no signs and symptoms present for the high cholesterol. Here are some reasons that can lead to cause it which are:

Risk Factors Of High Cholesterol

There are certain risk factors for high cholesterol which are as follows:

  1. People who smoke are at higher risk of high cholesterol.
  2. Low HDL levels in the blood give rise to the chances of high cholesterol.
  3. People with a family history of heart diseases and hypertension are at higher risk of high cholesterol.
  4. Age Is the risk factor for it. Men with 45 years or above age and women with 55 years and above are at higher risk.
  5. Diabetic patients are at high risk of high cholesterol due to imbalance sugar levels in the blood.

Treatment Of High Cholesterol

Treatment of high cholesterol means reducing the level of Low-Density Lipoproteins (LDL) as it is bad cholesterol and the major risk factor for chronic diseases such as heart attack and stroke.
It can be treated in two ways

  1. Lifestyle Changes
  2. Drug Treatment

Lifestyle Changes

People with high LDL levels are advised to change their lifestyle to treat high cholesterol. It can be achieved by taking the low cholesterol foods, practicing the daily exercises and, managing a healthy weight.

Low Cholesterol Diet

Low cholesterol diet includes the food with low saturated fats, It helps in lowering the LDL levels and responsible for maintaining the desired weight.


A 30-minute exercise is mandatory to prevent high cholesterol. The physical activity helps in increasing the HDL levels and lowering the LDL levels.

Managing Healthy Weight

Overweight patients are at higher risk of high cholesterol, therefore obese patients need to reduce their weight to decrease the LDL level in the blood.

Drug Treatment

Drug treatment involves the use of medication to control high cholesterol. Following are the medicines that control the high cholesterol:

  • Statin Medications
  • Bile acid sequestrants
  • Cholesterol absorption inhibitors
  • Fibric acid
  • Nicotinic acid

Prevention Of High Cholesterol

Living a healthy lifestyle can prevent high cholesterol.

    1. Try to eat healthily and avoid foods with saturated fats.
    2. Avoid bad fats like saturated and trans fats increase the LDL level.
    3. Regular exercise helps people in preventing High cholesterol.
    4. Taking omega 3 fatty acids to reduce the level of triglycerides and helps in preventing high cholesterol.
    5. Weight loss help in preventing high cholesterol as it lowers the triglyceride level and raises the level of HDL.
    6. Give up smoking.
    7. Limit your alcohol intake.
    8. Increased fiber intake helps in preventing high cholesterol.
    9. Take proper medication as prescribed by the doctor to control the high cholesterol.
    10. 30 minutes exercise is necessary to prevent high cholesterol.

High Cholesterol FAQs

Question 1

What is the normal cholesterol level?
Answer: Normal cholesterol level is 200 milligrams per deciliter (mg/dL).

Question 2

What are LDL and HDL?
Answer: LDL and HDL are two types of lipoproteins. LDL is bad cholesterol, and HDL is the good cholesterol.

Question 3

What are the Normal Ranges for LDL and HDL inside the body?
Answer: The normal range for LDL is less than 100 mg/dL whereas, the normal range for HDL is 40mg/dL or higher.

Question 4

What Causes High Cholesterol in your body?
Answer: The factors that cause high cholesterol are overweight, diabetes, poor diet, age, and smoking. Eating fatty foods can also increase your cholesterol level.

Question 5

What are the symptoms of high cholesterol?
Answer: There are no specific symptoms present for High Cholesterol.

Question 6

How high cholesterol is diagnosed?
Answer: Since there are no symptoms to know whether is a person is suffering from this disease. It is recommended to take a simple blood test to reveal your cholesterol level.
Men older than 35 years and women 45 years of age should have their cholesterol checked regularly. People in their 20s and teenagers may need to be checked if they are overweight or have a family history of this disease. Consult your doctor first.

Question 7

Can I prevent the problem of high cholesterol?
Answer: Eating healthy, nutritious food, and exercising are the best ways to reduce the risk of developing high cholesterol. Take foods with saturated and healthier fats. This includes lean meats, fruits, nuts, and low-fat dairy items. Try to avoid foods (such as fried and packaged foods) as it contains trans fat which is harmful to health.

Question 8

Can the risk of heart diseases be lowered by lowering cholesterol levels?
Answer: The risk of heart disease is significantly lower when you have low total cholesterol or low LDL.


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