high-density lipoprotein

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Detailed diagram showing the transport of lipoproteins in the human body, illustrating how dietary fats and cholesterol are absorbed in the small intestine, packaged into chylomicrons, and transported through lymphatic vessels and the bloodstream. The diagram traces the conversion of chylomicrons to VLDL, IDL, LDL, and HDL particles, highlighting their roles in fat and cholesterol delivery, storage, and recycling, with labeled pathways to the liver, muscle, and adipose tissue, and includes cellu

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high-density lipoprotein

biochemistry

Also known as: HDL

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June 29, 2026

Quick Summary

Detailed diagram showing the transport of lipoproteins in the human body, illustrating how dietary fats and cholesterol are absorbed in the small intestine, packaged into chylomicrons, and transported through lymphatic vessels and the bloodstream. The diagram traces the conversion of chylomicrons to VLDL, IDL, LDL, and HDL particles, highlighting their roles in fat and cholesterol delivery, storage, and recycling, with labeled pathways to the liver, muscle, and adipose tissue, and includes cellu — lipoprotein complexes Synthesis of lipoprotein complexes in the small intestine, liver, and blood plasma and their delivery to peripheral tissues of the body.

High-density lipoprotein (HDL), often called "good cholesterol," is a type of lipoprotein found in blood plasma. It is characterized by a high proportion of protein and lower amounts of triglyceride and cholesterol compared to other lipoproteins.1

Lipoproteins are essential complexes that transport lipids throughout the body via the circulatory system. HDL's primary function is to collect excess cholesterol from the body's cells and transport it back to the liver for excretion. This process is believed to help prevent the buildup of cholesterol in artery walls, a condition known as atherosclerosis, which can lead to heart attacks and strokes. Higher levels of HDL cholesterol are generally associated with a reduced risk of cardiovascular disease.234

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lipid
High-density lipoproteins (HDL)
Lipoproteins of this class are the smallest, with a diameter of 10.8 nm and the highest protein-to-lipid ratio. The resulting high density gives this class its name. HDL plays a primary role in the removal of excess cholesterol from cells and returning…
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Lipoproteins of this class are the smallest, with a diameter of 10.8 nm and the highest protein-to-lipid ratio. The resulting high density gives this class its name. HDL plays a primary role in the removal of excess cholesterol from cells and returning…
Read More

nutritional disease
Cardiovascular disease
…LDL cholesterol, low levels of high-density lipoprotein (HDL) cholesterol, hypertension, and diabetes. However, the role of diet in influencing the established risk factors is not as clear as the role of the risk factors themselves in CHD. Furthermore, dietary strategies are most useful when combined with other approaches, such as…
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…LDL cholesterol, low levels of high-density lipoprotein (HDL) cholesterol, hypertension, and diabetes. However, the role of diet in influencing the established risk factors is not as clear as the role of the risk factors themselves in CHD. Furthermore, dietary strategies are most useful when combined with other approaches, such as…
Read More

metabolic disease
Lipoprotein disorders
… (IDL), low-density lipoproteins (LDL), and high-density lipoproteins (HDL). Disorders that affect lipid metabolism may be caused by defects in the structural proteins of lipoprotein particles, in the cell receptors that recognize the various types of lipoproteins, or in the enzymes that break down fats. As a result of such defects,…
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… (IDL), low-density lipoproteins (LDL), and high-density lipoproteins (HDL). Disorders that affect lipid metabolism may be caused by defects in the structural proteins of lipoprotein particles, in the cell receptors that recognize the various types of lipoproteins, or in the enzymes that break down fats. As a result of such defects,…
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nutritional disease
Blood lipoproteins
High-density lipoproteins, on the other hand, are thought to transport excess cholesterol to the liver for removal, thereby helping to prevent plaque formation. HDL cholesterol is inversely correlated with CHD risk; therefore intervention efforts aim to increase HDL cholesterol levels. Another blood lipoprotein form, the…
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High-density lipoproteins, on the other hand, are thought to transport excess cholesterol to the liver for removal, thereby helping to prevent plaque formation. HDL cholesterol is inversely correlated with CHD risk; therefore intervention efforts aim to increase HDL cholesterol levels. Another blood lipoprotein form, the…
Read More

therapeutics
Preventive medicine
… (LDL) level and a decreased high-density lipoprotein (HDL) level are significant risk factors. The total cholesterol level and elevated LDL level can be reduced by appropriate diet, whereas a low HDL can be raised by stopping smoking and increasing physical activity. If those measures do not provide adequate control, a…
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… (LDL) level and a decreased high-density lipoprotein (HDL) level are significant risk factors. The total cholesterol level and elevated LDL level can be reduced by appropriate diet, whereas a low HDL can be raised by stopping smoking and increasing physical activity. If those measures do not provide adequate control, a…
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therapeutics
The cardiovascular system
One form of cholesterol, high-density lipoprotein (HDL), is actually beneficial and helps to carry the harmful cholesterol out of the arterial wall. While some drugs will raise blood levels of HDL cholesterol, the most effective means of increasing it is to avoid smoking and to increase exercise.
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One form of cholesterol, high-density lipoprotein (HDL), is actually beneficial and helps to carry the harmful cholesterol out of the arterial wall. While some drugs will raise blood levels of HDL cholesterol, the most effective means of increasing it is to avoid smoking and to increase exercise.
Read More

trans fat
Health risks associated with trans fat
…fats also lower levels of high-density lipoprotein (HDL) cholesterol, which plays an important role in transporting cholesterol from cells and blood vessels to the liver, where cholesterol is metabolized for excretion. Levels of HDL are inversely correlated with the risk of heart disease, and therefore the depletion of HDL by…
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…fats also lower levels of high-density lipoprotein (HDL) cholesterol, which plays an important role in transporting cholesterol from cells and blood vessels to the liver, where cholesterol is metabolized for excretion. Levels of HDL are inversely correlated with the risk of heart disease, and therefore the depletion of HDL by…
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cholesterol
High-density lipoproteins (HDLs) may possibly transport excess or unused cholesterol from the tissues back to the liver, where it is broken down to bile acids and is then excreted. Cholesterol attached to LDLs is primarily that which builds up in atherosclerotic deposits in the blood…
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High-density lipoproteins (HDLs) may possibly transport excess or unused cholesterol from the tissues back to the liver, where it is broken down to bile acids and is then excreted. Cholesterol attached to LDLs is primarily that which builds up in atherosclerotic deposits in the blood…
Read More