Lipids: Examples, function, and associated conditions

Share on Pinterest

Lipids are fatty compounds that play an essential role in the human body. As components of cell structures, they are present in all parts of the body.

According to a 2023 article, lipids can dissolve in some bodily fluids but not in water. This chemical property is partly what makes lipids so distinctive and important.

Lipids can build up around many organs and structures of the body. People often refer to these lipid stores as “fat.”

A different 2023 article notes that there are many different types of lipids, including:

• phospholipids
• sterols
• triglycerides (fats and oils)
• waxes

Lipoproteins

Lipids may also combine with other biochemicals to form more complex substances.

Since lipids do not dissolve in water, they need help traveling around watery fluids. Proteins called apolipoproteins combine with lipids to form water-soluble lipoproteins.

Typically, lipoproteins contain apolipoproteins alongside a complex of phospholipids, triglycerides, and cholesterol.

Lipoproteins include:

• low-density lipoproteins (LDL)
• high-density lipoproteins (HDL)
• very low-density lipoproteins (VLDL)
• intermediate-density lipoproteins (IDL)
• chylomicrons

According to the initial 2023 article previously mentioned, lipids serve a variety of important bodily functions. The table below outlines some key lipids and their associated functions.

As the article explains, lipids are small molecules that are themselves made of even simpler components. Some key lipids and their associated anatomical structures are outlined below:

• Triglycerides: Fatty acids typically contain an even number of carbon atoms. Triglycerides help store energy, insulate cells, and help with the absorption of fat-soluble vitamins.
• Phospholipids: Phospholipids are arranged in a bilayer manner. They provide protection for cells and are a barrier for certain molecules.
• Steroids: Steroids consist of four fused rings. Cholesterol is an important type of steroid.
• Wax: Waxes are combinations of fatty acids and long alcohol molecules.

There are many lipid-related health conditions. Of these, some of the most significant are those involving high lipid levels. Some examples are outlined below.

High LDL cholesterol

High blood levels of low-density lipoprotein (LDL) cholesterol can increase a person’s risk of certain conditions, including:

• heart attack
• stroke
• diabetes
• artery disease
• high blood pressure

The American Heart Association (AHA) recommends that individuals who are considered healthy by clinical standards aim for an LDL level below 100 milligrams (mg) of cholesterol per deciliter (dL) of blood (mg/dL).

However, people with a history of heart attack or stroke who are already taking cholesterol-lowering medications may need to aim for an LDL level of 70 mg/dL or lower.

High triglyceride blood levels

The National Institutes of Health (NIH) explains that high triglyceride blood levels can cause complications, such as heart disease and stroke. Doctors define borderline high triglyceride blood levels as anything between 150 and 199 mg/dL. Levels between 200 and 499 mg/dL are high, and anything above 500 mg/dL is very high.

Phospholipids

Antiphospholipid syndrome is an autoimmune condition in which the immune system produces abnormal antibodies called antiphospholipid antibodies. These abnormal antibodies target proteins attached to phospholipids, and this process makes the blood more likely to clot.

According to a 2023 review, antiphospholipid syndrome does not always cause symptoms, However, it can cause blood clots and pregnancy loss.

As the previously mentioned 2023 article explains, doctors order tests that require collecting a blood sample that is analyzed in a laboratory to help evaluate lipid levels.

Because triglyceride levels vary throughout the day, and rise after meals, blood samples must be collected after a 12-hour fast. For the most accurate results, individuals are advised to not take any medications that can affect blood lipid levels and to avoid lipid testing during periods of illness or stress.

The treatment for high lipid levels and lipid-related conditions varies from case to case. Some potential treatment options are outlined below.

Treating high lipid levels

According to the AHA, the following lifestyle adaptations can help lower high lipid blood levels to recommended levels:

• following a heart-healthy eating plan that is high in nutritious foods like fruits and vegetables and low in substances like sugar and full fat
• staying physically active, such as exercising
• if doctor-prescribed, losing weight to help maintain a moderate weight
• if a person smokes, quitting smoking
• if a person drinks alcoholic beverages, limiting alcohol consumption

If these adaptations are not sufficient, doctors may recommend medications to help lower lipid blood levels. According to the AHA, these medications may include:

• Statins: These medications help prevent cholesterol formation in the liver, thereby reducing the amount of cholesterol circulating in the blood. Examples include:
  • atorvastatin (Lipitor)
  • pravastatin (Pravachol)
  • simvastatin (Zocor)
• Bile acid sequestrants: These medications cause the intestines to get rid of excess cholesterol. Examples include:
  • colestipol (Colestid)
  • colesevelam HCL (WelChol)
  • cholestyramine (e.g., Questran, Prevalite, and Locholest).
• Fibrates: These medications can significantly lower triglyceride levels and can also lead to a mild decrease in LDL cholesterol. Examples include:
  • gemfibrozil (Lopid)
  • clofibrate (Atromid-S)
  • fenofibrate (e.g., Lofibra, Tricor, and Triglide)
• Omega-3 fatty acid ethyl esters: These are fish oil derivatives that people can use in combination with adapting eating patterns to help lower high triglyceride levels. Examples include:
  • Lovaza
  • Vascepa
  • Omtryg

Treating antiphospholipid syndrome

Another 2023 article states that there is no cure for antiphospholipid syndrome. Instead, management focuses on using medications to prevent blood clots and taking steps like consistently attending scheduled prenatal care visits to help ensure safer pregnancies.

As the AHA explains, the same lifestyle tips that can help treat high lipid levels can also help maintain recommended lipid levels. These include:

• following a heart-healthy eating plan that is high in nutritious foods like fruits and vegetables and low in substances like sugar and full fat
• staying physically active, such as exercising
• if doctor-prescribed, losing weight to help maintain a moderate weight
• if a person smokes, quitting smoking
• if a person drinks alcoholic beverages, limiting alcohol consumption

It is important to note that not everyone will respond to lifestyle adaptations in the same way. For instance, some individuals may need to get more physical activity than others to maintain the same recommended lipid levels.

People can talk with their doctor for further advice on how to lower their lipid levels and maintain recommended levels.

Lipids are fatty compounds that perform various essential functions in the body, such as storing energy, insulating cells, and controlling which molecules enter and exit cell membranes.

Despite their many important functions, high lipid blood levels can cause serious health complications, such as heart attack and stroke. Doctors advise and support people with treatment plans to lower and maintain recommended blood lipid levels.

Some recommendations include following a heart-healthy eating plan, staying physically active, and if a person smokes, quitting smoking.

If lifestyle modifications do not succeed in lowering and maintaining recommended blood lipid levels, doctors may recommend medications, such as statins, bile acid sequestrants, and fibrates.

Anyone who is concerned about their blood lipid levels can talk with their doctor for further advice.