Originally published: 30.OCT.2022
Last updated: 25.FEB.2024

Medically reviewed by Zara Fullerton, Senior Medical Content Manager

When you think of cholesterol, you might associate it with several negative side effects. However, did you know that cholesterol is vital for our bodies to function properly? That’s right, while too much cholesterol can be cause for concern, just the right amount is needed to support many important bodily functions

The function of cholesterol in the body can be a complex topic, but it certainly doesn’t have to be. This is everything you need to know about the primary functions of cholesterol including the risk factors of having too much and the benefits of having healthy levels.

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What is Cholesterol?

Cholesterol is a wax-like fatty substance that is essential for many important functions in the body. Your liver produces enough cholesterol to support these functions however you also get cholesterol from the food you eat. While our bodies do have a system for controlling excess cholesterol, if cholesterol levels become too high, it can lead to complications.

There are two types of cholesterol

  • Low-density lipoprotein (LDL): This is often known as ‘bad’ cholesterol, too much can lead to plaque buildup in the arteries. This is a risk for heart attack and stroke.

  • High-density lipoprotein (HDL): Also known as ‘good’ cholesterol, it supports the removal of LDL from the arteries and helps keep your cardiovascular system healthy.

Related article: 9 Causes of High Cholesterol

What are the Main Functions of Cholesterol?

#1 Cholesterol forms part of the cell membrane building blocks

Cholesterol makes up part of every cell in the body.

Cholesterol and phospholipids are two major lipids that make up cell membranes - these are what make up the outer layer of cells, and act as gatekeepers. Cell membranes have a double layer of lipids called phospholipids. Phospholipids are lipids that have a phosphate molecule attached to them.

Cholesterol is essential in cell membranes for 3 main reasons [1]:

  • Cholesterol supports cell membranes: Cholesterol is insoluble in water and is more rigid than surrounding molecules so it ensures that the cell membrane is structurally supported.

  • Cholesterol keeps cell membranes fluid: Cholesterol has different effects on the fluidity of cell membranes depending on temperature. It ensures the cell membranes do not become too rigid or too fluid despite changing temperatures

  • Cholesterol is necessary for the construction of special parts of the cell called lipid rafts: Lipid rafts are thought to be involved in the transportation of specific proteins that help prevent the infiltration of certain pathogens such as viruses and bacteria.

#2 Cholesterol produces key hormones

Cholesterol is necessary for the formation of key hormones [2].

Examples of steroid hormones include progestogens, glucocorticoids, mineralocorticoids, androgens, and estrogens. Your body’s hormone-producing glands use cholesterol to make hormones such as estrogen, testosterone, cortisol, and thyroid hormones.

This is how hormones are affected by cholesterol and vice versa.

  • Cholesterol and thyroid hormones: An underactive thyroid (hypothyroidism) and therefore a lower level of thyroid hormone production can lead to an increase in circulating LDL cholesterol in the blood [3]. It has also been shown that an overactive thyroid (hyperthyroidism) and therefore a higher level of thyroid hormone production may lead to a lower level of LDL cholesterol in the blood.

  • Cholesterol and female sex hormones: When circulating estrogen levels rise in the blood, LDL cholesterol levels decline. When circulating estrogen levels decline in the blood, LDL cholesterol levels increase. This may explain why there is a higher chance of heart disease in post-menopausal women [4].

  • Cholesterol and male sex hormones: As men age, their testosterone levels naturally decline. It has been shown that as testosterone levels decrease, LDL cholesterol begins to increase. Higher LDL cholesterol has also been shown in men who undergo androgen deprivation therapy (ADT), a therapy often used to lower testosterone in men with prostate cancer [5].

#3 Cholesterol plays a role in digestion

Cholesterol plays a role in digestion because it is an essential ingredient in the production of bile [6].

Bile is a substance that is produced in the liver and stored in the gallbladder. It is responsible for the breakdown and absorption of some nutrients into the body. Bile is an essential substance to have in the body, especially for the breakdown and digestion of dietary fats.

How do I know if my cholesterol levels are healthy?

One of the best ways to reduce the risk of cardiovascular diseases, such as heart disease and stroke, is to monitor your cholesterol levels. People with high cholesterol levels often experience little to no symptoms, so if you are concerned about your levels, be sure to speak with your healthcare provider.

If you would prefer to monitor your levels with LetsGetChecked, consider our Cholesterol Testing options. Online results will be available through your secure platform within 2-5 days of our lab receiving your sample and our clinical team will be available to answer any queries or concerns. Share all results with your healthcare provider for guidance on the next steps.

Check out our Heart Health knowledge hub for the insights you need to stay on top of your heart health.


  1. Ncbi.nlm.nih.gov
  2. Ncbi.nlm.nih.gov
  3. Thyroid.org
  4. Bhf.org.uk
  5. Ascopubs.org
  6. Ncbi.nlm.nih.gov

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