Let's Learn About Cholesterol

High cholesterol levels are associated with illnesses such as cardiovascular disease and type 2 diabetes. This has caused a negative stigma around consuming cholesterol, with many diets and health regimens focusing on specifically cutting out this molecule. Yet, it is present in and essential for animal cells; the body produces cholesterol to help regulate the functions of many organs. So, what is cholesterol and why is too much of it dangerous?

Foods with high levels of cholesterol (D'Angelo Friedman, 2025).

What is cholesterol?

Cholesterol is a lipophilic molecule: it combines with lipids and travels through the bloodstream in large molecules called lipoproteins. There are a few types of cholesterol which are classified by what type of lipoprotein they travel with. The most common of these are HDL and LDL cholesterol (what is known as good and bad cholesterol, respectively). HDL cholesterol is considered ‘good’ because it removes the ‘bad’ LDL cholesterol which, in excess, causes plaque build-ups in the arteries. It is important to note that both HDL and LDL cholesterol are necessary; cholesterol is a required for the synthesis of Vitamin D, sex and steroid hormones, and the production of bile in the liver. The liver produces 80% of the cholesterol needed to function, while the rest comes from food intake (What is Cholesterol?, 2025). Major cholesterol sources are foods with saturated fat (e.g. red meat) or trans-fat (packaged and fried foods) (Friedman, 2025). Every year there is increased processed and packaged food intake, leading to increased cholesterol levels. That’s why it is so important to have a balanced diet and avoid the dangers of too much cholesterol. 

HDL vs. LDL cholesterol impact on arteries ("What is Cholesterol", 2025).

Impact of cholesterol imbalances

The body naturally regulates cholesterol levels by slowing production when higher levels are present. This negative feedback has limits though, which can be reached when food intake spikes cholesterol levels. When a person has high cholesterol, excess lipids form plaque in the arteries (Alila Medical Media, 2018). This plaque can build up over the years, having seemingly no effect on health. When the arteries are significantly clogged or blocked, they stop working efficiently, putting strain on the heart. High cholesterol levels, over time, are associated with many illnesses, most notably cardiovascular disease.

Key Takeaways

Cholesterol is vital for many bodily functions and is present in every cell of the body. Although it is necessary, too much of anything is bad for you. High cholesterol levels are common in the US, and dangerous as it leads to many illnesses. By making healthy food choices and getting regular screenings, people can manage their cholesterol and reduce their risk of heart disease.

References

1. Alila Medical Media (Director). (2018, May 1). Cholesterol Metabolism, LDL, HDL and other Lipoproteins, Animation [Video recording]. https://www.youtube.com/watch?v=9dghtf7Z7fw

2. Blood Cholesterol—What is Blood Cholesterol? (2024, April 17). National Heart, Lung, and Blood Institute. https://www.nhlbi.nih.gov/health/blood-cholesterol

3. D’Angelo Friedman, J. (2025, April 11). Foods To Eat & Avoid For High Cholesterol. HealthCentral. https://www.healthcentral.com/condition/high-cholesterol/high-cholesterol-foods

4. Huff, T., Boyd, B., & Jialal, I. (2025). Physiology, Cholesterol. In StatPearls. StatPearls Publishing. http://www.ncbi.nlm.nih.gov/books/NBK470561/

5. Hughes, A. (2025, May 10). Here’s what actually causes high cholesterol (and how to cut it). BBC Science Focus Magazine. https://www.sciencefocus.com/the-human-body/how-to-lower-cholesterol

6. LeWine, H. E. (2010, April 6). 11 Foods that Lower Cholesterol—Harvard Health Publishing. Harvard Health. https://www.health.harvard.edu/heart-health/11-foods-that-lower-cholesterol

7. What Is Cholesterol? (n.d.). Cleveland Clinic. Retrieved August 16, 2025, from https://my.clevelandclinic.org/health/articles/23922-what-is-cholesterol

8. HDL (Good), LDL (Bad) Cholesterol and Triglycerides. (2024, February 19). American Heart Association. https://www.heart.org/en/health-topics/cholesterol/hdl-good-ldl-bad-cholesterol-and-triglycerides

Thumbnail image: (Hughes, 2025)