Cholesterol: Crucial to Maintain Heart Health

Cholesterol is a fatty chemical that your liver produces. Your body manufactures all of the cholesterol need to operate. However, certain foods contain cholesterol.

According to the Centres for Disease Control and Prevention (CDC), having too much of the poor form of cholesterol, known as low-density lipoprotein (LDL), may increase your risk of certain health problems.

View of a blood vessel with blockage. Credit: unsplash

How is cholesterol measured?

To determine the total quantity of cholesterol in your blood, a healthcare practitioner will perform a lipid panel blood test. This is known as total cholesterol, and it consists of three lipids:

1. Low-density lipoproteins (LDLs) transport cholesterol throughout the system. LDL is known as “bad” cholesterol because excessive levels can build plaques in your blood vessels, increasing your risk of heart disease.
2. High-density lipoproteins (HDLs) protect against heart disease. HDL is known as “good” cholesterol because it transports cholesterol back to the liver, where it is eliminated from the body.
3. Triglycerides are another form of fat that can accumulate in the body. These are the “building blocks” of cholesterol. High levels of triglycerides and low levels of HDL increase the risk of stroke (paralysis) and heart attack¹.

How normal levels of Cholesterol maintain the heart health?

Cholesterol may accumulate in the walls of arteries, causing plaques. When these plaques collect, the arteries constrict and stiffen, resulting in a serious illness known as atherosclerosis. Normal cholesterol levels assist in avoiding the excessive formation of cholesterol plaques, lowering the risk of atherosclerosis.

Ference et al. published a study in 2017, which discussed how genetic studies have provided strong evidence supporting cholesterol’s causal role in atherosclerosis development. The study emphasised the need of maintaining normal cholesterol levels to avoid atherosclerosis and consequent cardiovascular problems.

Atherosclerosis can develop to coronary artery disease (CAD), which is a disorder in which the arteries that carry blood to the heart muscle thin or obstruct. This lowers blood supply to the heart, raising the risk of chest discomfort (angina), heart attack, and other cardiovascular issues. Maintaining normal cholesterol levels reduces the chance of getting CAD.

MESA (Multi-Ethnic Study of Atherosclerosis) published a prospective cohort study in 2018. The study “Association of Coronary Artery Calcium with Subsequent Incidence of Coronary Heart Disease: The Multi-Ethnic Study of Atherosclerosis (MESA)” discovered a significant relationship between coronary artery calcium, a marker of atherosclerosis, and the incidence of coronary heart disease. This highlights the significance of avoiding atherosclerosis by maintaining normal cholesterol levels.

Cholesterol can impede blood vessel function, reducing their capacity to expand and contract appropriately. Normal cholesterol levels assist blood arteries keep their suppleness and function, allowing for efficient blood flow throughout the body, including to the heart muscle. A study examined how cholesterol might affect endothelial function, contributing to the development of atherosclerosis. The study emphasised the need of sustaining blood vessel function by maintaining normal cholesterol levels in order to avoid endothelial dysfunction and consequent cardiovascular problems.

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Atherosclerosis can also damage arteries outside the heart, resulting in disorders such peripheral arterial disease (PAD). PAD typically affects the arteries that provide blood to the legs, resulting in symptoms such as leg discomfort, cramping, and poor wound healing. Keeping cholesterol levels under control minimises the chance of getting PAD.

A study published in Current Cardiology Reports, “Dyslipidemia Profiles in Patients with Peripheral Artery Disease” by Aaron W. Aday, et al. The results in the study emphasise the important lipid and apolipoprotein are the determinants of PAD.

Which type of fat is associated with negative effects on cholesterol and heart health?

Saturated fat as well as trans-fat are the type of fat that have the strongest link to high cholesterol and poor heart health.

1. Effect of saturated fat on cholesterol levels:

Mensink et al. published a meta-analysis in the American Journal of Clinical Nutrition in 2010, pooling data from 60 controlled trials and concluding that saturated fat consumption significantly increased levels of both LDL cholesterol and total cholesterol, both of which are associated with an increased risk of cardiovascular disease.
Saturated fats boost LDL cholesterol, sometimes known as “bad” cholesterol, which can contribute to the development of atherosclerosis and cardiovascular disease.

2. Effect of trans fatty acid on cholesterol levels:

Brouwer IA, et al. evaluated the literature and assessed the effects of bovine (cow) trans fatty acids and conjugated trans linoleic acid (CLA) on blood lipoproteins, comparing them to industrial trans fatty acids.

This review is the first to compare the effects of bovine trans fatty acids and CLA to those of industrial trans fatty acids on blood lipoproteins in humans. The findings reveal that all three kinds of trans fatty acids increase the LDL to HDL ratio, and therefore the risk of coronary heart disease.

Reference:

1. Susan M. Hageman; Saurabh Sharma. Low HDL Cholesterol

National Library of medicine, StatPearls Publishing; 2024 Jan.

• Brian A Ference, et al.

Low-density lipoproteins cause atherosclerotic cardiovascular disease. 1. Evidence from genetic, epidemiologic, and clinical studies. A consensus statement from the European Atherosclerosis Society Consensus Panel. Eur Heart J 2017 Aug 21;38(32):2459-2472.

• Matthew J Budoff, et al.

Ten-year association of coronary artery calcium with atherosclerotic cardiovascular disease (ASCVD) events: the multi-ethnic study of atherosclerosis (MESA).

• Yvonne Alexander, et al.

Endothelial function in cardiovascular medicine: a consensus paper of the European Society of Cardiology Working Groups on Atherosclerosis and Vascular Biology, Aorta and Peripheral Vascular Diseases, Coronary Pathophysiology and Microcirculation, and Thrombosis. Cardiovasc Res. 2021 Jan 1; 117(1): 29–42.

• Dyslipidemia Profiles in Patients with Peripheral Artery Disease

Aaron W. Aday, MD, MSc1 and Brendan M. Everett, MD, MPH2, Curr Cardiol Rep. 2019 Apr 22; 21(6): 42.

• Mensink RP, Zock PL, Kester AD, Katan MB, The effect of saturated fat on LDL-cholesterol: a review of recent evidence. American Journal of Clinical Nutrition Year: 2003 Volume: 70 Issue: 6 Pages: 1001-1008.

• Ingeborg A. Brouwer, Anne J. Wanders, Martijn B. Katan, Published: March 2, 2010

Effect of Animal and Industrial Trans Fatty Acids on HDL and LDL Cholesterol Levels in Humans – A Quantitative Review. https://doi.org/10.1371/journal.pone.0009434.