Cholesterol Explained: How to Read Your Cholesterol Test (LDL, HDL, Triglycerides)

March 2026

This article is for educational purposes only and does not provide medical advice.

Cholesterol is one of the most misunderstood markers in modern health care. Some people panic over numbers that aren’t necessarily a problem. Others feel reassured when their results may deserve a closer look. And many people receive lab results without ever being taught how to interpret them.

Understanding cholesterol requires looking at the bigger picture: metabolism, hormones, genetics, digestion, and lifestyle all play a role.

In this article, we’ll break down what cholesterol is, what your lipid panel actually measures, and why context matters when evaluating your cardiovascular risk.

Why Cholesterol Matters

Cholesterol is not inherently harmful. In fact, it is an essential molecule in the body.

Your body uses cholesterol to:

  • Build cell membranes

  • Produce hormones such as estrogen, testosterone, and cortisol

  • Create vitamin D

  • Produce bile acids that help digest fats

Most cholesterol is produced internally. In fact, about 80 percent of the cholesterol in your body is made by the liver. Even the intestines play a role in producing cholesterol.

Cholesterol circulates through the bloodstream inside particles called lipoproteins, which transport fats to where they are needed in the body. Some of these particles play a role in plaque formation in arteries, which is why cholesterol levels are closely linked with cardiovascular disease risk.

Cardiovascular Disease and Cholesterol

Cardiovascular disease remains one of the leading causes of death in Canada. Cardiovascular disease, by definition, refers to conditions affecting the heart and blood vessels, such as heart attacks and strokes. One of the most common processes involved is atherosclerosis, where plaque gradually builds up inside the arteries. Over time, this plaque can narrow blood vessels or rupture, which may lead to serious cardiovascular events.

Research has shown that higher concentrations of certain cholesterol-containing particles over long periods of time increase the likelihood of plaque development. This concept is sometimes referred to as “cholesterol years” — the cumulative exposure to these particles over time.

Understanding A Cholesterol Panel

A standard cholesterol test (often called a lipid panel) measures several markers that provide information about how cholesterol is moving through your body.

Common components include:

  • Triglycerides. Triglycerides are a type of fat in the blood that often reflect metabolic health and dietary patterns.

  • Total cholesterol. This is the overall amount of cholesterol detected in your blood.

  • HDL cholesterol. Often referred to as “good cholesterol,” HDL helps transport cholesterol back to the liver for removal from the body.

  • LDL cholesterol. LDL is commonly called “bad cholesterol” because it can contribute to plaque formation in the arteries.

  • Non-HDL cholesterol. This represents all cholesterol particles that may contribute to plaque formation.

  • Cholesterol/HDL Ratio. This ratio compares total cholesterol to HDL and is sometimes used to estimate cardiovascular risk (although it may also overestimate risk when HDL is above 2.0 nmol/L)

Clinicians look at the whole lipid profile as well as other health factors in order to understand someone’s cardiovascular disease risk.

Check out my YouTube video on cholesterol below, which reviews a lipid panel in detail starting at the 7:48 timestamp:

 
 

How Cardiovascular Risk Is Estimated

Healthcare providers typically estimate cardiovascular risk using tools such as the Framingham Risk Score, which calculates the likelihood of experiencing a cardiovascular event within the next 10 years.

This calculator uses several inputs, including:

  • Age

  • Sex

  • Smoking status

  • Blood pressure

  • Certain cholesterol values

Based on the result, individuals may be categorized into low, intermediate, or high risk groups.

More recently, another marker called lipoprotein(a) (Lp(a)) has gained attention because it reflects genetic risk for cardiovascular disease. Elevated levels are present in about 20% of the population and can significantly influence overall risk assessment. More advanced calculators will include inputs used in the Framingham Risk Score calculation, plus someone’s Lp(a) number.

A Common Misconception About “Good” HDL Cholesterol

Many people assume that higher HDL (“good cholesterol”) is always better. However, research now suggests that this relationship may be more complex. While very low HDL is associated with increased cardiovascular risk, extremely high HDL levels may not necessarily provide additional protection.

This highlights an important point: individual cholesterol markers should always be interpreted within the broader health context.

Why Cholesterol Levels Can Rise

Elevated cholesterol is not always caused by poor diet or lifestyle. Several health factors may influence cholesterol levels, including:

  • Hormonal changes, such as perimenopause

  • Insulin resistance and metabolic conditions

  • Polycystic ovary syndrome (PCOS)

  • Hypothyroidism

  • Chronic kidney disease

  • Liver disease

  • Genetic factors

For example, declining estrogen during perimenopause can influence cholesterol metabolism, which partly explains why cardiovascular risk increases in women after midlife.

Lifestyle and Cholesterol

A variety of lifestyle factors influence cholesterol levels and overall metabolic health. Research suggests that certain dietary patterns, particularly those emphasizing whole foods and fibre, will support healthier cholesterol levels. Specifically, the PREDIMED trial on the Mediterranean Diet demonstrated an approximately30 percent reduction in major cardiovascular events.

Fibre intake also plays an imperative role by influencing cholesterol metabolism through interactions with bile acids during digestion. Many people, however, consume less than the recommended daily fibre amount.

Physical activity is another factor linked to improvements in cholesterol markers. Current Canadian guidelines recommend regular aerobic activity combined with resistance training for overall cardiovascular health.

The Role of Genetics

Genetics greatly influence how individuals respond to dietary fat and cholesterol. Some people are hyper-absorbers of saturated fat, meaning their bodies absorb more saturated fat from food than average. Certain genetic variants, such as those related to the APOE gene, may affect how cholesterol is processed in the body.

This is one reason why two people following the same diet and lifestyle may have very different cholesterol results.

Why Interpreting Cholesterol Is Nuanced

Cholesterol results are rarely as simple as “good” or “bad.” Evaluating cardiovascular risk often involves considering multiple factors together, including:

  • Lipid panel markers

  • Genetics

  • Blood pressure

  • Smoking status

  • Inflammation markers, including C-reactive protein (CRP)

  • Coronary artery calcium score

  • Lipoprotein(a) and Apolipoprotein B values

  • Metabolic health

  • Family history

  • Other underlying health conditions, such as type 2 diabetes, chronic kidney disease, and liver disease

Because of this complexity, interpreting cholesterol results often requires looking beyond a single number.

The Bottom Line

Cholesterol is an essential part of human physiology, but the way it behaves in the body is influenced by many variables. Understanding your numbers involves more than simply looking at whether a lab value is flagged high or low. It requires considering the broader context of metabolic health, genetics, hormones, and lifestyle. Learning how these factors interact can help people make more informed decisions about their long-term cardiovascular health.

Dr. Dominique Vanier is a naturopathic doctor in the Oakville-Burlington region in Ontario. As a regulated health provider, she is registered to see patients in Ontario both virtually (online) and in person.

References:

  • Estruch, R., Ros, E., Salas-Salvadó, J., Covas, M. I., Corella, D., Arós, F., Gómez-Gracia, E., Ruiz-Gutiérrez, V., Fiol, M., Lapetra, J., Lamuela-Raventos, R. M., Serra-Majem, L., Pintó, X., Basora, J., Muñoz, M. A., Sorlí, J. V., Martínez, J. A., Fitó, M., Gea, A., Hernán, M. A., … PREDIMED Study Investigators (2018). Primary Prevention of Cardiovascular Disease with a Mediterranean Diet Supplemented with Extra-Virgin Olive Oil or Nuts. The New England journal of medicine, 378(25), e34. https://doi.org/10.1056/NEJMoa1800389

  • Framingham Risk Score: https://ccs.ca/wp-content/uploads/2020/12/FRS_eng_2017_fnl1.pdf

  • Lp(a) Clinical Guideance: https://www.lpaclinicalguidance.com/

  • Ko, D. T., Alter, D. A., Guo, H., Koh, M., Lau, G., Austin, P. C., Booth, G. L., Hogg, W., Jackevicius, C. A., Lee, D. S., Wijeysundera, H. C., Wilkins, J. T., & Tu, J. V. (2016). High-Density Lipoprotein Cholesterol and Cause-Specific Mortality in Individuals Without Previous Cardiovascular Conditions: The CANHEART Study. Journal of the American College of Cardiology, 68(19), 2073–2083. https://doi.org/10.1016/j.jacc.2016.08.038