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Good Cholesterol vs. Bad Cholesterol
Updated on November 14, 2023
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Good Cholesterol vs. Bad Cholesterol
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Cholesterol often gets a bad rep because it has been linked with health conditions like heart disease. They aren’t all bad. Your body needs cholesterol — the good kind.

A healthy amount of cholesterol helps your body with functions, such as:

  • Digestion
  • Hormone secretion
  • Vitamin D production

Your liver makes sufficient cholesterol to support these processes. 

However, the liver isn’t the only source of cholesterol. Cholesterol (dietary) comes from food like meat and dairy. It is how your diet affects your cholesterol levels. 

Excess cholesterol from foods may lead to high cholesterol levels. Besides high blood pressure and smoking, high blood cholesterol is one of the leading risk factors for heart disease.

Good Cholesterol vs. Bad Cholesterol 2

What Is Cholesterol 

Cholesterol or blood cholesterol is a waxy, whitish-yellow, fat-like substance in your cell membranes. 

Cholesterol is oil-based, so it doesn’t mix with blood. Instead, your body packages cholesterol and other fats into spherical particles covered with proteins. These are called lipoproteins and they transport cholesterol.1

Cholesterol helps maintain the wholeness and fluidity of the cell membranes by holding them. It’s also essential in other body functions, like:2

  • Helping your liver produce bile, which is a kind of digestive fluid
  • Supporting the production of hormones, including estrogen, testosterone, and cortisol
  • Assisting with the body’s production of vitamin D

The liver mainly supplies the amount of cholesterol your body needs. The rest of the cholesterol in your bloodstream is from foods you eat, especially animal-source foods. 

Meat, poultry, and dairy have dietary cholesterol. These foods are also high in saturated and trans fats. These types of fats trigger your liver to produce more than its normal amount of cholesterol.  

This can make some people's cholesterol levels go from normal to unhealthy.

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What Are HDL And LDL Cholesterol

Cholesterol has two main types:

  • High-density lipoprotein (HDL) or the good cholesterol
  • Low-density lipoprotein (LDL) or the bad cholesterol

HDL (high-density lipoprotein) cholesterol

HDL, or the “good” cholesterol, gathers excess cholesterol. It collects cholesterol from the bloodstream, low-density lipoproteins, and arterial walls. Afterward, HDL carries them back to your liver. 

The liver breaks cholesterol down, so the body can dispose of them before they build up in the arteries. In a way, HDL help lower your overall cholesterol levels. 

They can also reduce your risk for heart disease. Studies link a higher HDL level to a lower heart attack or stroke incidence.3

LDL (low-density lipoprotein) cholesterol

Health experts often call LDL “bad” cholesterol. Too much LDL contributes to fatty build-ups or plaques in the blood vessel and artery walls. The plaques can cause the narrowing or hardening of blood vessels or arteries. 

The plaque formation can reduce the blood flow, which increases your risk of heart diseases like:4

  • Heart attack
  • Stroke
  • Peripheral artery disease (PAD)

Cholesterols — 3Cs

When it comes to regulating your cholesterol level for good heart health, always remember to follow the 3Cs:

  • Check — Have your cholesterol levels checked. Doctors use your cholesterol numbers to assess your risk.
  • Change — Make necessary changes to your diet and lifestyle to avoid too much cholesterol.
  • Control — Learn to control your cholesterol levels from your doctor or healthcare provider.

What Are The Ideal Ranges Of HDL and LDL Levels

A blood test called a lipoprotein panel measures the amount of cholesterol circulating in your blood. A cholesterol test checks your cholesterol number and reports your:5

  • Total blood cholesterol — The sum of your total cholesterol. It includes your HDL, LDL, and 20% of your total triglycerides 
  • Triglycerides — A common type of fat that the body uses for energy.
  • Low-density lipoprotein (LDL) — “Bad” cholesterol.
  • High-density lipoprotein (HDL) — ”Good” cholesterol

Your cholesterol numbers are indicated in miligrams per deciliter or mg/dl. Here’s a chart that shows the ideal range of total cholesterol, HDL, and LDL cholesterol.

Cholesterol Levels

What Causes High LDL cholesterol

Several factors can increase your risk of having a high LDL level.

Unhealthy food choices

Consuming too many foods that are high in saturated or trans fats can increase your LDL cholesterol. The following foods have high levels of saturated and trans fats:

  • Fatty cuts of meat
  • Full-fat dairy
  • Packaged snacks or desserts
  • Processed foods 

The American Heart Association sets a limit for saturated fat intake. They should only amount to five to six percent of your daily calories.6

Lack of physical activity or exercise 

Not having enough exercise or physical activity can contribute to a high cholesterol level. Studies show that physical activity and exercise increases LDL level while lowering HDL.10 

Exercise encourages the release of the enzymes that help move the LDL from the bloodstream to the liver.11,12 


Obesity is defined by a body mass index or BMI greater than 30. Doctors use BMI to assess your body fats.7

According to the AHA, anyone can have a high cholesterol level regardless of weight. But people with high BMI are at a greater risk.8 

Studies link a high BMI to increased LDL and reduced HDL. It suggests that people with obesity have more elevated bad cholesterol than good cholesterol.9

Changes in the HDL and LDL ratio result in higher cholesterol circulating in the blood. HDL is known to help dispose of LDL before they build up in the arteries and blood vessels. 

Cigarette Smoking

Smoking makes your LDL cholesterol more adhesive, and they end up clinging to your arterial walls. The plaque buildup can clog your arteries and increase your risk for heart attack and stroke.13

Smoking also lowers the enzymes needed to remove the LDL or bad cholesterol from your artery walls.14  


When you consume alcohol, your body breaks it down. Then, it's rebuilt into cholesterol and triglycerides in the liver. High triglyceride levels can cause fat buildup in the liver.15 


High levels of unhealthy cholesterol can affect anyone, even young children. But, it occurs more commonly in people over 40. 

Aging affects your liver’s ability to excrete LDL cholesterol from the body.16

What To Do If You Have High LDL

Ideally, your LDL level should stay below 70 mg/dl. If your blood test shows otherwise, a healthcare specialist can best guide you on lowering your LDL levels. 

Some of the things that can help are:

  • Avoiding foods that are high in dietary cholesterol, saturated fats, and high calories  
  • Exercising
  • Maintaining a healthy weight
  • Quitting smoking

How to Improve Your HDL

Changes in your diet, especially with your fat intake, can help boost your HDL cholesterol. 

Healthy fat sources that help increase your HDL and lower your LDL contain:17

1. Omega-3 fatty acids — Essential fats your body doesn’t produce. You can only get them from the food you eat. The best sources of omega-3 fatty acids are fish and plant-based foods like:

  • Salmon
  • Mackerel 
  • Herrings
  • Sardines
  • Flax seeds
  • Chia seeds
  • Walnuts

2. Monounsaturated fats — unlike saturated fat, they typically stay liquid at room temperature. The best sources of these fats are plant oils and foods like:

  • Extra-virgin olive oil
  • Peanut oil
  • Canola oil
  • Sesame oil
  • Avocados
  • Peanut butter
  • Almonds
  • Cashews
  • Peanuts
  • Pistachios
  • Olives

3. Polyunsaturated fats — also stay in liquid form when exposed to room temperature. The best sources of polyunsaturated fats include:

  • Corn oil
  • Oil-based salad dressings
  • Pumpkin seeds
  • Sunflower seeds
  • Soybean oil

Other Ways To Boost Your HDL

Besides switching to healthier food choices, lifestyle changes boost your HDL cholesterol. As you adjust your diet, try including these habits to optimize your heart health:

  • Exercise for at least 150 minutes a week
  • Quit cigarette smoking
  • Minimize your alcohol consumption to less than 14 units of alcohol per week15
  • Stay within the ideal range of weight

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Updated on November 14, 2023
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17 sources cited
Updated on November 14, 2023
  1. Cholesterol.” Harvard T.H. Chan School of Public Health.
  2. New Insights into Cholesterol Functions: A Friend or an Enemy?” National Center for Biotechnology Information. 
  3. HDL Cholesterol and Stroke Risk: The Multi-Ethnic Study of Atherosclerosis.” National Center for Biotechnology Information.
  4. HDL (Good), LDL (Bad) Cholesterol and Triglycerides.” American Heart Association.
  5. Cholesterol Numbers and What They Mean.” Cleveland Clinic.
  6. Saturated Fat.” American Heart Association.
  7. Defining Adult Overweight & Obesity.” Centers for Disease Control and Prevention.
  8. My Cholesterol Guide: Taken Action. Live Healthy!” American Heart Association.
  9. Dyslipidemia in Obesity: Mechanisms and Potential Targets.” National Center for Biotechnology Information.
  10. Differential Effects of Aerobic Exercise, Resistance Training and Combined Exercise Modalities on Cholesterol and the Lipid Profile: Review, Synthesis and Recommendations.” Sports Medicine.
  11. Differential Effects of Aerobic Exercise, Resistance Training and Combined Exercise Modalities on Cholesterol and the Lipid Profile: Review, Synthesis and Recommendations.” Sports Medicine.
  12. The effects of exercise training on lipid metabolism and coronary heart disease.” American Journal of Physiology.
  13. Smoking.” Heart U.K.
  14. Effects of cigarette smoking on HDL quantity and function: implications for atherosclerosis.” National Center for Biotechnology Information.
  15. Alcohol.” Heart U.K.
  16. High cholesterol.” Mayo Clinic.
Cristine Santander
Cristine Santander
Content Contributor
Cristine Santander is a content writer for KnowYourDNA. She has a B.S. in Psychology and enjoys writing about health and wellness.
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