Understanding Cholesterol to Better Control It

In Canada, cardiovascular disease is the second leading cause of death after cancer. High cholesterol is one of the risk factors for cardiovascular events that can be controlled. Therefore, it is important to understand the role of cholesterol and what can be done to reduce high blood cholesterol levels.

What is cholesterol?

Cholesterol is a fatty substance produced by the liver. It plays several key roles in the body, including the production of hormones (e.g., estrogen, testosterone), vitamin D, and bile, an important substance for fat digestion and nutrient absorption.

In order for cholesterol to circulate in the blood, it must attach itself to transport proteins to form what is known as a lipoprotein. The two main lipoproteins are:

• low-density lipoprotein (LDL) cholesterol and
• high-density lipoprotein (HDL) cholesterol.

LDL-cholesterol is transported from the liver to the cells and is sometimes called "bad” cholesterol. HDL-cholesterol is sometimes called "good" cholesterol because it helps in the removal of excess cholesterol by carrying it out of the cells.

What are the consequences of excess cholesterol in the blood?

When too much LDL cholesterol is present in the blood, it can settle on the walls of blood vessels and form deposits called plaque.

Over time, if the level of LDL-cholesterol in the blood remains too high, this plaque will continue to grow, gradually reducing the space available for blood to pass through. It is possible to have plaque in more than one artery at a time.

Plaque can also break into pieces and form clots that can completely block the passage of blood. If the blockage occurs in the heart, it causes a heart attack. If it occurs in the brain, it causes a stroke.

Why do some people have too much LDL-cholesterol?

Several factors increase the risk of high LDL-cholesterol, such as:

• Poor diet, especially high in trans fats and/or saturated fats
• Sedentary lifestyle
• Being overweight
• Chronic stress
• Smoking
• Aging

Most LDL-cholesterol (about 80%) is produced by the liver, regardless of our lifestyle. In some families, high cholesterol levels are caused by an inherited disease.

What are the symptoms of high cholesterol levels in the blood?

LDL-cholesterol itself does not cause any symptoms. It is usually discovered to be too high when blood tests are done as part of a check-up, or when the person has a cardiovascular event such as a heart attack or stroke.

What can be done to lower cholesterol levels?

Lifestyle modifications are essential for managing high cholesterol. Here are some recommendations to improve your lifestyle.

1. Eat a healthy diet
2. Engage in regular physical activity
3. Achieve and maintain a healthy weight
4. Manage stress
5. Stop smoking

1. Eat a healthy diet

The typical North American diet is often high in animal products (e.g., red meat, processed meats, high-fat dairy products) and processed foods that may contain cholesterol, but most often saturated or trans fats. Because these types of fats increase the liver's production of LDL-cholesterol, you should limit the amount you eat.

Foods that are high in cholesterol but low in saturated fat (such as egg yolks, some seafood, and organ meats) can be eaten in moderation.

To make lasting improvements to your diet, make incremental changes. Start by removing processed foods from your diet. Try to cook your own meals to ensure they contain healthy ingredients, such as

• Plenty of fruits and vegetables
• High-fiber foods (e.g., barley, oats, quinoa)
• Plant-based proteins, such as beans, lentils, tofu, or nuts
• Small amounts of lean meats

If you need help improving your diet, talk to a registered dietitian. 

2. Engage in regular physical activity

Studies have shown that people who are physically active have higher levels of HDL-cholesterol, the "good" cholesterol, than sedentary people. Regular physical activity also improves both physical and mental health, and contributes to weight loss and stress reduction. 

You do not have to become a top-level athlete! It is recommended that you exercise on a regular basis, for at least 30 minutes a day and at least five times a week. Choose an activity that fits easily into your routine, such as walking. If you're having trouble getting motivated, join a friend, colleague, or club.

If you have a chronic health condition, talk to your health care team to find out if there are any restrictions that you should be aware of.

3. Achieve and maintain a healthy weight

Obesity is associated with higher levels of LDL-cholesterol and lower levels of HDL-cholesterol. Improving your diet and/or physical activity may help you lose weight. For medical treatment of obesity, you should consult a healthcare professional.

4. Manage stress

Studies have shown that people who experience prolonged periods of stress have higher levels of LDL-cholesterol.
Learn different techniques to reduce stress, such as meditation, mindfulness, breathing, or relaxation techniques.

Try to identify the sources of chronic stress in your life and see if you can reduce or eliminate them. This often isn't easy and may require you to question certain priorities, but making these important changes will benefit your overall health and quality of life.

5. Stop smoking

Smoking lowers HDL-cholesterol and increases the risk of cardiovascular disease. If you smoke, talk to your pharmacist. In most provinces, pharmacists can prescribe smoking cessation medication to help you quit for good. Do not hesitate to ask for advice.

When should pharmacological treatment be considered?

If you are not at high risk for a cardiovascular event (such as a heart attack or stroke), you will usually start with lifestyle changes before considering drug treatment. If LDL-cholesterol levels are still too high after a few months of lifestyle changes, drug treatment may be prescribed.

However, if your LDL-cholesterol is very high, or if you are at high risk for a cardiovascular event (for example, if you have had a heart attack or stroke, or if you have diabetes or chronic kidney disease), drug treatment should usually be started at the same time as lifestyle changes.

Several medicines can lower LDL-cholesterol. Your healthcare provider will prescribe the one that is best for you.

Your pharmacist, your ally to achieve your goals

If you have questions about cholesterol or cholesterol-lowering medicines, see your pharmacist. In addition to answering your questions, your pharmacist can help you make lifestyle changes and refer you to other professionals, such as a registered dietitian or kinesiologist, if needed.

In some provinces, pharmacists may offer a service to help you achieve your cholesterol reduction goals. Check with the staff at your local pharmacy for more information.