HDL Cholesterol

What it is

HDL stands for High-Density Lipoprotein. Think of it as a tiny, helpful courier service in your bloodstream. Cholesterol itself is a fatty substance that your body needs to build healthy cells. However, cholesterol can't travel around in your blood on its own because blood is watery. So, it needs to be packaged into particles called lipoproteins.

There are different types of lipoproteins, and HDL is one of them. HDL particles are particularly good at picking up excess cholesterol from around your body, including from the walls of your arteries. They then transport this cholesterol back to the liver, where it can be processed and removed from the body. Because of this 'scavenging' role, HDL cholesterol is often referred to as 'good' cholesterol.

The amount of HDL cholesterol in your blood is measured in millimoles per litre (mmol/l). The reference range for HDL cholesterol in the UK is generally considered to be 1.55 mmol/l and above, though specific target levels can vary depending on individual health factors.

Why it matters

The primary reason HDL cholesterol is important is its protective role against heart disease. By removing excess cholesterol from artery walls, HDL helps to prevent the build-up of fatty plaques, a process known as atherosclerosis. This build-up can narrow the arteries, restricting blood flow and increasing the risk of heart attacks and strokes.

A higher level of HDL cholesterol is generally associated with a lower risk of cardiovascular disease. It's thought that the more efficient your HDL courier service is, the better your body is at keeping your arteries clear. Conversely, lower levels of HDL cholesterol may be linked to an increased risk of heart problems.

It's worth noting that while HDL cholesterol is important, it's just one piece of the puzzle when it comes to heart health. Your overall cholesterol profile, including LDL ('bad') cholesterol, triglycerides, and other risk factors like blood pressure, diet, and exercise, all play a part.

What can cause it to be high or low

Several factors can influence your HDL cholesterol levels.

Factors that may be associated with higher HDL cholesterol include:

• Genetics: Some people naturally have higher HDL levels due to their inherited genes.
• Regular physical activity: Moderate to vigorous exercise can often lead to an increase in HDL cholesterol.
• Weight management: Maintaining a healthy weight can be beneficial for HDL levels.
• Certain medications: Some medicines prescribed by your doctor can help to raise HDL cholesterol.

Factors that may be associated with lower HDL cholesterol include:

• Genetics: Again, inherited genes can sometimes lead to lower HDL levels.
• Sedentary lifestyle: Lack of regular physical activity is a common reason for lower HDL.
• Being overweight or obese: Excess body weight can negatively impact HDL levels.
• Smoking: Smoking is known to lower HDL cholesterol and damage blood vessels.
• Diet: A diet high in unhealthy fats, particularly trans fats and refined carbohydrates, can lower HDL.
• Certain medical conditions: Conditions such as type 2 diabetes, metabolic syndrome, and hypothyroidism can sometimes be associated with lower HDL.
• Age and sex: HDL levels can change with age, and there are often differences between men and women.

Lifestyle factors that may help

Making certain lifestyle changes can be a positive step towards optimising your HDL cholesterol levels and supporting your overall heart health. These are all areas you might wish to discuss with your GP.

• Regular Exercise: Engaging in regular aerobic exercise, such as brisk walking, jogging, swimming, or cycling, is often recommended. Aiming for at least 150 minutes of moderate-intensity activity per week is a common guideline.
• Healthy Diet: Focusing on a balanced diet rich in fruits, vegetables, whole grains, and lean proteins can be beneficial. Including sources of healthy fats, such as those found in olive oil, avocados, nuts, and seeds, may also be helpful. Limiting intake of processed foods, sugary drinks, and foods high in saturated and trans fats is often advised.
• Weight Management: If you are carrying excess weight, achieving and maintaining a healthier weight through diet and exercise can have a positive impact on your cholesterol levels.
• Giving Up Smoking: Smoking cessation is one of the most significant steps you can take for your cardiovascular health. It can help to improve HDL cholesterol levels and reduce overall risk.
• Moderate Alcohol Intake: If you drink alcohol, doing so in moderation is generally advised. Excessive alcohol consumption can have negative effects on health.

Questions to discuss with your GP

When you have your blood test results, it's always a good idea to have a conversation with your GP. Here are some questions you might consider asking:

• What does my HDL cholesterol level mean in the context of my overall health?
• Are my HDL levels considered optimal for me, taking into account my personal health history?
• What are the potential implications of my HDL level for my future heart health?
• Are there any specific lifestyle changes you would recommend for me to help improve my HDL cholesterol?
• Should I be considering any further tests or monitoring for my cholesterol levels?
• Are there any other factors in my blood test results that are particularly important to discuss?