Cholesterol/HDL ratio

The cholesterol/HDL ratio is a calculation: your total cholesterol divided by your HDL cholesterol, the so-called 'good' cholesterol. A result below 5 is considered favorable in Dutch laboratories. The higher the number, the more cholesterol is circulating in proportion that can contribute to atherosclerosis, and the greater the risk of cardiovascular disease may be. The ratio is a tool to summarize your cholesterol in a single number, not a diagnosis in itself.

Reference values

• Favorable: below 5.0. The ratio between total cholesterol and HDL cholesterol is balanced
• Elevated: 5.0 or higher. There is relatively little HDL cholesterol relative to the total; the further above 5, the more unfavorable
• Unit: The ratio has no unit, because both values ​​are measured in mmol/L and are divided against each other.

Example: a total cholesterol of 5.2 mmol/L and an HDL cholesterol of 1.3 mmol/L gives a ratio of 4.0.

What is the cholesterol/HDL ratio?

The cholesterol/HDL ratio shows in a single number how your total cholesterol relates to the part that has a protective effect. It is not a separate substance in your blood, but a calculation based on two values ​​that are already measured during a standard cholesterol test.

Cholesterol is a fatty substance that your body needs, for example, for the building of cells and the production of hormones. Total cholesterol is the sum of all types of cholesterol in your blood. HDL cholesterol is one of those types. It is known as 'good' cholesterol because it actually removes excess cholesterol.

As a result, two people with exactly the same total cholesterol can have a very different risk profile. Those with high HDL cholesterol end up with a low ratio. Those with low HDL cholesterol end up with a higher ratio for the same total.

How does it work in the body?

Cholesterol does not dissolve in blood. It is therefore transported in small packets of protein and fat, the lipoproteins. LDL packets carry cholesterol from the liver to the rest of the body. If there is too much of it in the blood, cholesterol can attach itself to the vessel wall. There it contributes to atherosclerosis: the vessels become stiffer and narrower.

HDL packets do the opposite. They absorb excess cholesterol from the tissue and the vessel wall and return it to the liver, which breaks it down or excretes it via the bile. The ratio balances these two forces against each other: the total (of which LDL is the largest part) versus the clearance capacity of HDL.

Why is the cholesterol/HDL ratio tested?

The ratio is determined to see at a glance whether your cholesterol balance is favorable or unfavorable. Because the calculation follows from a standard cholesterol test, it requires no extra blood or extra measurement.

For a long time, Dutch general practitioners used this ratio to estimate the risk of cardiovascular disease. This has changed in the current Dutch guideline for cardiovascular risk management. Non-HDL cholesterol is now used for that risk assessment: total cholesterol minus HDL cholesterol. For treatment decisions, the general practitioner primarily looks at LDL cholesterol.

The ratio remains a useful overview figure. Many laboratories still report it as standard, and it helps you understand your own results and track them over time. For example, to see if more exercise or a different diet improves your cholesterol balance. Therefore, always view the ratio together with your individual cholesterol values, and not as the sole measure.

Symptoms associated with an abnormal value

An unfavorable cholesterol/HDL ratio itself causes no symptoms. You do not notice anything from high cholesterol or low HDL. That is why it is often only discovered during a blood test.

Symptoms only arise when atherosclerosis leads to problems after years. Possible signs of this are:

• Pain or a feeling of pressure in the chest during exertion
• Shortness of breath during exertion that previously caused no difficulty
• Pain in the calves when walking, which disappears when you stand still
• Sudden loss of function, such as a crooked mouth, loss of strength in an arm, or difficulty speaking

These symptoms can also have other causes and say nothing about your ratio in itself. If you experience sudden loss of function or chest pain that does not go away, call 112 immediately. If you have any doubts about your results or other symptoms, your GP is the first point of contact.

What influences the value?

The ratio changes if total cholesterol, HDL cholesterol, or both change. A number of factors play a role in this.

Fasting: for total cholesterol and HDL cholesterol, fasting is usually not necessary. A meal hardly changes these two values.

Lifestyle: smoking lowers HDL cholesterol and makes the ratio less favorable. Regular exercise can slightly increase HDL cholesterol. A diet high in saturated fat increases total cholesterol. Being overweight, especially around the abdomen, is associated with lower HDL.

Heredity: in some people, cholesterol is high due to genetic predisposition, even with a healthy lifestyle. If cardiovascular disease runs in your family at a young age, it is relevant to discuss this with your GP.

Age and gender: Cholesterol often increases with age. On average, women have higher HDL cholesterol than men before menopause; after menopause, total cholesterol increases in many women.

Medication and conditions: Cholesterol-lowering drugs such as statins lower total cholesterol and, consequently, usually the ratio. An underactive thyroid, diabetes, and some kidney and liver conditions can also affect cholesterol levels.

A temporary dip: During or shortly after an acute illness, such as a severe infection, cholesterol levels may temporarily deviate. A repeat measurement at a quiet moment will then provide a more reliable picture.