Apolipoprotein B (ApoB) is a carrier protein that helps transport LDL cholesterol (also known as “bad” cholesterol) as well as other harmful fat molecules in the blood.
The body needs to transport cholesterol and other fatty molecules from the diet through the blood to where they are needed. The transport of fats in the blood is facilitated by various lipoproteins such as LDL and HDL, also known as “bad” and “good” cholesterol, respectively.
Apolipoprotein B is the main component in LDL, meaning that each LDL molecule has an ApoB protein attached to it. In HDL, it is instead apolipoprotein A1 (ApoA1) that is the main component.
The Apo proteins themselves help produce enzymes that break down fat molecules and also help bind to receptors on various cells to which the fat molecules are to be transported. By measuring the concentration of ApoB in the blood, one can therefore make an estimate of the amount of cholesterol in the bloodstream.
Both LDL and HDL are necessary for health and play important roles in the body, so calling LDL solely “bad” cholesterol is somewhat misleading. However, a high concentration of LDL, especially in relation to the amount of HDL, is strongly associated with an increased risk of cardiovascular disease.
ApoB is analyzed because its quantity and relationship to ApoA1 are risk markers for cardiovascular disease. Especially in overweight individuals, as well as those with diabetes and kidney diseases, levels may be unhealthy even if they are within the reference range. This is because all these conditions, in various ways, elevate cholesterol levels or make the body more sensitive to high cholesterol levels.
Overweight, metabolic syndrome, and type 2 diabetes, all of which negatively affect cholesterol levels, have become increasingly common. In these risk groups, the result from a traditional cholesterol test may be slightly elevated or normal, even though there is an increased risk of disease. In such situations, it is particularly beneficial to know the number and ratio between cholesterol-carrying proteins rather than just the total concentration.
Many are aware that a high cholesterol level increases the risk of future cardiovascular disease, but even levels within the normal range, where the ratio between LDL and HDL is high, have been shown to be detrimental to long-term health. The higher the levels of ApoB (measuring LDL) in relation to ApoA1 (measuring HDL), the greater the risk of cardiovascular disease.
A high total cholesterol level, and especially a high ratio between LDL and HDL, leads to increased atherosclerosis. Increased atherosclerosis can then cause a range of problems with the heart and blood vessels, increasing the risk of conditions such as heart failure, heart attack, and stroke.
An appropriate amount of LDL in relation to HDL, on the other hand, reduces the risk of cardiovascular disease, even when total cholesterol levels are higher. The balance between “bad” LDL and “good” HDL is simply more important than the individual levels of each value.
A high ratio between ApoB and ApoA1 (which measures the “good” HDL cholesterol) does not produce any direct symptoms but increases the risk of developing diseases over time. It may therefore be useful to examine one’s ApoB/ApoA1 ratio with a simple blood test to check the risk of developing cardiovascular disease.
The target value for ApoB in both men and women is less than 0.9 g/L, and its reference values are:
Reference values may vary depending on where the analysis is performed and which analysis method is used.
A high value indicates a higher risk of developing cardiovascular diseases such as heart attack, heart failure, and stroke. The high value may be due to both genetic factors and lifestyle. Lack of exercise, overweight, and a diet rich in saturated fat and fast carbohydrates all negatively affect cholesterol levels.
A low value is usually a good sign and is associated with good health in general.
Even if one’s level is within the reference range, however, a higher risk of cardiovascular disease may exist if the ratio between ApoB and ApoA1 is high.
A traditional cholesterol test measures the total level of cholesterol in the blood. But not only the total level, but also the relationship between the amount of LDL and HDL, affects the risk of developing cardiovascular disease.
Direct HDL and LDL analyses differentiate ApoB-containing lipoproteins such as LDL from other lipoproteins such as ApoA1-containing HDL. The number of LDL and HDL particles can therefore be assessed with these tests. The measurement specifically determines the amount of the most important components in the different lipoproteins, namely ApoB and ApoA1.
The ApoB test measures the amount of all atherogenic lipoproteins and is often combined with an ApoA1 test, which measures HDL. Something atherogenic causes atherosclerosis or arterial disease.
The ApoB examination is suitable for assessing the risk of cardiovascular disease in individuals who want to know if there is a risk. It may be beneficial if you know that older relatives have suffered from cardiovascular disease, if you are overweight, suffer from diabetes, or if you are simply curious to examine and influence your own health.
Lifestyle can greatly affect blood fats and cholesterol levels. In general, healthy diet and exercise habits yield good values, while calorie- and fat-rich diets combined with inactivity result in poorer values. Therefore, good values can be achieved by maintaining good physical condition and consuming a healthy diet low in saturated fat.
It is also good to avoid excessive intake of fast carbohydrates, which means food with a high glycemic index. High ApoB levels are often associated with high levels of liver triglycerides. High liver triglycerides can be caused not only by a high fat intake but also by a diet with a high glycemic index. Fast carbohydrates, i.e., food with a high glycemic index, also raise ApoB levels. Therefore, it is important not to replace a high-fat diet with one containing many fast carbohydrates if you are trying to lower your cholesterol level.
Obesity and metabolic syndrome with accompanying insulin resistance can also raise ApoB levels. Therefore, losing weight if you are overweight can help lower your cholesterol level.
Vital laboratory package Man 50+ includes 36 values and provides you with a comprehensive overview of your health. Vital’s doctors have developed this laboratory package based on some of the most important values that affect age-related lifestyle diseases, as well as values that are interesting to monitor specifically for you as a man over 50 years old.
Vital laboratory package Woman 50+ includes 39 values and provides senior women with a broad overview of their health. Vital’s doctors have developed this laboratory package based on some of the most important values that affect age-related lifestyle diseases, as well as values that are interesting to monitor specifically for you as a woman over 50 years old.
Vital laboratory package Total Plus includes 37 values and is an even more comprehensive health check for those who seek a deeper insight into their body’s well-being and greater opportunities to make better choices to improve their health.
Apolipoprotein B (ApoB) is a carrier protein that helps transport LDL cholesterol, also known as bad cholesterol, as well as other harmful fat molecules in the blood.
Apolipoprotein A1 (ApoA1) is a carrier protein that helps transport HDL cholesterol (also known as good cholesterol) as well as other harmful fat molecules in the blood.
CRP or a high-sensitivity CRP test is usually carried out if an inflammatory disease is suspected.
The total cholesterol measurement shows the total cholesterol value in the blood.
Studies show that HDL cholesterol, or “good cholesterol”, is linked to better vascular health.
The LDL cholesterol level shows the amount of harmful cholesterol in the blood.
Article updated:
15 May 2024