What are apolipoproteins A1 and B?

Apolipoproteins are important biomarkers for assessing your risk of cardiovascular disease. Importantly, your ApoB:ApoA1 ratio can often give a more accurate picture of your risk compared with individual cholesterol results [1].

In this guide, we look at what your levels mean and how you can improve your results. 

• What are apolipoproteins?
• Assessing risk: apolipoproteins vs cholesterol
• Checking your apolipoprotein levels
• What is apolipoprotein A1 (ApoA1)
• What is apolipoprotein B (ApoB)
• What is the ApoB:ApoA1 ratio?

What are apolipoproteins?

Apolipoproteins are special proteins that help to transport fats (lipids), including cholesterol, around your body in the bloodstream. They are a crucial part of lipoproteins, which are particles that carry these fats. Examples of lipoproteins include low-density lipoproteins (LDL), high-density lipoproteins (HDL), and chylomicrons.

There are different types of apolipoproteins and they help to influence the structure of lipoproteins and metabolism of fats. We’ll mainly focus on apolipoprotein A1 and apolipoprotein B.

Why are apolipoproteins a better measure of cardiovascular risk than cholesterol?

Experts often consider apolipoprotein levels to be better measures of cardiovascular risk than individual cholesterol markers (like LDL). There are several reasons for this. 

Reasons apolipoproteins can give a better measure of cardiovascular risk:

• Particle number vs cholesterol content – ApoB gives a count of the number of LDL and other bad cholesterol particles rather than measuring the cholesterol content within these particles. Occasionally, the number of LDL particles doesn’t correlate with the amount of cholesterol within these particles. When this happens, most studies show that the number of LDL particles gives a better picture of risk [2]. 
• Includes all bad cholesterol – ApoB accounts for all lipoproteins that contribute to the build-up of fatty plaques in the arteries. For example, ApoB is also found in intermediate-density lipoproteins (IDLs) and other smaller, denser particles. Therefore, ApoB is less likely to underestimate your risk compared to an LDL cholesterol result.
• Consistency – ApoB levels are more consistent and less influenced by short-term dietary changes compared to LDL cholesterol levels. This makes them a more stable marker for assessing risk.

How can I check my apolipoprotein levels?

You can check your apolipoprotein levels from home with our Apolipoprotein Profile Blood Test. You can collect the sample yourself as a finger-prick test and post it back to us. Our doctors will then give you a full, personalised report on your test results.

Or, for a much more comprehensive health check into your long-term health and cardiovascular risk, we recommend our Optimal Health Blood Test.

What is apolipoprotein A1 (ApoA1)?

Apolipoprotein A1, or ApoA1, is a protein found in HDL cholesterol. HDL cholesterol is also known as good cholesterol because it helps carry excess cholesterol back to the liver, which removes it from your body. This helps prevent cholesterol from building up in the arteries, which contributes to heart attacks and strokes.

Therefore, higher levels of ApoA1 often equate to a lower cardiovascular risk.

What causes a low apolipoprotein A1 result?

A low ApoA1 level is often associated with low levels of HDL cholesterol. Therefore, things that boost your HDL level will often improve your ApoA1 level too.

Factors that may contribute to a lower ApoA1 level include: 

• Smoking
• Being overweight
• Lack of exercise
• Medications – such as water tablets (diuretics) and anabolic steroids
• Uncontrolled diabetes
• Hypoalphalipoproteinaemia – a rare genetic condition

How to increase your apolipoprotein A1 (ApoA1) level naturally

There are many ways you can increase your ApoA1 level to reduce your cardiovascular risk. Many of these tactics also help to lower your blood pressure and create a healthier balance of fats in your body.

Natural ways to increase your ApoA1 level include:

• Eating a healthy diet – a reduced intake of foods high in added sugars (such as pastries, sweets, and chocolate) is associated with higher ApoA1 levels [3]. The heart-healthy Mediterranean diet can also help increase your HDL cholesterol level [4]. 
• Being physically active – studies show that aerobic and resistance exercise may lead to increased ApoA1 levels [5,6].
• Quitting smoking – ApoA1 levels are higher in non-smokers than in smokers [7].
• Losing weight if you’re overweight – people with a lower body mass index (BMI) tend to have higher ApoA1 levels [3].

What is apolipoprotein B (ApoB)?

Apolipoprotein B, or ApoB, is found in low-density lipoprotein (LDL) cholesterol, also known as bad cholesterol. LDL cholesterol plays an important role in transporting cholesterol to the tissues and arteries. But too much LDL cholesterol can lead to the build-up of cholesterol in the artery walls (atherosclerosis). Atherosclerosis increases your risk of conditions like heart attacks and stroke.

ApoB is an important biomarker because each LDL particle contains one ApoB molecule. Your ApoB level therefore reflects the number of particles in the blood that can contribute to atherosclerosis, giving a better measure of your risk of cardiovascular disease than LDL cholesterol alone.

What causes a high ApoB result?

ApoB levels are usually, but not always, associated with LDL cholesterol levels. Therefore, many factors that increase LDL levels also impact ApoB. 

Factors that may contribute to raised ApoB levels include: 

• Obesity – a large study found that people with a high BMI were much more likely to have high ApoB levels [3].
• Smoking
• Diet – a diet high in saturated fats can increase ApoB levels. This includes foods like sausages, butter, cheese, biscuits, cakes, and cream [8].
• Diabetes – people with type 2 diabetes clear ApoB at a slower rate[9].
• Hypothyroidism – an underactive thyroid can impact your cholesterol levels as well as ApoB level [10,11].
• Genetic factors – inherited conditions like familial combined hyperlipidaemia can cause high cholesterol and ApoB levels.

How to lower your apolipoprotein B (ApoB) level naturally

There are many ways you can lower your ApoB level, from lifestyle changes to medications. 

Natural ways to reduce ApoB levels include:

• Losing weight if you’re overweight – the combined results of several studies showed that a 6-12% weight loss can cause significant reductions in ApoB levels [12].
• Following a Mediterranean diet – a Mediterranean diet not only increases ApoA1 levels but also reduces ApoB levels [4,13].
• Regular exercise – moderate-intensity exercise can help reduce ApoB levels [14,15]. The NHS advises at least 150 minutes of moderate-intensity exercise a week. 
• Increasing your sterol/stanol intake – increasing your intake of foods enriched with plant sterols/stanols reduces ApoB levels [16]. Examples include fortified yoghurts, fat spreads, and milk. 

Do statins lower ApoB?

Yes, statins decrease LDL cholesterol production in the liver and so reduce ApoB levels. They can be a very effective treatment alongside lifestyle changes.

     

What is the ApoB:ApoA1 ratio?

The ApoB:ApoA1 ratio gives an insight into your balance of apolipoproteins. A higher ratio indicating more ApoB relative to ApoA1, suggests a higher risk for heart disease. A high ratio has implications for your long-term health too because conditions like heart attacks and stroke can significantly impact longevity and the number of years spent in good health. 

Many experts believe the ApoB:ApoA1 ratio is a better measure of cardiovascular risk than traditional cholesterol measurements for the reasons mentioned above [1]. 

How to lower your ApoB:ApoA1 ratio naturally

Lowering your ApoB:ApoA1 ratio involves the same approach as lowering your ApoB level or increasing your ApoA1 level. 

Natural ways to reduce your ApoB:ApoA1 ratio include:

• Switching to a Mediterranean diet – the Mediterranean diet is renowned for its beneficial effect on cardiovascular health, including lowering ApoB:ApoA1 ratios. Vegans are also likely to have lower ApoB:A1 ratios [4,17]. 
• Increasing your omega-3 intake – people who include lots of omega-3 fatty acids in their diet are more likely to have lower ApoB:A1 ratios [17]. Omega-3 is found in oily fish, flax seed, and fish oil supplements. 
• Decrease your sugar intake – people who eat less added sugars tend to have healthier ApoB:ApoA1 ratios [17].
• Getting active – physical activity can both increase ApoA1 levels and reduce ApoB levels, significantly improving your ratio [18]. 
• Getting a good night’s sleep –some studies show that longer sleep duration is associated with a lower ApoB:ApoA1 ratio[19].

Summary

ApoA1 and ApoB are important biomarkers that provide deeper insights into your heart health. Maintaining a low ApoB:ApoA1 ratio is crucial for reducing the risk of conditions such as heart attacks and strokes, which can significantly influence your overall wellbeing and longevity.
 

References

1. Walldius G, Jungner I, Holme I, Aastveit AH, Kolar W, Steiner E. High apolipoprotein B, low apolipoprotein A-I, and improvement in the prediction of fatal myocardial infarction (AMORIS study): a prospective study. Lancet. 2001;358: 2026–2033. doi:10.1016/S0140-6736(01)07098-2
2. Attia P. Measuring cardiovascular disease risk and the importance of apoB. In: Peter Attia [Internet]. 22 Dec 2019 [cited 18 Dec 2023]. Available: https://peterattiamd.com/measuring-cardiovascular-disease-risk-and-the-importance-of-apob-part-1/
3. Frondelius K, Borg M, Ericson U, Borné Y, Melander O, Sonestedt E. Lifestyle and Dietary Determinants of Serum Apolipoprotein A1 and Apolipoprotein B Concentrations: Cross-Sectional Analyses within a Swedish Cohort of 24,984 Individuals. Nutrients. 2017;9: 211. doi:10.3390/nu9030211
4. Solá R, Fitó M, Estruch R, Salas-Salvadó J, Corella D, de La Torre R, et al. Effect of a traditional Mediterranean diet on apolipoproteins B, A-I, and their ratio: a randomized, controlled trial. Atherosclerosis. 2011;218: 174–180. doi:10.1016/j.atherosclerosis.2011.04.026
5. Yazdani R, Marefati H, Shahesmaeili A, Nakhaei S, Bagheri A, Dastoorpoor M. Effect of Aerobic Exercises on Serum Levels of Apolipoprotein A1 and Apolipoprotein B, and Their Ratio in Patients with Chronic Obstructive Pulmonary Disease. Tanaffos. 2018;17: 82–89.
6. Ahn N, Kim K. Dynamic Resistance Exercise Alters Blood ApoA-I Levels, Inflammatory Markers, and Metabolic Syndrome Markers in Elderly Women. Healthcare. 2022;10: 1982. doi:10.3390/healthcare10101982
7. Kauss AR, Antunes M, de La Bourdonnaye G, Pouly S, Hankins M, Heremans A, et al. Smoking and apolipoprotein levels: A meta-analysis of published data. Toxicol Rep. 2022;9: 1150–1171. doi:10.1016/j.toxrep.2022.05.009
8. Association of dietary nutrients with blood lipids and blood pressure in 18 countries: a cross-sectional analysis from the PURE study - The Lancet Diabetes & Endocrinology. [cited 19 Dec 2023]. Available: https://www.thelancet.com/journals/landia/article/PIIS2213-8587(17)30283-8/fulltext
9. Zhang P, Gao J, Pu C, Zhang Y. Apolipoprotein status in type 2 diabetes mellitus and its complications (Review). Molecular Medicine Reports. 2017;16: 9279–9286. doi:10.3892/mmr.2017.7831
10. Klausen IC, Nielsen FE, Hegedüs L, Gerdes LU, Charles P, Faergeman O. Treatment of hypothyroidism reduces low-density lipoproteins but not lipoprotein(a). Metabolism. 1992;41: 911–914. doi:10.1016/0026-0495(92)90176-B
11. Tiwari V, Kulshrestha M, Tripathi P. “Serum Apolipoprotein levels in hypothyroidism.” 2019;4: 483–487.
12. Dansinger ML, Williams PT, Superko HR, Schaefer EJ. Effects of weight change on apolipoprotein B-containing emerging atherosclerotic cardiovascular disease (ASCVD) risk factors. Lipids Health Dis. 2019;18: 154. doi:10.1186/s12944-019-1094-4
13. Bédard A, Riverin M, Dodin S, Corneau L, Lemieux S. Sex differences in the impact of the Mediterranean diet on cardiovascular risk profile. Br J Nutr. 2012;108: 1428–1434. doi:10.1017/S0007114511006969
14. Caro J, Navarro I, Romero P, Lorente RI, Priego MA, Martínez-Hervás S, et al. Metabolic effects of regular physical exercise in healthy population. Endocrinol Nutr. 2013;60: 167–172. doi:10.1016/j.endonu.2012.11.004
15. Stanton KM, Kienzle V, Dinnes DLM, Kotchetkov I, Jessup W, Kritharides L, et al. Moderate‐ and High‐Intensity Exercise Improves Lipoprotein Profile and Cholesterol Efflux Capacity in Healthy Young Men. Journal of the American Heart Association. 2022;11: e023386. doi:10.1161/JAHA.121.023386
16. Barkas F, Bathrellou E, Nomikos T, Panagiotakos D, Liberopoulos E, Kontogianni MD. Plant Sterols and Plant Stanols in Cholesterol Management and Cardiovascular Prevention. Nutrients. 2023;15: 2845. doi:10.3390/nu15132845
17. Nacarelli GS, Fasolino T, Davis S. Dietary, macronutrient, micronutrient, and nutrigenetic factors impacting cardiovascular risk markers apolipoprotein B and apolipoprotein A1: a narrative review. Nutrition Reviews. 2023; nuad102. doi:10.1093/nutrit/nuad102
18. Behre C, Bergström G, Schmidt C. Moderate physical activity is associated with lower ApoB/ApoA-I ratios independently of other risk factors in healthy, middle-aged men. Angiology. 2010;61: 775–779. doi:10.1177/0003319710373746
19. Ren H, Liu Z, Zhou X, Yuan G. Association of sleep duration with apolipoproteins and the apolipoprotein B/A1 ratio: the China health and nutrition survey. NutrMetab (Lond). 2018;15: 1. doi:10.1186/s12986-017-0237-8