Lp(a) and ApoB blood test: what they measure and what your result means

Medically reviewed by Dr Lebeth Jacob · 21 October 2026

Quick answer: Lp(a) (lipoprotein little a) and ApoB (apolipoprotein B) give a more detailed picture of heart and stroke risk than a standard cholesterol test. Lp(a) is a type of cholesterol particle whose level is mostly set by your genes, so many experts recommend testing it at least once in adult life. ApoB counts the harmful cholesterol-carrying particles in your blood.

What are Lp(a) and ApoB?

Cholesterol travels in the blood inside particles called lipoproteins. The harmful ones, such as LDL, each carry one ApoB protein. So measuring ApoB tells you how many harmful particles you have, which can matter more than how much cholesterol they hold.

Lp(a) is a particle similar to LDL with an extra protein attached. A high Lp(a) raises the risk of heart attack, stroke and narrowing of the aortic valve in the heart. Your level is mostly inherited and stays fairly steady through life. About 1 in 5 people have a raised Lp(a).

Why are they tested?

  • A parent, brother or sister had a heart attack or stroke at a young age
  • You've had a heart attack or stroke without the usual risk factors
  • Your LDL cholesterol is high, or you have familial hypercholesterolaemia
  • You have type 2 diabetes, high triglycerides or extra weight, when ApoB can show risk that LDL misses
  • You want a fuller picture of your heart risk than a standard cholesterol test gives

What does a high Lp(a) result mean?

A high Lp(a) means you have a higher lifelong risk of heart and circulation problems. It doesn't mean you will have them. Because diet and exercise barely change Lp(a), the focus is on lowering your other risks: LDL cholesterol, blood pressure, smoking, weight and blood sugar.

A high Lp(a) runs in families, so your close relatives may want to be tested too.

What does a high ApoB result mean?

A high ApoB means you have more harmful cholesterol-carrying particles, which raises heart and stroke risk. It can be high even when LDL looks normal, especially in people with diabetes, high triglycerides or extra weight. ApoB comes down with the same changes that lower LDL: a diet lower in saturated fat, being active, losing extra weight and, if needed, statins.

What can affect your result?

  • You don't need to fast for Lp(a) or ApoB
  • Lp(a) changes very little over time, so one accurate test is usually enough
  • ApoB changes with diet, weight and cholesterol medicines, so it can be rechecked to see the effect
  • A recent illness or pregnancy can change results for a few weeks

When to see a GP

Your results report shows the laboratory's range and flags any result outside it. Speak to your GP if:

  • Your Lp(a) or ApoB is flagged high
  • You also have a family history of early heart disease or stroke
  • You have other risk factors, such as high blood pressure, diabetes or smoking, that haven't been checked

Call 999 for chest pain, or for signs of a stroke: face drooping, arm weakness or slurred speech.

How we test Lp(a) and ApoB

Lp(a) and ApoB need a sample taken from a vein, so they're tested at one of our 250+ partner clinics rather than with a home kit. Samples are analysed by a UKAS-accredited laboratory. Results are usually ready in 3–5 working days, with a doctor's comments on every result.

Tests that include Lp(a) and ApoB

Prices for in-clinic tests include your appointment. Compare every test with Lp(a) and ApoB in the biomarker explorer

Frequently asked questions

What is lipoprotein(a)?

A type of cholesterol particle, similar to LDL, with an extra protein attached. A high level raises heart and stroke risk, and is mostly inherited.

Can I lower my Lp(a)?

Diet and exercise make little difference, and most standard cholesterol medicines don't lower it much. New treatments are being studied. For now, the best approach is to lower your other risks, such as LDL cholesterol and blood pressure.

How often should Lp(a) be tested?

Usually once in adult life is enough, because it stays fairly steady. Your doctor may repeat it in some situations.

What is ApoB?

A protein found on every harmful cholesterol-carrying particle. Measuring it counts those particles, which can give a clearer picture of risk than LDL alone.

Is ApoB better than LDL?

For many people they tell a similar story. ApoB can be more useful if you have diabetes, high triglycerides or extra weight, when LDL can underestimate risk. ## Pilot complete: all 20 pages All 20 pilot pages are drafted. Three are loaded on the work-on theme for preview; the other 17 load once Dr Jacob has signed them off. | # | Page | URL | Home kit | Status | | --- | --- | --- | --- | --- | | 1 | Ferritin | /pages/biomarker/ferritin | Yes | On preview | | 2 | HbA1c | /pages/biomarker/hba1c | Yes | On preview | | 3 | Cholesterol | /pages/biomarker/cholesterol | Yes | On preview | | 4 | PSA | /pages/biomarker/psa | Yes | Draft | | 5 | CRP | /pages/biomarker/crp | hs-CRP only | Draft | | 6 | eGFR and creatinine | /pages/biomarker/egfr-creatinine | Yes | Draft | | 7 | Bilirubin | /pages/biomarker/bilirubin | Yes | Draft | | 8 | ALP | /pages/biomarker/alp | Yes | Draft | | 9 | Uric acid | /pages/biomarker/uric-acid | Yes | Draft | | 10 | TSH | /pages/biomarker/tsh | Yes | Draft | | 11 | Vitamin D | /pages/biomarker/vitamin-d | Yes | Draft | | 12 | Vitamin B12 | /pages/biomarker/vitamin-b12 | Yes | Draft | | 13 | Folate | /pages/biomarker/folate | Yes | Draft | | 14 | ALT | /pages/biomarker/alt | Yes | Draft | | 15 | GGT | /pages/biomarker/ggt | Yes | Draft | | 16 | Full blood count | /pages/biomarker/full-blood-count | No | Draft | | 17 | Testosterone and SHBG | /pages/biomarker/testosterone | Yes | Draft | | 18 | FSH | /pages/biomarker/fsh | Yes | Draft | | 19 | Cortisol | /pages/biomarker/cortisol | Yes | Draft | | 20 | Lp(a) and ApoB | /pages/biomarker/lipoprotein-a-apob | No | Draft | One thing for George: the cortisol page says honestly that one blood test can't measure long-term stress, but the product is called "Cortisol (Stress) Blood Test". Worth checking the product page wording matches before the marker page goes live. After sign-off: 1. Dr Jacob ticks each checklist and adds any edits or comments here. 2. I build each page's content from this doc (including her edits), check every source link, add the review date, and load all 20 onto the work-on theme. 3. George checks them on preview, then pushes the template live. The pages go public at that point. 4. I link marker names on product pages and the biomarker explorer to these pages, add them to llms.txt, and prepare the old-site redirect CSV for the CTO. 5. Track monthly: Search Console clicks and impressions per page, AI citations in Ahrefs, and clicks through to product pages.