A lipoprotein(a) test is recommended for everyone at least once, ideally by age 30, and measures Lp(a), a genetic marker for heart disease risk that diet and exercise can’t change. Unlike Lp(a), the related marker ApoB is modifiable through lifestyle and medication, so testing both together shows your baseline genetic risk and what you can actually do to lower it. A high-risk Lp(a) result is generally 50 mg/dL or 125 nmol/L or above. Combining these labs with imaging like a coronary calcium score helps determine whether lifestyle changes alone are enough or if medication is worth discussing.

Most of us trust a standard cholesterol panel to tell the whole story about our heart health. But it doesn’t.

The traditional, standard panel misses two crucial markers: lipoprotein(a), which we call Lp(a) for short, and apolipoprotein B, or ApoB.

A lipoprotein(a) test, which we’ll focus on in this post, reveals important information about your genetic risk for heart disease. It’s information you need to know in order to take appropriate, proactive measures to maintain your cardiovascular health for a long and fulfilling life.

Let me explain what these markers are, why they matter, and how I use them with my patients.

What Is a Lipoprotein(a) Test, and Why Does It Matter?

The purpose of testing markers like LDL, HDL, ApoB, and Lp(a) is simple. I want to know your risk of developing premature heart disease, meaning heart disease that shows up before advanced age with the ability to cause serious illness or even death.

Lp(a) is unlike almost every other marker I check. It’s genetic. Diet, exercise, and lifestyle changes don’t move this number up or down. But that doesn’t mean it’s unimportant.

In fact, everyone should get a lipoprotein(a) test at some point in their life, a sentiment which the American Heart Association and others recently updated their guidelines to support. The reason? This test tells you quite clearly whether you’re genetically predisposed to premature heart disease.

What Exactly Is Lp(a)?

Cholesterol and triglycerides are essential fats your body needs for energy, hormone production, digestion, and more. But they don’t move through your blood on their own.

That’s where lipoproteins come in. They act as transport vehicles, carrying these fats through your bloodstream. You’ve probably heard of a few: LDL, HDL, and perhaps VLDL.

Lp(a) is a lesser-known variant of LDL. When your doctor checks your LDL, some Lp(a) may get swept up in that number, but you need a separate test to know your true Lp(a) level.

Here’s why that separation matters. You could have a low LDL and still carry a high Lp(a), which puts you at greater risk than your LDL number alone would suggest.

Because Lp(a) is genetically fixed, you can’t change it with medication or lifestyle. But knowing your number tells you how likely it is that lifestyle factors could lead to cardiovascular disease. For instance, if you smoke, have diabetes, or have high blood pressure, an elevated Lp(a) compounds your risk considerably. But more on that later.

Roughly 10 to 20% of the population has an elevated Lp(a). If yours comes back extremely high, treatments like apheresis or PCSK9 inhibitors exist to try lowering it, though the evidence that these actually reduce heart disease risk (rather than just the number itself) is still limited.

ApoB: The Modifiable Half of the Equation

This is where ApoB comes in, and why I test for it alongside Lp(a).

Unlike Lp(a), ApoB responds to lifestyle. A better diet, regular exercise, and sometimes medication can lower it meaningfully.

So what is ApoB?

Every particle that carries LDL, VLDL, and other “bad” lipoproteins through your bloodstream contains exactly one ApoB molecule. So your ApoB level essentially counts how many of those particles are circulating in your body.

That might sound like the same thing as measuring how much cholesterol you have in your system, but it’s different in a meaningful way.

Your LDL cholesterol report tells you how much total LDL cholesterol you have in your system. ApoB tells you how many particles of cholesterol you have floating in your blood.

This is why you’ll sometimes hear ApoB referred to as “particle number.” A smaller number of large particles is far less dangerous to your arterial walls than a larger number of small ones, even if the total amount of cholesterol is the same on paper.

In general, the target ApoB value for average-risk individuals is under 90 mg/dL, though ideal ranges for those with higher risk are often even lower. The excellent news is that when you reduce your ApoB through changes in daily habits, your added cardiovascular risk from this lifestyle-driven particle traffic goes down, even though your Lp(a) number doesn’t budge.

In short, Lp(a) tells you your baseline genetic risk, and ApoB tells you what you can actually do about it.

Who Should Get a Lipoprotein(a) Test, and When

Everyone should have a lipoprotein(a) test done at least once in their life. The earlier, the better, since earlier gives you more time to implement lifestyle changes and prevent the accumulation of risk. Ideally, I’d suggest getting it done before age 30.

The test is a simple blood draw, typically costing between $20 and $100 out of pocket.

Even if you already know you have a family history of heart disease, this test can fill in a piece of the genetic puzzle and give you a solid starting point from which to make proactive, beneficial change.

Getting an Elevated Result Without Panicking

When someone learns their Lp(a) or ApoB tests came back elevated, two reactions aren’t uncommon. Some patients panic. Others assume there’s nothing to be done and give up entirely.

Neither reaction serves you well.

Heart disease develops slowly over years and decades, so there’s no need for immediate alarm. But the sooner you know your risk, the more time you have to act on it.

Lifestyle still comes first, no matter what your Lp(a) shows. That means attention to all the Four Pillars of Health: sleep, exercise, nutrition, and stress elimination.

If your Lp(a) happens to be low, that’s genuinely good news, but it doesn’t mean you can ignore those pillars. Your overall risk is simply lower to begin with.

For reference, a high-risk Lp(a) result is generally considered at least 50 mg/dL or 125 nmol/L, depending on which unit your lab uses.

For many patients, an elevated number ends up being motivating rather than frightening. Knowing your real risk can be exactly what pushes you to finally commit to those lifestyle changes you’ve been putting off.

From Numbers to Action: Combining Labs With Imaging

Lp(a) and ApoB both tell you about future risk. They don’t tell you what’s already happening in your arteries right now.

For that, I turn to imaging, specifically a coronary calcium score or a CT angiogram. These tests show whether plaque has already begun building up today.

If imaging shows existing plaque, aggressive lifestyle changes and possibly medication become the priority, with the goal of stopping further buildup and reversing what we can.

Age matters here, too. If you’re in your 50s, 60s, or 70s and your calcium score or CT angiogram comes back clean, that’s often reassuring regardless of what your lipid numbers show.

But if you’re younger and imaging already shows some buildup, that’s a signal worth taking seriously. It suggests more progression is likely down the road unless you make changes now, while you still have the most time to work with. Lifestyle remains important, but this is often the point where we also discuss whether statin medication makes sense for your specific situation.

Lipoprotein(a) Testing: The Bottom Line

While a standard cholesterol panel is a useful starting point, it falls short of the full picture of your heart disease risk.

A lipoprotein(a) test, paired with ApoB, fills in the detail that LDL and HDL numbers simply can’t capture on their own.

I recommend everyone get this testing done at least once, and the major guideline-setting organizations now agree. Knowing your numbers early gives you the most time to act on them, whether that means doubling down on the Four Pillars of Health or having an informed conversation with your physician about medication.