Neha Pathak, MD, FACP, DipABLM: Welcome to the WebMD Health Discovered Podcast. I'm Dr Neha Pathak, WebMD's Chief Physician Editor for Health and Lifestyle Medicine. Today, we're talking about cholesterol, a word we're all familiar with, but one that many people don't fully understand until the day our doctor hands us a lab test, and suddenly every question we never thought to ask comes rushing in at once. Heart disease remains the leading cause of death in the United States, and high cholesterol is one of the key drivers of that risk. What makes it challenging is that high cholesterol has no symptoms.

You can feel completely fine and still be at risk for heart attack or stroke because of your cholesterol levels. Many people also have questions about what actually matters when it comes to cholesterol. Is it just about food? When should you get tested? What are some of the new cholesterol tests that are being recommended, and how do lifestyle, genetics, and medication all fit together?

Today, we're joined by Dr Ann Marie Navar. Dr Navar is a preventive cardiologist and associate professor of cardiology at UT Southwestern Medical Center. She's also the Secretary of the American Society of Preventive Cardiology, a fellow of the American Heart Association, and was involved in shaping the latest cholesterol guidance.

She'll help us break down what people need to understand about their cholesterol levels, what's changed, and what steps you can take to better protect your heart. Dr Navar, welcome to the WebMD Health Discovered Podcast.

Ann Marie Navar, MD, PhD: Well, thank you so much for having me.

Pathak: Well, I am very thankful to have you because I think it's so critical for us to understand the best evidence to protect cardiovascular health — so the health of our blood vessels, our heart, our brain. And our conversation is especially timely because the American College of Cardiology and other medical associations, including the groups that you work with, released new guidelines to help patients and doctors understand what cholesterol levels to aim for and what medications might help get us to these goals. So I'd love to start by taking a step back, though, first and just asking you about your own health discovery. What drew you to this work?

Navar: Well, I love this question. I actually got into this work because when I started off in medicine, I was interested in vaccines, and I thought I was gonna be an infectious disease doctor working on vaccines. I fell in love with cardiology on the clinical side, though, and so I had to figure out how to pivot my research. And it turns out the closest you can get to a vaccine for heart disease is cholesterol lowering.

And so that's how I became a preventive cardiologist, because I think about cholesterol and risk factor control in the same way that I think about vaccinations to prevent infectious diseases.

Pathak: Oh, that's a really, really interesting analogy. So let's dig in then by really just kind of taking a step back and helping us define cholesterol. So what is it that we're vaccinating ourselves against when we're managing our cholesterol?

Navar: Well, it can be kind of confusing, and I like to sort of simplify it in ways that I understand when I talk to my patients about it. So we usually think about good cholesterol and bad cholesterol. And briefly, cholesterol is not dissolved in our blood like sugar in sweet tea. It's actually packaged up and floats around in little lipoproteins, sort of like little meatballs that have cholesterol and triglycerides and a protein attached.

Bad cholesterol is the cholesterol that is going out into our bloodstream and has the potential to get stuck in our artery walls. Good cholesterol is cholesterol actually coming back to our liver, where it's then broken down and excreted into our gut. So that's sort of the high-level way we think about cholesterol — the stuff that can stick in our arteries, and then the other stuff, which is on its way out.

Pathak: That's great. And then we're hearing more now about other cholesterol tests beyond the standard panel that we think about usually, which is the good, the bad, triglycerides — things like lipoprotein(a), ApoB. Can you help us understand what are those pieces of our panel, and how do they play a role?

Navar: Well, at the risk of torturing the analogy, I'll extend my conversation about meatballs. So I told you that bad cholesterol are particles that have cholesterol and triglycerides on the inside and a protein on the outside. Well, all of the cholesterol particles that have the potential to get stuck in our arteries have a single protein on them called ApoB.

Now, most of our bad cholesterol particles are what we call LDL particles, or low-density lipoproteins, but there are other types of bad cholesterol particles like VLDL particles. So if we measure the ApoB, what we're doing is basically counting the number of bad cholesterol particles that we have.

And when we look at this epidemiologically, most people, if they have a high LDL cholesterol — that's a measure of the weight of cholesterol in those particles — also have a high number of those particles. So the LDL-C, if it's high, means the ApoB is also high, but that's not always the case. And sometimes people can have particles that don't have a lot of cholesterol in them, so their LDL looks low, but their ApoB is high.

And when we study this epidemiologically, it seems like ApoB is actually the better predictor of lipid-related risk. So if we know the ApoB, it doesn't really matter as much what the LDL-C is. And so the new guidelines have recommended, in people who have been on cholesterol medication who get to LDL goals, to check the ApoB and make sure that we're not falsely reassured, and that we've also reduced the number of bad cholesterol particles.

So to simplify it all, ApoB is a count of the bad cholesterol particles, whereas the LDL and VLDL is the weight of cholesterol in those particles.

Now, you also asked about Lp(a), and this becomes a bit of a letter salad. Lp(a) stands for lipoprotein(a), and what an Lp(a) particle is, is simply an LDL particle, which has cholesterol, triglycerides, and an ApoB attached. And then there's one extra protein that's stuck onto that particle called Apo(a). And that protein essentially supercharges that particle and makes it an extra bad LDL particle. And that's called a lipoprotein(a) particle.

Now, Lp(a) particles we know increase the risk of cardiovascular disease, heart attacks, and stroke. They are also, unlike LDL cholesterol, almost entirely genetic. So if you have a high Lp(a), it's been high since you were 10 or 12 years old, and there's a 50/50 chance that all your first-degree relatives have a high Lp(a) as well. So it's a genetic cholesterol that we don't pick up with the regular lipid panel. We have to actually measure it directly.

Pathak: With the updated guidelines, can you help us understand when we should start testing and the intervals that we should continue to follow up?

Navar: The screening testing is fairly unchanged from before. We still recommend that all children have a lipid panel tested between the ages of 9 and 11. That's really to look for genetic causes of high cholesterol — extremely high cholesterol called familial hypercholesterolemia. And for people who have a family history of that, we actually recommend screening children around the age of 2.

In adults, starting at the age of 19, we recommend getting a lipid panel done at least every five years. But more frequent testing is recommended for people with additional risk factors like diabetes or changes in their weight or other early heart disease risk factors who may want to be tested more frequently.

Pathak: And then to clarify around the ApoB test, would you ask for that, or is that something that your doctor would recommend if you're already on treatment?

Navar: There's two groups where ApoB can be helpful. I talked about one, which is in people who are on treatment who get to their LDL goal — to measure the ApoB to make sure that not just the particle weight, but the particle concentration is also controlled.

The other group that we specifically recommend, albeit less strongly than the former group, is people who have risk factors for having that discordance between ApoB and LDL cholesterol. And that's things like obesity, diabetes, high triglycerides. There are individual groups that are more likely to be fooled by your LDL if you're deciding to initiate treatment.

Actually, the recommendation that we made was you can consider it to enhance risk assessment. So that could be for anybody. There are groups that we talk about that are more likely to have a high ApoB and a normal LDL cholesterol.

I see ApoB as sort of a bonus. It's the sprinkles on the icing on the cake. For most people, if we could just get everybody to get their lipids checked regularly, we would be making a huge impact on population health. But if you're wanting to really overachieve on knowing all your data, an ApoB is absolutely reasonable, easy to measure as part of routine blood work.

Pathak: I think it's so important, your point around everyone getting checked at a population level, because a lot of us individually feel completely fine regardless of what our cholesterol is. So why does high cholesterol usually have no symptoms? What's happening silently in the body that makes it so dangerous?

Navar: It's the frustrating thing about this as a risk factor. You don't feel high cholesterol. You have to have cholesterol levels many multiple times the upper limit of normal to start having physical manifestations of high cholesterol, where you can actually see it build up in the eyes or in the tendons.

For most people with high cholesterol, it doesn't show itself, but it's starting to get trapped in the artery walls and build up over time. And we know that the process of atherosclerosis, where cholesterol buildup happens, happens slowly. It happens over decades, and usually people don't know it's there until some of that cholesterol breaks off.

And if it happens in the heart, that causes a heart attack. If it happens in the head, it causes a stroke. And by the time somebody's had a cardiovascular event, they've had cholesterol accumulating in their artery walls probably for decades.

That's the reason why a big push of our guidelines was to think about identifying people at high long-term risk of heart disease earlier, treating sooner, and thinking about reducing the cumulative exposure to high cholesterol over a lifetime to try to prevent that atherosclerosis from starting in the first place.

Pathak: I think that's really helpful, and I've seen it when we talk with our patients about the similarity with smoking. You don't anticipate that smoking is gonna cause heart-related risks the first time you pick up a cigarette. It's those years of smoking and the damage it does to you over time that causes the cardiovascular risks that we're talking about.

Navar: Exactly. We talk about lipid years just like you can talk about pack years. The other part of prevention that's nice is you actually don't have to lower cholesterol as much if you're trying to prevent heart disease in somebody who's at lower risk than you do if somebody's already had a heart attack or stroke.

My analogy for this is it's harder to put the horse back in the barn than it is just to keep it there in the first place. So for primary prevention — people who have either a cholesterol level of 160 or above, or people with a high 30-year risk who are maybe young and don't have a high 10-year risk of heart disease — we recommend treating to an LDL cholesterol less than 100.

In contrast, in people who are very high risk for heart disease, who have either a lot of calcium buildup in their heart arteries or somebody who's had a prior heart attack with multiple risk factors, we're treating to an LDL cholesterol less than 55.

So, you know, a lot of patients that I see are like, “I really don't wanna be on medication.” And I think once you've had a heart attack, the number of medications you have to take is really high. Whereas for prevention of heart disease, it's often just a single medication. Generic statins are usually enough to get patients to that less-than-100 goal.

Pathak: So as we're sort of thinking about prevention, management, and this lifelong thinking about it as a lifelong process and a lifelong journey, let's dig in a little to the lifestyle and everyday habits because we know that's the cornerstone of prevention, but also the cornerstone, even if you are going to start on medication for management. Can you help us understand everyday habits that most meaningfully impact cholesterol from food, smoking, exercise, activity levels? What are some of the changes that have the biggest bang for our buck?

Navar: The question about what lifestyle changes affect cholesterol, it's actually different than the question of what lifestyle changes affect heart disease. So as a preventive cardiologist, I spend a lot of time talking to my patients about the importance of lifestyle in prevention of heart disease.

That means following a heart-healthy diet that usually is more of a Mediterranean pattern, high in fruits and vegetables, whole grains, low in saturated fats, added sugars. So foundational is a heart-healthy diet and regular exercise. The American Heart Association guidelines recommend a target of 150 minutes a week of moderate-intensity activity, 75 minutes a week if it's high intensity.

And then perhaps the biggest thing is don't smoke. Smoking is, you know, we think a lot about smoking in lung cancer, but it actually is a major cause of cardiovascular disease. Now, those things prevent heart disease not because they lower cholesterol, they prevent heart disease because they are protective for our arteries in general.

And so, for people who are working really hard on their lifestyle, they may make substantial changes and lower their risk of a heart attack or stroke and not see the cholesterol move that much. And that can be really frustrating for patients. So we have to make sure people understand that. Diet is only a very small contributor to our cholesterol levels, but it's a major contributor to our overall risk.

So we do recommend diet and exercise as first-line. But for many people, especially those whose cholesterol is more than about 10 points away from target, most people who are farther away from their goal are still gonna need medication. But you can't take medicine and get your cholesterol to goal and then not exercise and eat poorly.

Good medications, but they're not magic bullets and they don't offset the risks of an unhealthy lifestyle. I'll also put in a plug. I think we're gonna be having, hopefully soon, new guidelines from the American Heart Association and the American College of Cardiology around cardiovascular prevention, and these prevention guidelines are really comprehensive and talk about all of the risk factors for heart disease, whereas our recent guideline was really just focused on cholesterol.

Pathak: I do wanna talk a little bit about genetic factors and why shifting cholesterol can sometimes be very difficult. So can you talk a little bit about genetic factors and what we're learning about how they drive cholesterol risk?

Navar: There's several ways that genetics play into this topic. The first is there are specific genetic changes that cause really high cholesterol, and there's a set number of those that we know exist. They're genetic mutations in the machinery of our cholesterol regulation, and when we find those, we call it familial hypercholesterolemia because those can get passed down from generation to generation.

A lot of people, though, with very high cholesterol have, it's genetic, but it's not what we call monogenic, meaning there's actually a bunch of different genes that each contribute a little bit to high cholesterol. And this can be frustrating for patients because I think the message about lifestyle has been so well communicated about its importance that we've started to think that all of our cholesterol is determined by our lifestyle.

And the reality is that a lot of it is determined by our genes and, in women, also our hormonal status. And so even when we make really big lifestyle changes, it's hard to get your cholesterol levels down by significant amounts to actually get you below goal. We don't have a genetic test to prove that, but I think it's helpful for people to understand that it's not always your fault that your cholesterol's high.

And, you know, with rare exceptions, I have seen people go carnivorous and have their LDLs jump over 300. But in general, it's really hard to make huge swings in your cholesterol with diet alone.

So a lot of it is genetic. There's also genetic risk factors for cardiovascular disease that have nothing to do with cholesterol, but just increase your global risk of heart disease. And we haven't found a smoking gun like we have with cholesterol mutations, but we can think about this as a polygenic risk, and there are scoring systems called the polygenic risk score, where you can look at a whole bunch of genes that may increase your risk of heart disease.

That is still a subject of some research, and there's some variability between which result you get depending on which test you run. And so we don't have any formal recommendations that everybody should have this done, but we do provide guidance on how you could incorporate that into your other risk factors so that if you have a high genetic risk and you're on the fence about whether or not to treat somebody as a doctor, or as a patient on the fence about whether or not to start therapy, you probably should go ahead and start it.

And then the final genetic piece here is the lipoprotein(a), which we talked about, is purely genetic. If your lipoprotein(a) is high, there's a 50-50 chance that each of your kids or your first-degree relatives, your siblings or your parents, also have a high Lp(a). It has absolutely nothing to do with diet or exercise. There's really not anything that we can do about it right now. You can't go back and pick your parents.

But we are hopefully looking to see therapies come out that can be used to lower lipoprotein(a), and we wanna know who may be eligible for those therapies. But more importantly, because Lp(a) increases risk of heart disease, we recommend intensifying cholesterol lowering in general to try to offset that risk.

So if you know your Lp(a) is high, you need to be really on the ball with every other risk factor that you can control to try to manage your global risk of a heart attack or stroke.

Pathak: So that then kind of leads down towards medication. So let's move in that direction and help us understand how you think about risk stratification because that helps us really think about the goal that we're setting for the LDL cholesterol. So walk us through what you're thinking about when you're trying to risk stratify the patient in your office.

Navar: There are some groups of people that we don't need to guess their risk of heart disease. If you've had a prior heart attack or stroke, you're at high risk. If you've had a coronary calcium score that shows a bunch of buildup of cholesterol in your arteries, either a score of 100 or above or at the 75th percentile for your age and sex, then you need to be on therapy to lower that risk.

Type 2 diabetes, for example, is another one where it's pretty much automatic high risk. Now for everybody else, there are risk calculators, and we've moved to the more accurate PREVENT ASCVD risk equations, which identify somebody's 10-year risk of a heart attack or stroke.

Or if you're less than 60, we'll also tell you what your risk is over a 30-year horizon because, you know, I tell my 40-year-olds, I'm not trying to keep you well for 10 years. I'm trying to keep you well for 30 or more. So that helps us understand the risk of heart disease that we're trying to address.

And there are some risks of therapy. The most significant one, at least as we formulated these guidelines, was a small but not zero risk of new-onset diabetes. And so we picked our threshold to balance the risk of diabetes versus the risk of heart attack or stroke.

Now it's really up to the individual patient to decide what's right for them. I have many patients who are much more afraid of a stroke or a heart attack than they are about diabetes. And the reality is there's a lot we can do to prevent diabetes, like regular exercise and a healthy diet.

So many people at even lower risk may consider cholesterol lowering to try to prevent a heart attack or stroke over the long term. There are other people who, regardless of their risks, just don't wanna take medications. And so foundational to our guideline is the concept of shared decision-making.

These are not rules for doctors to have to follow. We are not saying that everybody in the United States who meets one of these criteria has to start taking a statin. What we're saying is these are the patients who we may recommend statin therapy, and then you need to talk to your doctor or your clinician about whether or not that's right for you and it fits in with your goals.

So I think it would be unrealistic to assume that just because we recommend therapy, everybody's gonna start it. But I think a recommendation should be: you need to have a conversation about why this may help you and then make a choice based on your personal values and priorities of whether or not you wanna initiate therapy.

Pathak: And I'd love your guidance on another question that I often get from patients is, okay, you know, maybe I'll start this medication, I'll get to goal, and is there any chance that I can then come off? If I really change my lifestyle and shift my dietary pattern, how do you counsel patients that are tending in this direction with you?

Navar: It is very personalized. I actually do think that in highly motivated patients, high cholesterol can be motivating to make the lifestyle changes that you need to. If somebody's low risk or sort of borderline risk and they say, let me try lifestyle first, I'll give it a go, and we come back, we have to make sure we bring somebody back, repeat their cholesterol sooner than a year, and see where it's going.

And then we can reassess. And I say, if you made all these changes and you're not at goal, then we need to add something. If somebody's at higher risk, I don't think it's wise to wait to get the cholesterol down.

And the way I counsel my patients is say, let's do both and let's get you to goal. And if we see you start to really overachieve with diet and exercise, and if you're one of the people, and I say on average diet and lifestyle don't move the needle a ton, but there are patients who can have really big changes in their LDL with diet and exercise, and that's great.

So if we get you to your goal of 70 and then you make diet and lifestyle changes and you really go past that, then we can start to talk about pulling off the medication or maybe turning the dose down. Same thing if somebody's perhaps losing a lot of weight or, you know, having other big changes, getting their diabetes under control.

This is a dynamic situation, but I think in patients who have high risk, we know that these therapies work better the longer that you're on them, and I don't recommend to my patients to delay initiating therapy if you're at high risk of heart disease. I think we do both at the same time and see where you land.

Pathak: So I'd like to use the last few moments that we have together to ask you: often, high cholesterol is one of the first diagnoses that someone might have if they've been relatively healthy their whole lives. And so it is a big mental hurdle to start taking a medicine for the first time.

And I love what you said earlier, and I say something very similar: I'm not just treating you today. I'm really thinking about you 20 years from now. So anything that we're doing, we want to make sure is going to be helpful to both of those patients. All of those people along the way are my patients. It's not just the you that's sitting here today.

So what are the first two to three things you'd like someone who's listening today to do? What actionable things can they do today to improve their cholesterol profile or to identify that this might be a problem for them?

Navar: It can be challenging to get patients into a mind shift of initiating cholesterol medication because they often see it as, “I have a disease that I'm trying to treat.” The way I often frame this, especially if I'm in the sort of prevention patient that you talked about — this is their first or only risk factor, who may be reluctant to start therapy — is I say, “If there was a vitamin that you could take that had the same number of side effects as a placebo, that would lower your risk of a heart attack or stroke by 25% to 50% over your lifetime, would you take it?”

They say, “Oh yeah, absolutely.” You know, over half of us adults take some sort of a vitamin, often because they're trying to have long-term heart health.

I say, “Well, you know, it turns out those vitamins are regulated and have as much data for heart disease prevention as the bag of salad in the produce aisle.” So vitamins don't prevent heart attacks or strokes, and we've shown that in many, many studies, but statins do, and they're very safe. We've studied them in hundreds of thousands of patients.

So I see this as: your cholesterol doesn't mean that you have a disease. What your cholesterol means is that we have an opportunity for a therapy to initiate — essentially a vitamin for heart attack or stroke prevention — that, if we start early, can help keep you off medications for the long run.

You know, starting cholesterol medication in your thirties or forties, in particular if cholesterol is your only risk factor, it's like buying Apple stock in the eighties. You just get compounded benefit over time. And I truly believe the biology suggests, and the epidemiology is consistent, that lowering cholesterol early in life prevents atherosclerosis and can prevent a majority of the leading cause of death in the United States, which is ischemic cardiovascular disease.

So, you know, we need to shift the mindset. Lots of U.S. adults are interested in prevention. We have to think about cholesterol lowering as a preventive therapy, like we do vitamins, healthy diet, and lifestyle. The first step: go get your cholesterol checked, get your Lp(a) tested, and talk to your primary care clinician about what the best options are for your long-term heart health.

Pathak: So well said and so comprehensive. I want to thank you so much for those action items, and you certainly impacted how I'm going to be talking to my patients as well. So thank you so much for your time today.

Navar: Well, thanks again for having me, and thanks to the audience for tuning in. I would encourage everybody to visit heart.org for more information about cholesterol, treatment, and heart health.

Pathak: Thank you so much. I'd like to share my three key takeaways from our discussion with Dr Navar.

First, high cholesterol has no symptoms, which is why getting your numbers checked is crucial. If you can't quite remember the last time you had your cholesterol levels checked, it's time to take action. And while you're at it, ask your doctor to test for lipoprotein(a), or Lp(a). That's a test you should get one time. It's tightly linked to genetics, and it won't show up on a standard panel.

Second, if your cholesterol is elevated, there are really important medications that you should be thinking about. Along with changing your diet, statins are not something to fear. They've been proven to significantly lower the risk of heart attack or stroke. The earlier you start managing elevated cholesterol, the greater the compounding benefit over time.

And if a statin doesn't work for you, there are many other options to talk to your doctor about. So don't give up on finding something that brings your cholesterol to a safer range.

Finally, lifestyle medicine and medication work together to protect your arteries in ways neither can fully do alone. It's important to work with your healthcare provider to develop a plan that will work for you today and for the next 20 to 30 years.

To find out more information about Dr Navar, her work, cholesterol, and heart health, make sure to check out our show notes. For more information on cholesterol and how to understand your numbers, visit heart.org/KnowYourCholesterol.

Thank you so much for listening. Please take a moment to follow, rate, and review this podcast on your favorite listening platform. If you'd like to send me an email about topics you are interested in or questions for future guests, please send me a note at [email protected].

This is Dr Neha Pathak for the WebMD Health Discovered Podcast.