Nicolette: 0:01

Welcome to the Health Pulse, your go-to source for quick, actionable insights on health, wellness and diagnostics. Whether you're looking to optimize your well-being or stay informed about the latest in medical testing, we've got you covered. Join us as we break down key health topics in just minutes. Let's dive in.

Mark: 0:24

Welcome to the Deep Dive. Today we're getting into something really vital for your long-term health. It's all about understanding your cholesterol panel.

Rachel: 0:34

And not just the numbers but the bigger picture, right your metabolic well-being.

Mark: 0:37

Exactly. We're using insights from Dr Robert Lustig, specifically from a YouTube video he did. You might have seen it it's on the Levels channel.

Rachel: 0:46

Yeah, the one called Understand your Cholesterol Panel and Metabolic Health Tests, the Ultimate Guide. We're working off the transcript from that.

Mark: 0:53

Right, and our mission today is pretty straightforward Cut through all the you know the confusion around these lab results.

Rachel: 0:59

So you can actually get some actionable knowledge, understand what's really happening inside your body.

Mark: 1:04

It's fascinating, isn't it, how these tests. They seem routine, but they're all connected.

Rachel: 1:09

Totally. We just see this list, maybe some red flags, green check marks. But Dr Lustig really shows how it's like a dynamic story, your metabolic story.

Mark: 1:19

Okay, let's jump right in Total cholesterol. Dr Lustig basically says throw it out, ignore it. Why so strong?

Rachel: 1:26

Well, the thing is total cholesterol. By itself it doesn't tell you much about your actual heart disease risk. It's kind of like knowing the total cars on a highway.

Nicolette: 1:36

OK.

Rachel: 1:37

But you don't know if they're like safe minivans or you know a bunch of Ferrari speeding.

Mark: 1:42

Right, so the total number could be high because of the good stuff, exactly.

Rachel: 1:46

It can be misleading. So the main point is don't obsess over total cholesterol. It's the types of cholesterol that really count for understanding your risk.

Mark: 1:55

That makes perfect sense. Okay, so let's zoom in LDL cholesterol. This is the one everyone calls the bad cholesterol, the one people worry about.

Rachel: 2:02

Yeah, and look, there's a reason. Big population studies do show a link, right, higher LDL, more heart disease risk. But the, let's say, intense focus on LDL in medicine. It's been heavily influenced by the history of statins, ah, the drugs that lower it very effectively, right. And Dr Lustig points out, the actual hazard risk ratio for high LDL is about 1.3. So there's an association, sure, but maybe it's not the whole story people think it is.

Mark: 2:30

OK, and this is where it gets. I think really, really interesting. Dr Lustig says there isn't just one type of LDL.

Rachel: 2:38

Exactly that's crucial. You basically got two main kinds large buoyant LDL particles and small dense LDL particles.

Mark: 2:48

Small and dense versus large and buoyant. What's the difference?

Rachel: 2:51

Well, the standard LDL test. It just measures the total amount. It lumps them both together, but the evidence strongly suggests it's mainly the small, dense LDL that's linked to heart disease developing. The large buoy type seems much less concerning, maybe even neutral.

Mark: 3:07

Wow, okay, so you could have a high LDL number on your report, but maybe, just maybe, it's mostly the less harmful large kind.

Rachel: 3:17

That's the possibility.

Mark: 3:18

Yes, a key distinction. But then the million-dollar question is how do you know which type is dominating your results if the standard test doesn't tell you?

Rachel: 3:26

And that question leads us straight to another number on that panel triglycerides. Now, these have had a bit of a checkered history.

Mark: 3:32

Why is that?

Rachel: 3:32

Because non-fasting samples can really mess up the results.

Mark: 3:35

Right, like if you just had I don't know a big glass of orange juice or something sugary before the test.

Rachel: 3:39

Precisely. It skews things badly. But and this is key when you measure triglycerides after a proper fast, they actually become a more significant predictor of heart attack risk than LDL is.

Mark: 3:51

Really More significant.

Rachel: 3:52

Yeah, the hazard risk ratio is around 1.8 for triglycerides, compared to that 1.3 for LDL we mentioned.

Mark: 3:58

Huh, so why haven't we heard as much focus on triglycerides then?

Rachel: 4:02

Well, dr Lustig suggests one possible reason is historically there just haven't been as many blockbuster widely used drugs specifically targeting high triglycerides compared to statins for LDL.

Mark: 4:14

Interesting point. Okay, so fasting triglycerides very important. How do they connect back to those different LDL types, the small, dense versus large, buoyant?

Rachel: 4:24

This is the critical link. High fasting triglycerides often mean you have a higher proportion of those harmful small dense LDL particles.

Mark: 4:33

Okay, how does that work?

Rachel: 4:34

Think of it like this when you eat excess sugar or carbs that break down quickly into sugar, your liver takes that sugar and converts it into something called VLDL, very low density lipoprotein.

Mark: 4:46

VLDL Got it.

Rachel: 4:47

And in a fasting state, your triglyceride level basically is your VLDL level. They're measuring the same thing essentially. Then these VLDL particles go out into your bloodstream, they get processed, lipids get dropped off and what's left eventually becomes that small dense LDL.

Mark: 5:05

Ah, so high triglycerides are like an upstream indicator for more small dense LDL downstream.

Rachel: 5:11

Exactly. It's a very strong clue that more of your LDL is likely the problematic type.

Mark: 5:16

Got it so. Too much sugar drives up triglycerides. High triglycerides suggest more of the bad LDL. What about HDL, the good cholesterol?

Rachel: 5:24

Right HDL High-density lipoprotein. Its main job is really important. It acts like a scavenger.

Mark: 5:29

How so.

Rachel: 5:29

It helps transport fats, lipids, away from your tissues like fat cells and back towards the liver for processing, maybe removal.

Mark: 5:36

And it's high-density.

Rachel: 5:37

It's packed with protein relative to the fat it carries, makes it denser. Okay, and general, higher HDL is good. Generally, yes, higher HDL levels are linked with a protective effect against heart disease because of that reverse transport rule. There are some rare exceptions, like HDL Milano, but for most people, yeah, you want healthy, robust HDL levels.

Mark: 5:56

Now Dr Lustig puts a lot of emphasis on a specific calculation the triglyceride to HDL ratio. Why look at that ratio specifically?

Rachel: 6:05

This ratio. It really gained traction thanks to Dr Jerry Riven's work on metabolic syndrome. It's just a really powerful snapshot of your heart disease risk.

Mark: 6:14

Why does it do that?

Rachel: 6:15

Well, think about it. It directly compares the bad guy, triglycerides, which we now know are a proxy for small dense LDL, with the good guy, hdl, the protective cholesterol.

Mark: 6:25

So it's like a balance scale for those key lipid players.

Rachel: 6:28

Exactly, and interestingly this ratio can also serve as a sort of poor man's marker for insulin resistance. We'll definitely circle back to that.

Mark: 6:36

Okay, good. So this ratio gives a sense of balance. What numbers should people be looking for? What's a good target?

Rachel: 6:42

Generally speaking, you want that ratio to be 1.5 or less. That's considered pretty favorable.

Mark: 6:47

Okay, 1.5 or less.

Rachel: 6:48

If it starts creeping up. A ratio of 2.5 or greater suggests there might be a problem. Higher risk.

Mark: 6:55

And you mentioned race differences.

Rachel: 6:57

Yeah, there's some data suggesting that for African-Americans the ideal target might be a bit lower, closer to 1.5 or even below that, but the general principle holds lower is better. It's a snapshot of your lipid dynamics, right then?

Mark: 7:11

It really sounds like this ratio tells a much richer story than just you know, looking at the LDL number and see if it's got a green check or a red flag next to it.

Rachel: 7:19

Absolutely. It's a shame really, the common practice of just glancing at individual numbers within the normal range. It often misses these crucial relationships, these patterns.

Mark: 7:29

You miss the interaction between them.

Rachel: 7:30

Precisely.

Mark: 7:31

Okay, let's dig back into that small dense LDL. We know it's the one we're more worried about, the one linked to plaque. What else is important here?

Rachel: 7:39

Well, first, a practical point Dr Lustig makes To interpret your lipid profile accurately, you need to be, you know, generally healthy at the time of the test, meaning no acute illness like a bad cold or infection which would show up in your white blood cell count that can affect lipids Okay. And also your thyroid function needs to be stable, specifically your free T4 level.

Mark: 8:02

Why thyroid?

Rachel: 8:03

Because hypothyroidism an underactive thyroid can actually falsely increase your triglyceride levels. Ah, good to know. He even gives a quick mention to Hashimoto's thyroiditis as a common cause and notes you can sometimes use, you know, holistic or complementary approaches alongside medication.

Mark: 8:20

Right. Important context these numbers don't exist in a vacuum. Ok, back to the LDL particles themselves Large versus small.

Rachel: 8:27

So, as we said, the large boyan LDL that's most of it, maybe 80 percent Seems pretty neutral cardiovascularly, Like bigger, fluffier beach balls maybe.

Mark: 8:37

OK.

Rachel: 8:37

The small, dense LDL. That's a smaller fraction, maybe 20 percent, but that's the type that can wiggle its way under the lining of your arteries, the endothelium.

Mark: 8:45

And start causing trouble.

Rachel: 8:47

Yeah, that's how plaque formation begins. They're smaller, denser, they sink in lab tests and they tend to be more inflammatory. And again, your standard LDL test doesn't separate these two.

Mark: 8:58

So how do we get a clue about whether we have more of this problematic small dense LDL? We're back to triglycerides again.

Rachel: 9:06

We are indeed High. Triglycerides are your strongest indirect indicator that you likely have more small dense LDL floating around.

Mark: 9:14

Because remind us of that link again.

Rachel: 9:15

Because VLDL, which is what your fasting triglyceride level is, is the precursor particle. It gets processed by the liver and fat cells, lipids are removed and what's left over eventually becomes that small dense LDL.

Mark: 9:27

Okay, let's really hammer home this VLDL and sugar connection. It seems so central.

Rachel: 9:31

It is absolutely central In that fasting state. Remember, triglyceride level equals VLDL level.

Mark: 9:36

Got it.

Rachel: 9:36

And here's the kicker your liver makes VLDL primarily in response to sugar.

Mark: 9:43

Not fat. I thought cholesterol came from fat.

Rachel: 9:45

Well, dietary fat leads to different particles called chylomicrons, which clear pretty quickly after a meal and don't really affect your fasting triglyceride number, unless you have a very rare genetic issue like type 5 hyperlipoproteinemia.

Mark: 9:58

Okay, so chylomicrons are from dietary fat, short term VLDL is from VLDL reflected in your fasting.

Rachel: 10:06

Triglyceridesides is the liver's response to excess carbohydrates, especially refined sugars and things that digest quickly into sugar.

Mark: 10:13

So the sugar you eat gets turned into fat triglycerides, VLDL, by your liver.

Rachel: 10:19

That's the key takeaway.

Mark: 10:24

Fasting triglyceride. Vldl equals liver processing sugar. This explains so much like why Dr Lustig sees triglycerides drop dramatically when people cut back on sugar.

Rachel: 10:31

Exactly, it happens quite quickly sometimes.

Mark: 10:33

And it also highlights, like you said, the missed opportunities in standard interpretation.

Rachel: 10:37

Totally. Someone might have LDL. That's just a bit high. Maybe HDL is a bit low. Triglycerides are borderline.

Mark: 10:42

And individually. The doctor says you're fine.

Rachel: 10:45

Right. But when you look at those numbers together, especially with that triglyceride HDL ratio, it can scream metabolic issues brewing, even if nothing is technically in the red zone.

Mark: 10:55

It's about the pattern, not just the isolated dots.

Rachel: 10:57

Precisely, and these numbers aren't set in stone, they're dynamic, you can change them with lifestyle. Reducing sugar is a huge lever there.

Mark: 11:05

Which brings up a bigger point Dr Lustig touches on. Maybe the training doctors get needs adjusting.

Rachel: 11:12

Well, he notes that primary care physicians often don't get super deep training in lipidology, the specifics of lipid metabolism.

Mark: 11:19

So the approach becomes a bit simplistic.

Rachel: 11:23

It can be. Sometimes it's just LEL, high statin, triglycerides, high maybe a fibrate, without always digging into the why, the underlying metabolic engine driving those numbers.

Mark: 11:33

And he also pushes back against the idea that metabolic health is just about weight right.

Rachel: 11:38

Absolutely. He debunks that myth pretty firmly. You can be thin but metabolically unhealthy to a five. Thin on the outside, fat on the inside.

Mark: 11:45

With a terrible lipid profile.

Rachel: 11:47

Exactly, and, conversely, someone who carries more weight might actually be metabolically quite healthy. It's not about the subcutaneous fat, the fat under your skin.

Mark: 11:56

It's the visceral fat.

Rachel: 11:57

Yes, especially fat in the liver. That's the real metabolic troublemaker and it's largely driven by excess sugar, not just overall calories or visible body fat.

Mark: 12:06

Okay, this is all incredibly insightful.

Rachel: 12:08

Yeah.

Mark: 12:09

So for people listening wanting to understand their own results, what's the practical game plan?

Rachel: 12:14

Okay, first step, you get your results. If your LDL is a little high, don't freak out immediately. Okay, breathe. Look straight at your triglyceride number and your HDL number. Calculate that triglyceride to HDL ratio.

Mark: 12:30

What's a good triglyceride?

Rachel: 12:30

number on its own. Generally, if your triglycerides are under 100 milligdl, that's usually a good sign. It suggests you probably don't have a ton of that small dense LDL.

Mark: 12:38

Below 100 is good. What if it's higher?

Rachel: 12:40

If it's higher, then you really need to look at it in relation to your HDL. Using that ratio, Remember the connection Triglycerides become small dense LDL.

Mark: 12:48

While HDL is trying to clean things up.

Rachel: 12:52

Right, and that ratio, the triglyceride HDL, as we mentioned, is also a decent proxy for insulin resistance.

Mark: 12:58

OK, insulin resistance we hear that term constantly. Now let's unpack its role here.

Rachel: 13:02

It's absolutely central to this whole metabolic picture. People think of insulin as just the diabetes hormone regulating blood sugar.

Mark: 13:10

But it's more than that.

Rachel: 13:11

Oh yeah, its primary job is actually being the energy storage hormone. It tells your body what to do with the energy you consume, store it. Primarily store it. Yes, Especially excess energy. It pushes it into fat cells under the skin, around organs and, crucially, into the liver.

Mark: 13:29

And insulin resistance is when.

Rachel: 13:31

It's when your cells, particularly your liver cells, become kind of numb to insulin signal, often because they're already stuffed with fat.

Mark: 13:38

So they don't respond properly.

Rachel: 13:40

Right, and because the signal isn't getting through effectively, your pancreas thinks, uh-oh, need to shout louder, and it pumps out more insulin to try and force the message through.

Mark: 13:49

And the liver is ground zero for this. You mentioned the portal vein.

Rachel: 13:52

Exactly right. The blood leaving your pancreas loaded with freshly made insulin goes straight into the portal vein which leads directly to the liver, gets the highest concentration.

Mark: 14:02

So the liver's health is paramount for insulin signaling.

Rachel: 14:06

Absolutely. And when the liver gets fatty, which is incredibly common now, maybe affecting 45% of US adults. Some estimates say Wow 45%. Yeah, it's epidemic. When the liver's fatty, it resists insulin, making the pancreas work overtime, leading to chronically high insulin levels.

Mark: 14:23

And high insulin isn't just about blood sugar.

Rachel: 14:25

No High insulin itself that hyperinsulinemia is linked to a whole host of chronic diseases Heart disease, yes, but also certain cancers, dementia, pcos, the list goes on. Insulin is essential, but too much for too long due to resistance is bad news.

Mark: 14:41

Okay, so clearly understanding our insulin sensitivity is key. How can we measure that, besides just looking at blood sugar?

Rachel: 14:47

Well, in research they use a calculation called OCHIONEIR sure homeostatic model assessment for insulin resistance.

Mark: 14:53

Sounds complicated.

Rachel: 14:54

It uses your fasting insulin level and your fasting glucose level. You can actually find calculators online for it, like on MDCalc, if you have those two numbers. Okay, h-o-a-i-r, but you also said I also said that triglyceride to HDL ratio we keep talking about is a surprisingly good, readily available proxy for insulin sensitivity Much easier to get.

Mark: 15:13

And what about directly measuring the small dense LDL?

Rachel: 15:17

You can get tests for LDL, particle size or number, but they're often not standard, might not be covered by insurance, cost more, so they aren't routine for most people yet.

Mark: 15:26

Right, which brings us back to insulin. Could you just ask for a fasting insulin test?

Rachel: 15:31

You can, and it's a really valuable test for metabolic health. It's a separate blood draw, usually not part of the standard chemistry panel.

Mark: 15:37

But there's some controversy, isn't there? The American Diabetes Association advises against it.

Rachel: 15:42

Yes, they do, somewhat controversially, dr Lustig discusses their reasons and pushes back.

Mark: 15:47

What are their reasons?

Rachel: 15:48

Okay. Reason one lack of standardization, meaning the lab methods, the assays for measuring insulin can vary a bit, lab to lab giving slightly different numbers.

Mark: 15:59

OK, that sounds like a potential issue.

Rachel: 16:00

It is to a degree. But Dr Lustig's point is, even with that variability, if your level is consistently high, it still means something is wrong. It indicates your pancreas is under stress.

Mark: 16:12

Even if the exact number is slightly fuzzy.

Rachel: 16:14

Right, and some assays might also pick up pro-insulin, which is like a precursor to active insulin. But again, high levels of that also indicate the pancreas is working too hard. So it doesn't invalidate the test's usefulness in signaling a problem.

Mark: 16:29

Okay, what's the ADA's second argument against routine testing?

Rachel: 16:33

They say insulin levels don't correlate perfectly with obesity.

Mark: 16:37

And Dr Lusdy's response.

Rachel: 16:38

He agrees, but he says that's precisely why you should measure it. It tells you about metabolic health independent of weight.

Mark: 16:44

Ah, like the TOFI, concept again.

Rachel: 16:46

Exactly, you can be lean with high insulin, metabolically unhealthy or obese. With normal insulin, metabolically healthier.

Mark: 16:57

The insulin level reflects the underlying metabolic function, not just the number on the scale, so it seems like a really useful test that's maybe underutilized. If someone does get a fasting insulin test, what are they hoping to see? What are good levels?

Rachel: 17:06

Well, generally, the lower the better. Truly Elite marathon runners might be down around two micro IU per ml.

Mark: 17:13

Wow, okay, for the rest of us.

Rachel: 17:15

Generally under 6 or 7 is considered quite good. Under 10 is probably still okay.

Mark: 17:20

And when do you start getting concerned?

Rachel: 17:22

When levels are consistently creeping above 10, that raises a flag for insulin resistance and if you're seeing levels of 15 or higher, that strongly suggests significant insulin resistance is present.

Mark: 17:33

And that high level points towards.

Rachel: 17:35

It points towards litter dysfunction, liver fat usually, and a pancreas that's really straining to keep up.

Mark: 17:41

This keeps coming back to liver, doesn't it? Its health seems critical.

Rachel: 17:45

Absolutely critical, and liver function tests, or LFTs, are often glanced over unless something is wildly abnormal like high bilirubin causing jaundice.

Mark: 17:53

But there's more subtle information there.

Rachel: 17:55

Definitely Specifically look at the ALT level alanine aminotransferase it used to be called SGPT.

Mark: 18:02

ALT. What does that tell us?

Rachel: 18:04

ALT is a really good indicator of liver fat. When liver cells are damaged or stressed, often by excess fat, they leak ALT into the bloodstream.

Mark: 18:12

And what's considered a normal ALT level, because those ranges on lab reports can be wide.

Rachel: 18:17

They can. And Dr Lustig points out something crucial the upper limit of normal for ALT has actually crept up over the years. It used to be maybe 25. Now it's often 40 or even higher on lab reports.

Mark: 18:29

Why'd it go up?

Rachel: 18:30

Because the average population has gotten unhealthier, specifically with more fatty liver disease, the normal range shifted to reflect the less healthy average not necessarily what's optimal, so using that higher range might mask problems. What ALT levels should make us pay attention? Dr Lessig argues pretty strongly that an ALT level consistently above 25, maybe even above 20 for African-Americans should be considered suspicious for liver fat until proven otherwise.

Mark: 18:56

Above 25, that's much lower than the usual cutoff.

Rachel: 18:59

It is. His point is don't wait for it to hit 40 or 50. An ALT creeping above 25 suggests something's going on in the liver that needs addressing. The goal is to get the fat out of the liver.

Mark: 19:10

Because clearing liver fat improves liver function.

Rachel: 19:12

Improves liver function, which helps lower insulin levels, which helps prevent all those downstream metabolic diseases we talked about. It's all connected.

Mark: 19:20

Okay, wow, we've covered a lot of ground. Let's try and quickly recap the main takeaways for everyone listening.

Rachel: 19:25

Sounds good. Okay, number one total cholesterol. Not that useful on its own, don't fixate on it.

Mark: 19:31

Right Number two LDL alone isn't enough either. You have to look at triglycerides and HDL too.

Rachel: 19:37

Absolutely Number three. That triglyceride to HDL ratio is key. Aim for under 2.5, ideally under 1.5, especially for African-Americans. Lower is better.

Mark: 19:48

Okay, four triglycerides themselves under 100 is generally a good sign. Suggests less of the harmful small dense LDL.

Rachel: 19:56

Yep Five aim for higher HDL, well above those minimums on the lab report. Genetics plays a role, but lifestyle helps.

Mark: 20:02

Six remember the sugar connection. Excess sugar dries liver fat.

Rachel: 20:06

Which leads to insulin resistance and the production of that bad small dense LDL. It's a chain reaction.

Mark: 20:14

Seven pay attention to your ALT liver enzyme. If it's consistently over 25, investigate for liver fat.

Rachel: 20:20

Don't wait for to be sky-high right and finally eight, consider asking your doctor about a fasting insulin test.

Mark: 20:26

Aim for under six or seven, ideally and if you can't get the insulin test, really focus on that triglyceride to HDL ratio as your next best indicator.

Rachel: 20:36

Exactly that ratio gives you a lot of insight.

Mark: 20:39

This deep dive. Hopefully it's giving you, the listener, a much clearer, more nuanced way to look at your cholesterol panel. It's not just numbers.

Rachel: 20:47

Not at all. They really do tell a story, don't they? A story about how your body is handling energy, day in and day out.

Mark: 20:53

So here's maybe a final thought to leave you with. We've seen how powerfully sugar impacts. These numbers impacts your metabolic health.

Rachel: 20:59

Yeah, it's profound when you connect the dots from the diet to the liver, to the lipids, to insulin.

Mark: 21:03

So the question for you is knowing this, what small, maybe seemingly insignificant, change could you make, starting today, to begin shifting these markers to protect your health long-term?

Rachel: 21:14

The answers might actually be simpler than you think, and just understanding these connections we've talked about that's a huge, powerful first step.

Nicolette: 21:29

Thanks for tuning into the Health Pulse. If you found this episode helpful, don't forget to subscribe and share it with someone who might benefit. For more health insights and diagnostics, visit us online at wwwquicklabmobilecom. Stay informed, stay healthy and we'll catch you in the next episode.