The myth of mild coronary disease

I hear this comment from patients all the time:

"They told me that I had only mild blockages and so I had nothing to worry about."

That's one big lie.

I guess I shouldn't call it a lie. Is it a lie when it comes from ignorance, arrogance, laziness, or greed?

"Mild coronary disease" is usually a label applied to coronary atherosclerotic plaque that is insufficient to block flow. Thus, having a few 20%, 30%, or 40% blockages would be labeled "mild." No stents are (usually) implanted, no bypass surgery performed, and symptoms should not be attributable to the blockages. Thus, "mild."

The problem is that "mild" blockages are no less likely to rupture, the eruptive process that resembles a little volcano spewing lava. Except it's not lava, but the internal contents of atherosclerotic plaque. When these internal contents of plaque gain contact with blood, the coagulation process is set in motion and the artery both clots and constricts. Chest pains and heart attack result.

So, the essential point is not necessarily the amount of blood flow through the artery, but the presence of coronary atherosclerotic plaque. Just having plaque--any amount of plaque--sets the stage to permit plaque rupture.

One thing is clear: The more plaque you have, the greater the risk for rupture. But the quantity of plaque cannot be measured by the "percent blockage." It is measured by the lengthwise extent of plaque, as well as the depth of plaque within the wall. Neither of these risk features for plaque rupture can be gauged by percent blockage.


Coronary atherosclerosis is a diffuse process that involves much of the length of the artery. It is therefore folly to believe that a 15 mm long stent has addressed the disease. This is no more a solution than to replace the faucet in your kitchen in a house with rotting pipes from the basement up.

The message: ANY amount of coronary plaque is reason to engage in a program of prevention--prevention of plaque rupture, prevention of further plaque growth, perhaps even regression (reversal). It is NOT a reason to be complacent and buy into the myth of "mild" coronary disease, the misguided notion that arises from ill-conceived procedural heart disease solutions.


Image courtesy Wikipedia.

Copyright 2008 William Davis, MD

Red flags for lipoprotein(a)



Lipoprotein(a), Lp(a), is an important cause for heart disease, heart attack, and coronary atherosclerotic plaque.

How do you know you have it?

Of course, it could be as simple as checking a blood level. But there are also a number of red flags for the presence of Lp(a), tell-tale signs that suggest it is present and contributing to the growth of coronary plaque.

I've seen so much of this pattern over the years that it's gotten so that I can pretty much pick out most of the people with Lp(a) just by either looking at them or by hearing their story. I do this simply by knowing what hints to look for.

Some of the red flags for Lp(a) include:

--High blood pressure in a slender person. Overweight is the overwhelmingly common reason for high blood pressure. However, inappropriate high blood pressure in a slender person can serve to tip you off that Lp(a) is present.

--HIgh LDL cholesterol poorly responsive to statin drugs. For instance, someone's LDL cholesterol of 190 mg/dl will be treated with Lipitor 40 mg, but drops to only 165 mg/dl, a very poor response. This can sometimes point towards Lp(a).

--Family clustering of heart disease in people before age 60. For instance, father with heart attack age 53, uncle with heart attack at age 55, aunt with heart attack age 59, etc. This clustering of risk, more often than not, signals Lp(a).

--Coronary disease or high heart scan score in the presence of relatively bland appearing lipids. For instance, LDL cholesterol 130 mg/dl, HDL 55 mg/dl, triglycerides 70 mg/dl on no medications or other efforts--figures ordinarily not associated with high likelihood of heart disease--yet heart disease is indeed present. This can mean that Lp(a) is the concealed culprit behind coronary atherosclerosis.

These red flags are not perfect. If you lack any of them, it doesn't necessarily rule out the possbility of having Lp(a). They simply serve as signs to suggest that Lp(a) may be lurking.

Once Lp(a) is identified, then the battle begins to gain control over this somewhat troublesome genetic pattern. Resourcesfulness and some ingenuity may be required. However, knowing that you have it shows you where to concentrate your efforts.

Vytorin study explodes--But what's the real story?

The makers of Vytorin, Merck/Schering-Plough Pharmaceuticals, issued a press release about the the Enhance Study yesterday. The news has triggered a media frenzy.

The NY Times reporting of the story:

Drug Has No Benefit in Trial, Makers Say

The 700 participants in the trial all had a condition called "heterozygous hypercholesterolemia," a genetic disorder that permits very high LDL cholesterols. The average LDL at the start was 318 mg/dl.

The Times reported that, while Vytorin cut "LDL levels by 58 percent, compared to a 41 percent reduction with simvastatin alone," but "the average thickness of the carotid artery plaque increased by 0.0111 of a millimeter in patients taking Vytorin, compared to an increase of 0.0058 of a millimeter in those taking only simvastatin." There was no difference in heart attacks or other "events" between the two groups.

(Vytorin is the combination of simvastatin and Zetia.)

In other words, the participants taking Vytorin had 53 ten-thousands of a millimeter more plaque growth than the group taking just simvastatin.

I am always uncomfortable when put in the position of defending a drug or drug company. However, it is patently absurd that this study has generated such attention. I suspect the public and media are waiting for another Vioxx-like debacle, with memories of concealed or suppressed data that suggested heightened heart attack risk that was dismisssed by the drug manufacturer. (That's not to say that the company hasn't been trying to delay or modify the outcome of the study, which they apparently have, much to the objections of the FDA.)

However, at this point, there is no reason to believe that this question possesses any parallels to the Vioxx fiasco.

If we accept the data as reported, however, we might say it calls the entire "Lipid Hypothesis" into question: If LDL cholesterol is significantly reduced but is not correlated with reduction in plaque, is LDL the means by which atherosclerotic plaque progresses? This trial does not answer that question, but does serve to raise some doubt.

Another issue: Heterozygous hypercholesterolemia, and thereby LDL cholesterol, may not be the overwhelming driver of plaque growth in this population. It is probably the number of small LDL particles, a factor which is not revealed by LDL cholesterol. For this reason, heterozygous hypercholesterolemia by itself is insufficient to cause heart disease. Some other factor(s) needs to be present. I would propose that it is the size of the LDL particle: When small, heart disease develops; when large, heart disease is less likely to develop. This issue was not addressed by this study. Readers of The Heart Scan Blog know that conventional LDL cholesterol, the number used in this study, is a virtually worthless number for truly gauging plaque behavior because of its flagrant inaccuracy.

So, there are substantial uncertainties, contrary to the absolute certainty expressed by people like Dr. Steve Nissen (who, by the way, has no expertise in lipoprotein disorders). It is premature to reach any firm conclusions from this study. The only conclusions that I personally come to are 1) Is this yet another reason to question the entire Lipid Hypothesis as it stands? and 2) What would the results have been had LDL particle number and LDL particle size been examined, not just LDL?

I would not automatically conclude that Zetia causes carotid plaque. This is absurd. And I am definitely not one to come to the rescue of a drug or drug manufacturer. I am simply after understanding and truth.

As an interesting aside, Dr. Howard Hodis of the University of Southern California and an expert in carotid scanning for heart disease prevention research, made a comment relevant to us in the Track Your Plaque program:

"Clearly, progression of atherosclerosis is the only way you get events,” Dr. Hodis said. “If you don’t treat progression, then you get events."

Dr. Arthur Agatston in the news



The Miami Herald has a new report on Dr. Arthur Agagtston (of South Beach Diet fame) to announce his new book, The South Beach Heart Health Revolution:
The South Beach Diet doctor takes on cardio care

Agatston, the granddaddy of CT heart scanning, is always at least worth listening to. Although his diet may not be perfect, it clearly has jumped light years ahead of conventional diets like the inane American Heart Association diet. The South Beach Diet focuses on healthy oils, nuts, lean meats, vegetables, and fruits, while slashing grains (except in the often disastrous phase III).

The article lists Dr. Agatston's advice to achieve a "heart healthy" lifestyle:


• Maintain a healthy weight through diet.

• Undergo CT heart scans to check for arterial plaque.

• Do aerobic exercise, along with stretching and strengthening workouts.

• Ask your doctor about taking statins and other cholesterol-lowering drugs.


We wouldn't have CT heart scan scoring (at least in its present form) without Dr. Agatston, who developed the algorithm for scoring years ago in the early days of heart scanning. We also need to credit him with putting together a rational diet despite the counter-information emanating from the Heart Association, the USDA (a la Food Pyramid, the one that makes Americans fat and diabetic), and the American Diabetes Association, among others.

But "Ask your doctor about taking statins and other cholesterol-lowering drugs"? This is where Dr. Agatston begins to falter. While he is putting his enormous notoriety to use, his message is bland and ineffective. "Do aerobic exercise"? We don't need Dr. Agatston to tell us this.

As much as Art Agatston has added to the national conversation on heart disease and diet, he has failed to deliver the message of true heart disease prevention. His approach lacks just a few crucial ingredients like lipoprotein testing, diagnosis of hidden causes of heart disease (like Lp(a)), and vitamin D. (Two years ago I had a patient I saw for an opinion after he'd showed Dr. Agatston his lipoprotein panel. The patient said Dr. Agatston looked at the report and didn't know what to do with it and handed it back to him without comment. He then asked if he wanted his autograph.)

Anyway, the rising tide raises all boats. Agatston's repeated public endorsements of heart scans will help deliver the message that heart disease is detectable in its early stages and should trigger action to follow a heart disease prevention program.

That alone is an accomplishment in a world hell-bent on dragging us into the hospital for procedures.

Take this survey: I DOUBLE-DARE YOU

In a previous post I entitled Heart disease reversal a big "No No", I posed a challenge--a dare--to readers to ask their doctors if coronary heart could be reversed.

Here's what I said:

I dare you: Ask your doctor whether coronary heart disease can be reversed.

My prediction is that the answer will be a flat "NO." Or, something like "rarely, in extraordinary cases," kind of like spontaneous cure of cancer.

There are indeed discussions that have developed over the years in the conventional scientific and medical literature about reversal of heart disease, like Dean Ornish's Lifestyle Heart Trial, the REVERSAL Trial of atorvastatin (Lipitor) and the ASTEROID Trial of rosuvastatin (Crestor). Reversal of atherosclerotic plaque in these trials tends to be small in scale and sporadic.

The concept of reversal of heart disease has simply not gained a foothold in the lexicon nor in the thinking of practicing physicians. Heart disease is a relentlessly, unavoidably, and helplessly progressive disease in their way of thinking. Perhaps we can reduce the likelihood of cardiovascular events like heart attack and death with statin drugs and beta blockers. But reverse heart disease? In your dreams!

We need to change this mentality. Heart disease is a reversible phenomenon. Atherosclerosis in other territories like the carotid arteries is also a reversible pheneomenon. Rather than throwing medicines and (ineffective) diets at you (like the ridiculous American Heart Association program), what if your doctor set out from the start not just to reduce events, but to purposefully reduce your heart's plaque? While it might not succeed in everyone, it would certainly change the focus dramatically.

After all, isn't this the theme followed in cancer treatment? If you had a tumor, isn't cure the goal? Would we accept an oncologist's advice to simply reduce the likelihood of death from cancer but ignore the idea of ridding yourself completely of the disease? I don't think so.

Then why accept "event reduction" as a goal in heart disease? We shouldn't have to. Heart disease reversal--elimination--should be the goal.


I know of one person who actually followed through on this challenge and asked his cardiologist whether his heart disease could be reduced or reversed. As predicted, the answer was no. No explanation followed.

But allow me to reiterate: Heart disease is 1) detectable, 2) quantifiable, 3) controllable, and, in many cases 4) reversible.

What if there was a big payoff to your doctor if heart disease was reversed, say $100,000? That's enough to dwarf the payoff from procedures. Guess what? You'd have doctors fighting for your business, a chance to reverse your disease, ads to that effect, champions of reversal emerging. No new tools would be necessary. They could use the tools already available. Then why hasn't this happened? Is the technology unavailable? Are the treatments ineffective?

No, heart disease is a controllable and reversible process with tools that are available today. But there is, of course, no big payoff for doing it. So the financial incentive remains to do procedures, not to reverse the disease.

But I'd like to re-pose this challenge. Ask your doctor if heart disease can be reversed, or at least reduced. I've even posted a Survey at the top left for anyone who tries.

Again, my prediction: Nobody will try it and nobody will post survey results. Why? Despite my rantings (and those of a few others) about the concept of heart disease being a reversible process, in the public's consciousness it remains a death sentence and the only solution is hospital procedures. My colleagues continue to cultivate this attitude and it serves them well financially.

I'll be disappointed if I prove to be right. I hope that I am wrong. But I don't think that I am.



Copyright 2008 William Davis, MD

Michael Pollan on Nutritionism



The wonderfully articulate Michael Pollan has written another book. Although he presents little new to anyone who read his previous book, The Omnivore's Dilemma: A natural history of four meals, he is such a wonderful writer, with such clever ways of seeing the world, that I couldn't resist this new, less ambitious book.

The new book is In Defense of Food: An eater's manifesto.

As in Omnivore's Dilemma, Pollan reminds us that we've lost contact with real food, foods that our great grandmother would recognize, not the just-add-water, dried, pulverized, sweetened, high-fructose, hydrogenated, shrink-wrapped, artificially-colored products that pass as foods in the grocery store.

In particular, Pollan attacks what he calls the ideology of Nutritionism. "The widely shared but unexamined assumption is that the key to understanding food is indeed the nutrient. Put another way: Foods are essentially the sum of their nutrient parts." He calls this "Nutritionism."

In the section called "Nutritionism comes to market," he uses margarine as the prototypical product of this philosophy:

"No idea could be more sympathetic to manufacturers of processed foods, which surely explains why they have been so happy to jump on the nutritionism bandwagon. Indeed, nutritionism supplies the ultimate justification for processing food by implying that with a judicious application of food science, fake foods can be made even more nutritious than the real thing. This of course is the story of margarine, the first important synthetic food to slip into our diet. Margarine started out in the nineteenth century as a cheap and inferior sustitute for butter, but with the emergence of the lipid hypothesis in the 1950s, manufacturers quickly figured out that their product, with some tinkering, could be marketed as better--smarter!--than butter: butter with the bad nutrients removed (cholesterol and saturated fats) and replaced with good nutrients (polyunsaturated fats and then vitamins). Every time margarine was found wanting, the wanted nutrient could simply be added (Vitamin D? Got it now. Vitamin A? Sure, no problem. But of course margarine, being the product not of nature but of human ingenuity, could never be any smarter than the nutritionists dictating its recipe, and the nutritionists turned out to be not nearly as smart as they thought. The food scientists' ingenious method for making healthy vegetable oil solid at room temperature--by blasting it with hydrogen--turned out to produce unhealthy trans fats, fats that we now know are more dangerous than the saturated fats they were designed to replace. Yet the beauty of a processed food like margarine is that it can be endlessly reengineererd to overcome even the most embarrassing about-face in nutritional thinking--including the real wincer that its main ingredient might cause heart attacks and cancer. So now the trans fats are gone, and margarine marches on, unfazed and apparently unkillable. Too bad the same cannot be said of an unknown number of margarine eaters."


Anyone who reads and thinks a lot about nutrition will find little new here. But nobody says it better than Pollan. While Gary Taubes (Good Calories, Bad Calories) is the real thinker of our age about nutrition, Michael Pollan is the true writer about it.

With books like these making the bestsellers list, I believe that we are gradually seeing rationality return to eating. It makes people skeptical of the glitzy ads that run on TV around the clock. I hope that Pollan's new book will make more and more people leery of the latest health claim that adorn some product. "More omega-3!" "A low-fat snack." "Heart Healthy!" "High in healthy fiber!"

Cholesterol follies

Rudy is a 59-year old man. He's had three heart catheterizations, two of which resulted in stent implantations. Obviously, Rudy should be the beneciary of a prevention program.

His basic cholesterol values:

Total cholesterol 164 mg/dl--pretty good, it seems.

LDL cholesterol 111 mg/dl--Wow! Not too bad.

HDL cholesterol 23 mg/dl--Uh oh, that's not too good.

Triglycerides 148 mg/dl--By national (NCEP ATP-III) guidelines, triglycerides of 150 mg/dl and below fall within the desirable range.


So we're left with an apparently isolated low HDL cholesterol, nothing more. On the surface, it doesn't seem all that bad.

Of course, we need to keep in mind that this pattern landed Rudy in the hospital on several occasions and prompted several procedures.

Should we rely on these results? How about Rudy's lipoproteins?

Here they are (NMR; Liposcience):

LDL particle number 2139 nmol/l--Representing an effective LDL of 213--over 100 mg higher than the standard value (above) suggests.

Small LDL particles 2139 nmol/l--In other words, 100% of all Rudy's LDL particles are small. (Thus, weight-based measures of LDL cholesterol fail to tell us that he has too many small particles.)

Large HDL 0 (zero) mg/dl--Rudy has virtually no functional HDL particles.


If we had relied only on Rudy's standard cholesterol values, we would have focused on raising HDL. However, lipoprotein analysis uncovered a smorgasbord of additional severe patterns. The high LDL particle number comprised 100% of small particles is especially concerning.

Truly, conventional cholesterol testing is a fool's game, one that time and again fails to fully uncover or predict risk for heart disease. One look at Rudy's lipoproteins and it becomes immediately obvious: This man is at high risk for heart disease and the causes are clear.

Of course, many physicians and insurance companies argue that the added information provided by this portion of the lipoprotein test added around $70 more to the expense.

When you see results like this, is there even a choice?

Equal calories, different effects

A great study was just published in the Journal of the American College of Cardiology:

Metabolic effects of weight loss on a very-low-carbohydrate diet compared with an isocaloric high-carbohydrate diet in abdominally obese subjects.

88 obese adults with metabolic syndrome were placed on either of two diets:

1) A very low-carbohydrate, high-fat diet (VLCHF): 4% calories from carbohydrates (truly low-carb); 35% protein; 61% fat, of which 20% were saturated. In the first 8 weeks, carbohydrate intake was severely limited to <20 grams per day, then <40 grams per day thereafter.

2) A high-carbohydrate, low-fat diet (HCLF): 46% calories from carbohydrates; 24% protein; 30% total fat, of which <8% were saturated.

Both diets were equal in calories (around 1400 calories per day--rather restrictive) and participants were maintained on the program for six months.

At the end of the six month period, participants on the VLCHF diet lost 26.4 lb, those on the HCLF diet 22.2 lbs (though the difference did not reach statistical significance). Thus, both approaches were spectacularly successful at weight loss.

Surprisingly, blood pressure, blood sugar, insulin and insulin sensitivity (a measure called HOMA) were all improved with both diets equally. Thus, these measures seemed to respond more to weight loss and less to the food composition.

Lipids differed between the two diets, however:


VLCHF:
Total cholesterol: initial 208.4 mg/dl final 207.7 mg/dl

LDL: initial 125 mg/dl final 123 mg/dl

HDL: initial 55 mg/dl final 64.5 mg/dl

Triglycerides: initial 144 mg/dl final 74 mg/dl

Apoprotein B: initial 98 mg/dl final 96 mg/dl


HCLF
Total cholesterol: initial 208.4 mg/dl final 187.5 mg/dl

LDL: initial 126 mg/dl final 108 mg/dl

HDL: initial 51 mg/dl final 54.5 mg/dl

Triglycerides: initial 157.6 mg/dl final 111 mg/dl

Apoprotein B: initial 100 mg/dl final 95 mg/dl


Some interesting differences became apparent:
--The VLCHF diet more effectively reduced triglycerides and raised HDL.
--The HCLF diet more effectively reduced total and LDL.
--There was no difference in Apo B (no statistical difference).

The investigators also made the observation that individual responsiveness to the diets differed substantially. They concluded that both diets appeared to exert no adverse effect on any of the parameters measured, both were approximately equally effective in weight loss with slight advantage with the carbohydrate restricted diet, and that lipid effects were indeed somewhat different.


What lessons can we learn from this study? I would propose/extrapolate several:

When calories are severely restricted, the composition of diet may be less important. However, when calories are not so severely restricted, then composition may assume a larger role. When calories are unrestricted, I would propose that the carbohydrate restriction approach may yield larger effects on weight loss and on lipids when compared to a low-fat diet.

The changes in total cholesterol are virtually meaningless. Part of the reason that it didn't drop with the VLCHF diet is that HDL cholesterol increased. In other words, total cholesterol = LDL + HDL + trig/5. A rise in HDL raises total cholesterol.

Despite no change in Apo B, if NMR lipoprotein analysis had been performed (or other assessment of LDL particle size made), then there would almost certainly have seen a dramatic shift from undesirable small LDL to less harmful large LDL particles on the VLCHF diet, less change on the HCLF diet.

The lack of restriction of saturated fat in the VLCHF that failed to yield adverse effects is interesting. It would be conssistent with the re-analysis of saturated fat as not-the-villain-we thought-it-was put forward by people like Gary Taubes (Good Calories, Bad Calories).

In the Track Your Plaque experience, small LDL is among the most important measures of all for coronary plaque reversal and control. Unfortunately, although this study was well designed and does add to the developing scientific exploration of diet, it doesn't add to our insight into small LDL effects. But if I had to make a choice, I'd choose the low-carbohydrate, high-fat approach for overall benefit.

Is skinny necessary for reversal?

Nothing we do in the Track Your Plaque program guarantees that coronary atherosclerotic plaque or your heart scan score is reduced or reversed.



But everything we do weighs the odds in your favor of successfully achieving reversal: correction of lipoprotein patterns, uncovering hidden patterns like Lp(a), vitamin D, being optimistic--it all tips the scales in your favor.

But how necessary is it to be skinny, meaning somewhere near your ideal weight?

It is important, but not as important as it used to be. Let me explain.

I used to tell people that plaque would not regress unless ideal weight was achieved and all the parameters of abdominal obesity and metabolic syndrome were corrected. This includes blood pressure, blood sugar, low HDL, small LDL, high triglycerides, and high c-reactive protein. Curiously, though, as we've gotten better and better at reducing coronary calcium scores, I've been finding that complete correction of all parameters, including achieving ideal weight, don't seem to be as necessary to achieve plaque reversal.

I almost hate to say this, but I've even witnessed significant drops in heart scan scores in people with body mass indexes (BMI) of 30--obese.

The necessary change doesn't seem to be weight, per se, but the consequences of weight. In other words, if you remain overweight, but blood sugar, HDL, small LDL, etc. have shown substantial improvement, then reversal is still achievable.

Then is it okay to be fat or overweight?

Reducing weight to ideal weight does indeed tip the scales in your favor, since it represents an observable, perceptible measure of all associated patterns. Dropping weight can also minimize the need for efforts to correct the consequences of overweight--you might need less niacin, fish oil, exercise, blood pressure medication, etc. to succeed at plaque reversal. Achieving ideal weight may also provide benefits like reduced risk of cancers and degenerative diseases of the hips and knees. But, to my recent surprise over the last two years, achieving ideal weight is not an absolute requirement to achieve reversal.

This is contrary to what some others say. For instance, in an upcoming interview with Dr. Joel Fuhrman on the Track Your Plaque website, Dr. Fuhrman argues that 10% body fat for males, 22% body fat for females, accelerates plaque and symptom reversal. Dr. Fuhrman is author of Fasting and Eating for Health, Eat to Live, and a new upcoming 2-part book, Eat for Health, and proponent of high-nutrient vegetarian diets and fasting. Dr. Fuhrman has been helpful in teaching us some important lessons on how to apply periodic fasting to accelerate plaque reversal.

So, which is it, fat or skinny?

If given a choice (which everyone has), I'd choose skinny. But, provided all the parameters associated with overweight are corrected, then remaining overweight doesn't necessarily mean that you can't still succeed at plaque reversal.

If you are interested in knowing what your ideal weight is, there are a number of software calculators and tables available, including the HealthCentral.com calculator and the National Heart, Lung, and Blood Institute BMI Calculator.


Image courtesy Wikipedia.

Copyright William Davis, MD 2008

MESA Study: Track Your Plaque-Lite?

The long-awaited data analyses from the Multi-Ethnic Study of Atherosclerosis (MESA) are finally making it to press.

The MESA Study is an enormously ambitious and important study of 6800 people, 45 to 84 years old, that includes white, black, Hispanic, and Chinese participants from six communities around the U.S. (Forsyth County, NC; Northern Manhattan and the Bronx, NY; Baltimore and Baltimore County, Md; St Paul, Minn; Chicago, Ill; and Los Angeles County, California.) Participants had no history of heart disease at enrollment. All underwent a heart scan (either EBT or multi-detector heart scans) at the start. It is therefore the largest prospective study involving heart scans ever performed. It is, not unexpectedly, yielding some fascinating observations relevant to the Track Your Plaque program. The MESA study is, incidentally, funded by the non-commercial, publicly-funded National Heart, Lung, and Blood Institute and is therefore presumably free of commercial bias.

Among the most recent publications is Risk factors for the progression of coronary artery calcification in asymptomatic subjects: Results from the Multi-Ethnic Study of Atherosclerosis (MESA) In this analysis of 5700 of the MESA participants, a repeat heart scan was obtained an average of 2.4 years after the first. Conventional risk factors for heart disease were obtained at the start (see below for details under Measurement of Covariates.)

After analyzing the data and risk factors assessed, such as age, sex, race, blood pressure, body mass index (BMI), presence of diabetes, blood sugar, and family history of heart disease, two questions were asked:

1) What risk factors predict heart scan scores?

2) What risk factors predict progression (i.e., increase) in heart scan scores?

(The second question is particularly relevant to us and the Track Your Plaque experience.)

The MESA analysis showed that essentially all the risk factors assessed correlated with both the initial heart scan score, as well as the rate of progression. No surprises here.

But the most eye-opening finding was that the conventional risk factors assessed explained only 12% of the variation and progression in heart scan scores (coefficient of determination, or R squared, = 0.12.) In other words:

--Conventional risk factors like LDL cholesterol, diabetes, and excess weight explain only a tiny fraction of why someone develops coronary atherosclerotic plaque as represented by a heart scan score.

--The great majority of risk for a high heart scan score remains unexplained by conventional risk factors.

--The great majority of risk for progressive increase in heart scan scores also remains unexplained by conventional risk factors.


In light of the MESA analysis, it's no surprise that strategies like reducing LDL cholesterol with statin drugs fails to prevent most heart attacks. It's no surprise that conventional prevention programs that talk about "knowing your numbers," eating a "balanced" or low-fat diet, etc., fail miserably to prevent the vast majority of heart attacks and heart procedures.

MESA confirms what we've been saying these past few years: If you want control over coronary heart disease, you won't find it in Lipitor, a low-fat diet, and other limited conventional notions of risk. Correction of conventional risk factors like cholesterol and blood pressure are, in a word, a failure. I wouldn't even call the conventional approach Track Your Plaque-Lite. They don't even come close.

If conventional risk factors can explain only 12% of the reason behind heart disease, we've got to look elsewhere to understand why you and I develop this process.



Measurement of Covariates
Information on demographics, smoking, medical conditions, and family history was collected by questionnaire at the initial examination. Height and weight were also measured at the baseline examination, and blood was drawn for measurements, including lipids, inflammation, fasting glucose, fibrinogen, and creatinine. Resting blood pressure was measured 3 times in the seated position, and the average of the last 2 measurements was used in the analysis. Medication use was determined by questionnaire. Additionally, the participant was asked to bring to the clinic containers for all medications used during the 2 weeks before the visit. The interviewer then recorded the name of each medication, the prescribed dose, and frequency of administration from the containers.


Copyright 2008 William Davis,MD
Small LDL particles and increased HbA1c--An evil duo

Small LDL particles and increased HbA1c--An evil duo

Small LDL particles are triggered by consumption of carbohydrates. Eat more "healthy whole grains," for instance, and small LDL particles skyrocket.

Increased hemoglobin A1c, HbA1c, a reflection of the last 60-90 days' blood sugars, is likewise a reflection of carbohydrate consumption. The greater the carbohydrate consumption and/or carbohydrate intolerance, the greater the HbA1c. Most regard a HbA1c of 6.5% or greater diabetes; values of 5.7-6.4% pre-diabetes. However, note that any value of 5.0% or more signifies that the process of glycation is occurring at a faster than normal rate. Recall that endogenous glycation, i.e., glucose modification of proteins, ensues whenever blood sugars increase over the normal range of 90 mg/dl (equivalent to HbA1c of 4.7-5.0%). Glycation is the fundamental process that leads to cataracts, arthritis, and atherosclerosis.

Put the two together--increased quantity of small LDL particles along with HbA1c of 5.0% or higher--and you have a powerful formula for heart disease and coronary plaque growth. This is because small LDL particles are not just smaller; they also have a unique conformation that exposes a (lysine residue-bearing) portion of the apoprotein B molecule contained within that makes small LDL particles uniquely glycation-prone. Compared to large LDL particles, small LDL particles are 8-fold more prone to glycation.

So glycated small LDL particles are present when HbA1c is increased above 5.0%. Small, glycated LDL particles are poorly recognized by the liver receptor that ordinarily picks up and disposes LDL particles, unlike large LDL particles, meaning small LDL particles "live" much longer in the bloodstream, providing more opportunityt to do its evil handiwork. Curiously, small LDL particles are avidly taken up by inflammatory white blood cells that can live in the walls of arteries, where they are oxidized--"glycoxidized"--and add to coronary atherosclerotic plaque.

The key is therefore to tackle both small LDL particles and HbA1c.

Comments (53) -

  • Linda

    10/30/2011 4:00:13 PM |

    What do you consider to be ideal cholesterol readings? I am about to visit a new doctor, a D.O., and I am sure she is going to insist on blood tests for cholesterol plus stress testing, etc. My thyroid TSH was 2.70, but she is already showing reluctance to prescribe any thyroid meds. It is going to be a battle.

  • John Lorscheider

    10/30/2011 4:32:57 PM |

    And it is not just about the wheat either.  It’s all carbs.  Fructose, oats, rice, pasta, potatoes and certain fruits, etc. all drive up HbA1c and small LDL.  Just for a reality check I bought a can of and made a bowl of “properly prepared” Scottish oatmeal yesterday according to Nourishing Traditions.  Those are the minimally processed chewy steel cut oats soaked with warm water and kefir overnight and served with butter and cream.  Yeah, they were good alright, but my fasting BG was 88 and one-hour PP was 158.  A fast 5-mile run and it was back down to 84.  The container is in the garbage can now.  This morning was two pasture raised eggs and bacon with ½ cup of blueberries and Greek yogurt.  Fasting BG 89 and one-hour PP was 88.  My HbA1c went from 5.8 to 5.1 in less than a year and hope to get below 5.0 soon.  The stubborn small LDL percentage dropped during same time period but still have a way to go in that regard.

  • Buddy

    10/30/2011 8:12:20 PM |

    I'm not completely sold on HbA1C < 6.0% being a useful metric for anything but populations.  The problem is that the current HbA1C tests do not control for erythrocyte age and I see wide variations among piers on simialr  grain free lowish carb healthy diets.

    There has been much more research on this effect as it pertains to diabetics that have falsely low HbA1c:  http://www.ncbi.nlm.nih.gov/pubmed/9773739
    http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2581997/

    There is some evidence out there that it works the other way as well, and it makes intuitive sense that the lower inflammation and oxidation associated  with a healthy diet would increase erythrocyte longevity.

    Of course observational studies about any topic (small LDL or HbA1c) are always to be taken with a grain of salt.

  • Rosanne

    10/30/2011 8:30:42 PM |

    I wonder if you have ever experienced with any of you patients  what is going on with my husband?  He has very few small LDL particles, at least according to a VAP test - he is type A with lots of large, fluffy LDL.  But his HbA1c is 6.1.  His fasting glucose is 80, 1 hour post-prandial it's 1685, triglycerides are 60.  This is all on a grain-free, very low-carb Paleo diet.  Do you have any clue what is causing the HbA1c to be elevated?  Could it be anything besides carbs?  He gets lots of exercise and is very fit and lean.  

    Some have suggested that too much protein can also cause elevated HbA1c, due to gluconeogenisis causing higher levels of glucose.  But why would the body make more glucose than it needs?  And why would that excess glucose not show up in his fasting and post-prandial glucose numbers?

    Is there any other factor, besides blood glucose, that can contribute to elevated HbA1c?  No doctor yet has been able to answer this question for us.

  • Rosanne

    10/30/2011 8:32:55 PM |

    Sorry for the typo, his 1 hour post-prandial glucose is 85.

  • Dr. William Davis

    10/30/2011 9:08:02 PM |

    The most common explanation, Rosanne, is that the HbA1c can stay high long after blood sugars have come under control.

    It may be due to the extended longevity of RBCs that occurs in the setting of low-carbohydrate diets that allow a previously high HbA1c to stay high for an extended period.

    There's also the possibility of a hemoglobin variant that allows this.

    I would put more stock in the blood glucose values by fingerstick than the HbA1c.

  • arlene

    10/31/2011 12:42:56 AM |

    Thank you for explaining this.  I just had my blood work done for the first time since quitting wheat and going low carb in April.  Since I've lost a lot of weight, and a lot on my waist, I am very curious to see what my numbers are.  This will help me compare the important stats.  What is an ideal HbA1c?

  • pjnoir

    10/31/2011 7:37:40 PM |

    I can't go near oatmeal, steel cut or any other type.  Its just eggs and avocados for breakfast these days with a lot of Asparagus in the spring with my yolks.  Oatmeal has been banished for good.

  • Bob Sparkes

    10/31/2011 10:46:27 PM |

    Your article discuses how the combination of small LDL particles  and high blood sugar
    results in plaque. Is the article cited below  by University of Washington at St. Louis useful here? The article points out the role of low Vitamin D in plaque formation with LDL  and high blood sugar. Or am I confusing two separate mechanisms in plaque formation.

    http://news.wustl.edu/news/Pages/14489.aspx

  • Dr. William Davis

    11/1/2011 2:01:29 AM |

    Hi, Bob--

    Yes, I believe it is two unrelated mechanisms. However, this is a fascinating finding to tell us why people do so well from a heart standpoint when we correct vitamin D deficiency.

  • learn chinese

    11/1/2011 4:05:55 AM |

    Thank you for explaining the topic. i learn more about Small LDL. great post.

  • Jeanne

    11/1/2011 5:36:29 AM |

    Dr. D,  
    Can this be related to the lysine- arginine balance in the body? Would taking arginine supplements affect the amount of lysine residue causing problems in any way?  Just thinking out loud ...

    Thanks!

    Jeanne

  • Amit

    11/1/2011 8:01:31 AM |

    HI Doctor Davis,

    I know its not the right place, but I could not find your email.

    I read "wheat belly", it was revolutionary for me,  and I am persuaded it can bring much relieve to many ailments.

    I also wrote several posts about this issue on my health blog (in Hebrew)  based on your book and your Blog.

    Thank you for the great service you are offering in your work!

    Amit.
    Israel.

  • Janis

    11/1/2011 2:40:01 PM |

    Hello Dr. Davis,
    I'm new to your blog. Just finished reading Wheat Belly. Excellent book! I also listened to the podcast with Robb Wolf. That's how I heard about you. Not to get off topic (didn't know how else to contact you) and this is probably a silly question, but would like clarification if you could help. I've been purchasing the 85% Lindt chocolate bars until you mentioned that you eat the 90%. I read the label and it said that it is pressed with alkali. You mentioned to avoid this process as it removes the healthful flavonoids. By saying "pressed" is that a different process? The chocolate was very good, but I want to make sure I'm getting the healthful flavonoids, especially when we don't eat too many sweets. Thank you so much for your time.

  • Might-o'chondri-AL

    11/1/2011 6:44:50 PM |

    Hi Dr.,
    I am confused how to  reconcile  HbA1c details  from J Am Coll Nutrition 2005, Vol.24(1):22-29
    "Dietary Carbohydrate and Glycated Protein in the Blood in Non-Diabetic Subjects"
    http://www.jacn.org/content/24/1/22.full
    (and their relevant references no. 10 -  19 & 34-39 )

  • Rosanne

    11/1/2011 7:15:17 PM |

    This has been going on for 2 1/2 years and in fact, the longer he has been low-carb Paleo, the higher the HbA1c has gotten.  When he started, it was 5.5 and has slowly
    crept up to the 6.1 reading.
    Thanks for the mention of the hemoglobin variant, I guess that's must be it.  Can we stop worrying about the HbA1c since his glucose values are so good?

  • STG

    11/1/2011 7:34:13 PM |

    Dr. Davis:
    What do you you think of Jenny Ruhl's advocacy of the 5% club at Blood Sugar 101? Your guidelines appear to be more aligned with Dr. Bernstein's and Dr. Ron Rosedale's? Do you think that all individuals ( including prediabetics, daibetics and glucose intolerant ) should strive for a HbA1c below 5%?

  • Dr. William Davis

    11/2/2011 1:36:45 AM |

    HI, STG--

    That is precisely what I aim for, also: HbA1c of 5.0% or less. At that level, metabolic consequences of blood sugar essentially disappear. This is, of course, at variance with conventional guidelines.

  • Dr. William Davis

    11/2/2011 1:37:19 AM |

    That would be my vote. Ask your doctor, also, about fructosamine, another sugar markers.

  • Dr. William Davis

    11/2/2011 1:39:24 AM |

    Hi, Might--

    Were you referring to their conclusion about polyunsaturates?

  • Dr. William Davis

    11/2/2011 1:42:08 AM |

    My bar says "processed" so, yes, the flavonoid content can be expected to be reduced in this bar. The best way to get a full dose of cocoa flavonoids is in undutched cocoa powder.

    I still think you can enjoy your dark chocolate, but you just might not expect full benefit from this particular bar.

  • Dr. William Davis

    11/2/2011 1:44:08 AM |

    Thank you, Amit!

    What is the wheat situation in Israel? Is it pushed there as much as it is here by official agencies and food companies?

  • Dr. William Davis

    11/2/2011 1:44:43 AM |

    Sorry, Jeanne, I don't believe the answer is known.

  • Might-o'chondri-AL

    11/2/2011 3:35:43 AM |

    Hi Dr. D.,
    Authors in this report say glycated protein & HbA1c do not interact  with blood glucose in same way (ref #17) and that it is glycated albumen rather than glycated hemoglobin that is very senstitve to blood glucose levels (ref # 18,19); especially since 60% HgA1c is genetic (ref #61).
    AGE (advance glycation endproducts) they say is more indicated by fructosamine level from high blood glucose. Although diabetics with high fructosamine also have high HbA1c. whereas for a non-diabetic  high fructosamine does not relate to their HbA1c level (ref#16).
    This impies that (since most obese individuals never will become diabetic &  longevity/cognitive function of the overweight is good) a lot of the risk factor of small LDL with HbA1c depends on genetics/ epigenetics.
    My confusion is if your insistence on HbA1c for non-diabetics is misdirected or just due to it being a common first test people can do.

  • Amit

    11/2/2011 5:15:45 AM |

    Wheat is the most common carbohydrate in Israel. It is eaten almost every meal. I think that the largest source of calories is wheat.

    Regarding Diabetes there is no awareness that whole wheat is especially bad for such patients. Diabetes association (and many more) do recommend whole wheat. Although they are suggesting to avoid eating large quantity of bread at once.

    Wheat is being pushed, though, I don't think that somebody here is pushing wheat deliberately, just coping recommendation from abroad, and using the most cheap and easy carbohydrate.

    Amit.

  • Nora

    11/2/2011 12:10:50 PM |

    I have been on my Wheat Bellies journey for 8  weeks now.  I am trying to follow your suggestions on heart health and I know that you have your plate full right now, but just a request.  Have you ever thought of doing healthy heart retreats?  I would love to have a chance to go away for a long weekend, have all my blood work done right, have it evaluated, talk to a doctor and then maybe have a few cooking classes.  Throw in a few yoga classes or walks for stress reduction and you have a whole picture!!  

    I have high blood pressure that is 'controlled' to some degree with Tekturna (150mg) and Amlodipine (10mg). This morning it was 150/90, so it is often not very controlled. Since 9/1 and going wheat free, I have lost 23 pounds but still have 50 to lose.  My take away from your writings is that plaque is the  main cause of heart disease and that keeping a low blood glucose level is the best strategy, but there is not much about  high blood pressure in your work.  What role does it play and will being a wheat free low carber offer me relief from my high blood pressure?  Or will it stay high since I have a family history of high blood pressure and therefore will probably have to continue on my meds.  While I, of course, am doing everything in my power to lower my blood pressure, is it not really a number I should focus on when trying to control my heart health?

  • Renfrew

    11/2/2011 9:08:47 PM |

    Hi Doc,
    have you seen this? You are prominently featured here:
    http://www.lef.org/news/LefDailyNews.htm?NewsID=11842&Section=Nutrition
    Great summary!

  • marta

    11/4/2011 9:48:08 AM |

    Are you going to translate his books into Spanish some day?
    I'm very interested in reading them. thanks

  • Dr. William Davis

    11/4/2011 12:48:56 PM |

    Hi, Marta--

    There has been interest specifically in Wheat Belly for translations. Spanish is at the top of the list.

    When that happens, I will announce here and elsewhere. Thanks for asking.

  • Dr. William Davis

    11/4/2011 12:50:33 PM |

    Thanks, Renfrew!

    Life Extension has been an important supporter of my efforts and vice versa.

  • Dr. William Davis

    11/4/2011 12:53:43 PM |

    Hi, Nora--

    Excellent suggestion on the heart health retreats. I've thought a lot about it and will likely do it in future. Just not quite sure about the details. One hurdle: Few people want to fly to Milwaukee, so we'd have to find an exotic or interesting, probably warm, place to do it.

    Hypertension is indeed a big issue. It is also among the last things to respond to weight loss and diet, often lagging behind many months after weight loss. So it really pays to be patient while you are on this health journey. Given your family history, you still might be left with hypertension, but at least you will have minimized it.

  • Dr. William Davis

    11/4/2011 12:54:43 PM |

    Thanks, Amit.

    By the way, all anyone has to do is check a fingerstick blood sugar 1-hour after consuming anything wheat to observe the astounding blood sugar consequences of wheat consumption.

  • Dr. William Davis

    11/4/2011 12:58:54 PM |

    Hmmm. I'm sorry if I'm being dense, Might, but I'm still not sure I follow.

    I'm not actually advocating anything except to show how glycated small LDL is a really bad player. When viewed from multiple different directions, small LDL particles are looking worse and worse. In this instance, having any measure of glycation phenomena, whether fructosamine, glycated albumin, or glycated hemoglobin, suggests that small LDL particles are also being glycated and thereby gaining heightened atherogenic potential.

  • Sally

    11/4/2011 2:02:44 PM |

    Dear Dr. Davis,

    I am reading your book Wheat Belly and want to thank you so much for writing this book.

    I've avoided gluten for years.  Arthritis and other annoying symptoms vanished...but I started gaining weight!   My blood sugar starting rising!   I couldn't understand it!  It was horrifying!  Well thanks to you, I realize that gluten free breads, candies, flours,  frozen pizzas, pastas and those gluten free "tv dinners" sold at Whole Foods did nothing to help my waist line or blood sugar.  I am now following the wonderfully easy plan in your book and am confident the weight will come off.

    Thank you for such terrific recipes.  Will you be writing an accompanying Wheat Belly cookbook as well?  I certainly hope so.  Please do!   If not, can you recommend some cookbooks that comply with your eating instructions?

    Thanks again for such a life changing book.  Sally

  • HS4

    11/4/2011 9:09:05 PM |

    There are a few people in Israel trying to enlighten others about the dangers of wheat and other 'modern' carbs.  My sister is one of them, has been trying to think of ways to get some essays to the public.  But what Amit says is correct - a lot of wheat is eaten there, many people buy small breads  rolls daily - it's very fresh, delicious, so it will be a tough thing to stop. Many of the best restaurants in Israel serve Arabic food which always comes with freshly baked loaves of pita.  The 'national snack' is pita stuffed with falafel (fried balls of ground chickpeas, onions, garlic and spices), fresh & pickled vegetablesj, hummus and/or tehina sauce. This is available everywhere and always fresh.  Becasue the food is generally very good in Israel and also very fresh it's hard to avoid wheat, which I've noticed every time I visit.

  • palo

    11/5/2011 5:07:43 PM |

    Dr. Davis, the evidence speaks for itself that consumption of carbohydrates, increase small LDL, suggesting an LC diet of less than 50 grams to mitigate the damage.
    But what about endurance athletes (runners, cyclists, triathletes etc.) that work out one and a half to three hours per day and consume copious amounts of carbohydrate to fuel their long workouts.
    Is the exercise neutralizing the carbohydrates' harmful effects? If so, can you suggest a dosage for certain amount of exercise?

  • Might-o'chondri-AL

    11/6/2011 8:26:57 PM |

    Hi Dr. Davis,
    Non-diabetics just seem to have one feature going for them - their platelets don't respond the same as diabetics. I am inclined to think that albumin in our blood is more relevant than the hemoglobin being glycated . (This is not to criticize your preventative approach , since Type II diabetes can go on to develop &  I like what you are teaching us about small LDL.)

    " One common qualitative change in plasma albumin is nonenzymatic glycosylation, which occurs during states of prolonged hyperglycemia....Platelet aggregation ...is enhanced in the presence of albumin that has been incubated in a medium containing levels of glucose that are higher than would be seen in normal patients but are consistent with those seen in diabetics....(Journal of Parenteral and Enteral Nutrition 18:516-520, 1994)

    Once the glycation of albumin fosters more platelet aggregation in diabetics (& the insulin resistant person!) their platelets show more secretion and adhesion leading to the vascular plaque build up that the insidious small LDL can get into. Yet, for the non-diabetic the +/- 570 insulin receptors on each platelet normally respond differently to their insulin exposure.

    Specifically (in non-diabetics) the insulin actually stymies the platelet from becoming "activated" and probably explains how it is that not everyone who eats carbohydrates suffers cardio-vascular insults. Of course there are non-diabetics with genetic variants that adversely affect their plaque dynamics (ex: defect in insulin receptor signalling, that receptor's Beta subunit, G-protein pathways).

    ( For the techno-nerds: proper insulin receptor response on platelet keeps  platelet cAMP level from dropping & so no endoplasmic reticulum calcium floods out into platelet cell cytosol, platelet granule doesn't secrete ATP, platelet alpha-granule doesn't secrete P-selectin & there isn't mitogen-activated signalling to make thromboxane A2 , etc.  Basically, in the diabetic/insulin resistant these processes go forward uninhibited by normal insulin signalling & their circulating platelets don't keep rolling along suspended in the bloodstream .)

  • Adam

    11/7/2011 5:27:55 PM |

    Omega 3 Fish Oil BAD NEWS for Apoe 4/3!!!  

    Ok Dr. Davis, I really need your advice on this one.   In following TYP, I have been taking 3200 mg day EPA/DHA fish oil 1.4:1 ratio.   Recent testing shows I have gotten my HS Omega 3 Index to 9.5,  and my Omega 6 to Omega 3 ratio to 2:9  so this pretty good.   Now for the bad news....ever since I started taking 3200 mg day fish oil...over a 2 month period my HDL went from 48 to 38, a whopping 20% reduction in the critically important good HDL that I need to remove plaque.  I exercise extensively, and I also take 10mg day crestor (crestor is one of the few statins that's supposed to raise HDL not lower it). Now,  I have heard from several sources that Fish Oil (more than 1000 mg day) supplements are actually BAD for Apoe4/3 people because it lowers HDL.  So now I am confused Dr. Davis.....do I follow your TYP advise and stay on 3200 mg day fish oil in order to keep a close to 10 HS Omega 3 Index....but suffer lower HDL and less plaque removal/reversal....or do I stop the Fish oil in order to raise my HDL  but suffer the risks of little to no fish oil??

    Please advise...

    An extremely confused Apoe 4/3

  • Might-o'chondri-AL

    11/7/2011 11:02:03 PM |

    Hi Adam,
    HDL drop can be due to accelerated small HDL's  breakdown/clearance & if that was mostly lingering small HDL then it didn't have much reverse cholesterol transport function left in it anyway. If total HDL drops but small HDL turnover is  now more optimal &/or if it is a greater % of the large HDL then there is better reverse cholesterol transport dynamic despite the total HDL drop.

    ApoE has 299 distinct amino acid positions & the difference between the 3 types are due to which amino acid is in positions 112 & 158 ( respectively ApoE4 @112=arginine & @158 =arginine, ApoE3 @112=cysteine & @158=arginine, ApoE2 @112=cysteine & @158=cysteine). Because ApoE4 has arginine at position 112 this then orientates facing away from the standard grouping of 4 helix at that N-terminal to more closely cozy up to the alpha-helix of the C-terminal that in ApoE naturally overlays the N-terminal. Thus ApoE4 can uniquely feature a "salt bridge" to that C-terminal that affects how ApoE unfolds/functions when ApoE goes to work.
    ApoE's manner of unfolding at it's N-terminal  is crucial to how it deals with lipids, phospholipids (ex: cell membranes)and  proteoglycans on a cell surface. Fish oil alters cell membrane phospholipid composition and then the proteoglycans there must suitably interact with that EPA enriched type of cell surface. Since each ApoE's C-terminal presents an interface that challenges  how that ApoE  works at any target cell the  peculiar ApoE4 "salt bridge" uniquely conditions the way interactions play out. (And each of the separate 3 classic types of ApoE  can get mutations, mostly at positions 136-150, to complicate degree of LDL receptor interaction, etc.)

  • James Buch

    11/8/2011 3:14:01 PM |

    Dear Doctor Davis,

    I am wondering if you can clarify the "oxidized LDL Cholesterol" concept.  Including, of course the Small LDL as well.

    I began wondering if the oxidation is primarily in the package, the LDL wrap, the signaling protein, or the internal body of cholesterol itself. Of course, all of the above is also a possibility.

    The nature of the oxidation could be a good clue as to how it is especially detrimental to health, and so far, I haven't found much easily available on the mechanisms of the detrimental effects. While it is useful to know the harmful nature of oxidized small LDL, some insight into the mechanism of harmful effects would be welcome and minimize the nagging question of "Why" for me.

  • josef

    11/8/2011 5:07:20 PM |

    This might be of interest:

    A large study called the STRRIDE trial looked at the effects of different intensities and volumes of exercise on LDL particle size in sedentary, overweight men and women over eight months [3].  Group A performed 176 minutes of low intensity exercise (walking) per week.  Group B performed 117 minutes per week at a moderate to high intensity (jogging, cycling, or using an elliptical machine).  Group C exercised about the same amount of weekly time as group A, but at the same intensity as group B.  

    As one would likely guess, group C showed the biggest improvement in changing LDLs from small and dense to large and buoyant.  However, a more telling sign was that group B had a stronger effect than group A, despite exercising an hour less per week.  In other words, intensity is more important for improving LDL particle size than volume of exercise.

    A follow-up of the subjects in this study showed some discouraging and encouraging effects on the particle size changes [4].  The discouraging news was that five days of inactivity following the study almost completely attenuated the particle size benefits from the trial.  However, before you start labeling exercise as futile, consider this: while five days of rest basically brought the exercise groups back to baseline LDL particle sizes, they were still much better off than the sedentary control group, who experienced significant digressions in particle size during the course of this study

  • Might-o'chondri-AL

    11/8/2011 7:18:31 PM |

    Hi James Buch,
    The enzyme hepatic lipase's (HL) lipolytic hydrolysis of the phospho-lipids on the LDL surface changes it so that LDL's load of cholesterol esters can get taken out; this reduces the molecule's volume and thus is then small LDL (smLDL). Men have more HL than women, until they go through  menopause, and this propensity toward smLDL ( that can get oxidized) may explain male's earlier tendency of coronary artery disease. Visceral/central obesity trends to upregulate HL & it seems visceral obesity affects men more than women (of course central obesity in both women & men will raise both  genders'  HL enzyme levels). What decreases HL levels are things like calorie restriction & aerobic exercise (sedentary life increases HL).

    Doc harps on avoiding elevated triglycerides after meals that load triglycerides into VLDL  molecules because the enzyme cholesterol ester transfer proetein (CETP) shunts triglycerides from VLDL (& chylomicrons) over to the standard circulating "big bouyant" (large & fluffy) LDL and fosters transfer of cholesterol out of that LDL; the triglyceride takes up less space and thus get smLDL.
    Central obesity usually correlates with elevated triglycerides and increased HL levels. However, if triglyceride genetics (or epigentics from Doc's diet ,etc.)  in the obese without that usual accompanying high triglycerides then that upregulated HL doesn't cause a lot of that individual's standard "big bouyant" LDL to become smLDL. HL also hydrolysizes triglycerides (and phospho-lipids) of chylomicrons, BetaVLDL, IDL, LDL & HDL. Both CETP & HL enzymes being elevated alone, or together, can provoke smLDL - genetic polymorphisms exist for both enzymes.

    sm LDL has less antioxidants left yet it's surface has higher ratio of poly-unsaturated acids which make it's phospho-lipids more at risk of oxidation. And smLDL has less sialic acid left on it's surface which fosters more poly-anion proteoglycan binding that increases the smLDL molecule's transportability across the endothelial lining into the artery wall .
    Doc harps on need for Magnesium because in real time magnesium is what interrupts the oxidation of smLDL from locking into an altered state & then salvaged plain old smLDL doesn't get to go on to be so damaging.

  • Might-o'chondri-AL

    11/9/2011 3:24:05 AM |

    Continued for J. Buch,
    Oxidized small LDL (oxLDL)  has fragments from it's oxidized PUFA (poly-unsaturated fatty acid) that are reactive aldehydes (ex: malon-di-aldehyde & 4-hydroxynoneal-lysine) which then fragment that smLDL's  lipoprotein ApoB.  That peroxidation of a PUFA acyl chain of  the smLDL phospholipid  leaves a type of carboxyl portion that the beta-2-glyco-protein I (Apo H) binds to using a "reactive" ketone as ligand link. Thus it is the position of the "reactive" ketone (keto-cholesteryl-9-carboxy-nonanoate) on the involved cholesterol molecule's spine that determines the % of glyco-protein bonding that occurs (genetics influences ketone placement on a human cholesterol molecule).

    Magnesium (Mg++) in the very early stage of glycated protein (Doc warns against advanced glycation end products) hooking up with LDL reverses the glyco-protein link to the "reactive" ketone. But if deficient Mg allows time to consolidate that contact then only a physiologiclly abnormally high pH will let Mg re-break that bonding.

    Immunological T cells respond (with age & gender differences)  to try to get oxLDL off the artery wall;  and, if there is too much to handle there is the risk of developing a so-called oxidized LDL-containing Immune Complex (oxLDL-IC). And this oxLDL-IC provokes cytokines that perpetuate the inflammation response. Over time and older age there is  less output of a malon-di-aldehyde oxLDL  immune response; which is possibly what leads to long established plaque having less lipid component and more involvement of collagen. It is relatively younger plaque that is unstable and more likely to rupture; the collagen draws in more Calcium and unfortunately provokes artery hardening problems.

    Now the lipid part from this oxLDL-IC gets into an immunological monocyte cell's endosome  and the ApoB gets into that same monocytes lysosome - sub-compartments inside the cytosol (cell interior). Then the lipid part in the endosome triggers heat shock protein (HSP 70/70B) which wrenches things so that the lysosome can't get to work on the lipid and ApoB prevents the lysosome from doing proper interactions at the inside of that cell's membrane to expel  the burdens. Once oxLDL cholesterol esters bulk  up a macrophage (monocyte) due to increasingly futile lysosome  activity  it becomes the notorious "foam" cell. Eventually that macrophage cell dies and the whole load get's polymerized into plaque.

  • Might-o'chondri-AL

    11/9/2011 8:03:57 PM |

    Hi Dr. Davis - with your indulgence:
    Back to platelets( see above Nov. 7): vascular remodeling with age &/or ROS exposes a bit of phosphatidyl serine  that platelets can "snag" onto as platelets flow along. Key to accomplish platelet snagging is signaling by  the promoter P2gamma12 and normally insulin signaling down inhibits P2gamma12. But, notably for Type II diabetics (and assumedly proportional to an individual's insulin resistance) their insulin doesn't inhibit that snag signal. Type II diabetics also have P2gamma12 upregulated in their platelets. And if anyone is of P2gamma12  haplo-type H2 those individuals will have even more of the receptors for it and therefore an  increased risk of peripheral artery disease. Irregardless of haplo-type, the Type II diabetic's propensity for peripheral artery problems are compounded by  their basal level of excess P2gamma12 .

    Adhesion to the artery then physically involves the platelet surface Glyco-protein Ib & vonWillebrand factor hitched to collagen provoking Integrin 2beta1 (GPVI) so the platelet/collagen sets in place. If the level of promoter P2gamma12 in that challenged site is fortuitously low then the rate of adhesion to the blood vessel is poor. So, predictably, for Type II diabetics the adhesion rate (like platelet secretion & aggregation) is higher than normal. GPVI insult also signals a release of ADP & this ADP (like collagen itself) independently induces aggregation of platelets; the plaque recruits to build itself up to be more fibrous. The plaque matrix serves as nesting for oxLDL & dying macrophage foam cells to polymerize with.

    ROS remodeling agents of the vasculature come from mitochondrial activity and  it appears certain (overlooked) relevant gene pheno-types (and their respective polymorphisms) can be pro-plaque (or preventative) - speaking here in the sense of  a primal influence on plaque risk as well as  tendency of the actual amount of plaque. Sirtuin 5 (Sirt5), a mitochondrial Sirt (there are nuclear Sirt too) binds to Uncoupling Protein 5 (UCP5) and governs that (& other) UCP. Sirt (there are 6 types) remodels chromatin (DNA spooled around a histone ) via histone de-acetylase enzyme; while our UCP (there are 5 types) work in the inner mitochondrial membrane governing the proton electro-chemical gradient that is integral to the chain of oxidative phosphorylation (a way to generate ATP, among other functions).

    Sirt action on DNA includes (among other dynamics) the cellular level encoding of how individual fatty acid metabolism fine tunes -  lipid fatty acids included.Sirt action on DNA includes (among other dynamics) the cellular level encoding of how individual fatty acid metabolism fine tunes -  lipid fatty acids included. Doc's diet/protocol may ( I suggest) sometimes  tweak out favorable health response(s) via induced epigenetics, because of remodeling that is induced in the chromation DNA unit packaging . Sirt's histone de-acetylase working depends on NAD- to drive Sirt and Doc's diet/protocol theoretically seems to be capable of altering NAD flow patterns from his weaning of cells'  mitochondria off of glucose.

    UCP5  rules the inner mitochondrial membrane potential & the rate of oxygen use, which can become relevant to ROS levels. Both UCP5 and Sirt5 are upregulated in hypertension and Type II diabetics; the confluence of having geneticly more UCP5 along with Sirt5 are implicated in increased carotid artery plaque. (Of course nothing is linear in humans so haplo-type T- carrier UCP5 polymorphism rs5977238 benefit with less plaque risk and reduced plaque numbers.) Note: I am skipping over other Sirt & UCP; but will add that lots of pheno-typic UCP1 spins out extra amounts of reactive super oxide to drive down nitric oxide and implicated in accelerated aging of the vasculature.

  • Jack Kronk

    11/10/2011 8:13:40 PM |

    Might/Doc - Does this mean that if you DONT have proper insulin receptor response that all of the things listed in the last paragraph become untrue? (meaning bad?)

    Would this mean that you are implying a low carb diet would be the best solution due to the insulin issues?

    I ask because I cannot raise my HDL for the life of me. It is completely stalled at 40. And my LDL is primarily small dense kind. I have only really had this problem since going "LC Paleo" and adding a ton of sat fat to my diet but then I added back in starches and other carbs and became more moderate carb, while still continuing to eat bacon/eggs/cheese/cream/butter/beef/coconut oil/ghee/nuts etc.

    Now I've got people telling me to go back to LC, and exactly the reverse, people telling me that I need to cut out the fats including dairy and go low sat fat.

  • STG

    11/10/2011 11:18:15 PM |

    Mito....:
    I have viewed your comments at the Hyperlipid and always appreciate your detailed biochemical/physiological explanations per topic. Your grasp of details and mechanisms is amazing! What is your background? Are you a biochemist by trade?

  • Kent

    11/11/2011 4:34:12 PM |

    A retreat is an excellent idea!  It would be a great time of learning and discussions. I vote for Gulf Shores Alabama Smile

  • Might-o'chondri-AL

    11/11/2011 7:02:07 PM |

    HI STG,
    My hope here is that I never hijack Dr. Davis'  blog ( I never personally posted on Hyperlipid blog).  I trust  Doc's readers know he is not responsible for any errors I make. Being semi-retired from consulting on agro-industrial projects in developing countries I feed my mind by keeping up with health science & commenting here about correlations to Doc's work.

  • Might-o'chondri-AL

    11/12/2011 9:33:23 AM |

    Hi J. Kronk,
    Saw your 11 Nov. query &  feel diet advice here is for Doc to offer (not me). Doc discusses ApoE pheno-types he restricts dietary fat for. You "tagged" me where I  was elaborating on platelets' interaction with insulin & how insulin resistance is a game changer (not sure what confusing).

    If one is insulin resistant then the signaling to build-up (anabolism) from insulin is selectively diminished and consequently break-down (catabolism) signals get  into play. Proteo-lysis is protein cleaving and HDL's protein component can be more rapidly subject to proteo-lysis; which I presume (?) is why/how some people degrade their HDL so quickly. Genetic quirks (& gender) also hit HDL levels notably;  yet  if quick enough turnover the "stale" HDL  might be being replaced by more functional HDL. According to the "HATS" study HDL alone is not a predictor of coronary artery disease mortality.

    Niacin usually decreases rate of catabolism of HDL,  it helps secrete more ApoA1 to make into HDL & decreases amount of  smLDL. Niacin isn't perfect since it alters the extent to which HL (hepatic lipase enzyme) can work on a  HDL molecule to morph  it into the kind of HDL that has the maximum reverse cholesterol transport capability. HL is what hydrolyses the triglycerides in HDL - so, basicly if HDL loaded with trigs it has sparser room for scavenging cholesterol.


    One's genetic response to increased levels of circulating palmitate free fatty acid can interfere with insulin signalling in the liver. Whether clinically insulin resistant or due to a genetic quirk (you?),  palmitate can phosphorylate liver insulin receptors in a manner unlike "normal" individuals do in the Akt process (insulin normally should get Akt going to stop liver gluco-neo-genesis - since insulin has glucose to drive into cells ). Essentially "excess" palmitate, in this example, is causing only a partial phosphorylation of Akt & is how researchers can use very high fat diets to induce experimental diabetes .

    I don't hear you being insulin resistant, so address genetics of Protein Phosphatase 2A (PP2A), which  has components involved in it's regulation and is subject to different structure. How PP2A parts interact with distinct parts of the Akt molecule can  impair some interactions,  yet leave other parts of Akt responsive ( to do what Akt  is normally designed to do). Palmitate can raise PP2A levels in the liver by 30%; so basically the more PP2A  around and/or the molecule's genetic tweaks the weaker a key part of  the liver's Akt response is going to be.

    Since palmitate  being in the liver does not stop insulin there from fostering more trigs there are still post-prandial trigs going into the VLDL . In other words the liver insulin resistance and rogue genetics can leave the part of Akt that governs lipo-genesis still responsive to insulin. Doc warns us about trig enriched VLDL & chylomicrons promptly driving  smLDL that doesn't degrade & small particle numbers measure high; he is more adamant about post-prandial trigs but genetic high overnight trigs can occur.

    I don't think coconut oil acts the same way high animal fat sometimes does on Akt . We internally make palmitate when acetyl-CoA acted on by enzyme acetyl CoA carboxylase  to make malonyl-CoA that fatty acid synthase converts to palmitate. I think most of coconut oil's fatty acids are metabolized before getting into that pathway so maybe coconut oil is worth parsing when genetics or insulin resistance drives up smLDL.

  • STG

    11/12/2011 6:16:07 PM |

    Mito..
    Excuse my error about you posting on the Hyperlipid. I guess I have read your posts elsewhere. In any case, your posts are very educational and explain precisely the biochemistry  Thanks for sharing your knowledge!

  • Mark

    8/14/2012 3:24:54 AM |

    Hi Dr. Davis,
    I’m 47 yrs old. I’ve had migraines since I was a teen and I developed Athsma this past January (hate it). During the process of discovery the drs found I have a 50% blockage in one of the 5, non critical, arteries running along the back of my heart. Scared me, to say the least. I’ve always eaten quite healthfully (for what I knew), am thin @ 6′ 1″/155lbs (was 175lbs in Jan.). Had total cholesterol of 200/LDL of 146/HDL of 50. Drs wanted me to do Lipitor. Researched and said, “No, thanks.” Started exercising 5-6 days/wk (lifting + walk/run), taking red yeast rice, fish oils, fish, no meat, no dairy, no eggs, lots of veggies/fruit, etc., but still eat beans, oats (every AM), occasional wraps. After 6 wks my blood work (VAP) was as follows: LDL=86, HDL=43, VLDL=17, TOT. CHOL=146, Trigycerides=66, Non-HDL (LDL+VLDL)=103.

    Seemed GREAT to me! The dr wasn’t impressed. Said my ‘particle size’ was small: LDL1(a)=8.1, LDL2(a)=0, LDL3(b)=39.5, LDL4(b)=24.9. Density Pattern=B.

    I’ve continued but don’t know how to elevate my HDL and reduce the particle size/change the pattern to the more favorable ‘A’. Getting down about this. Working hard but, seems like I can’t find answers that work, anywhere! What might you would work in my situation? Also, Is niacin ANDRed Yeast Rice a bad idea?
    I’ll hang up and listen. Thank you,
    Mark

    PS - I left this post on another page, as well.

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