All posts by william-davis

What to eat: Part I

6. April 2010 William Davis (0)

I've spent a good number of Heart Scan Blog posts detailing what foods to limit or avoid.

The list of unquestionably bad foods to avoid include foods made of wheat, cornstarch, and sugars. Fructose is proving to be an exceptionally bad form of sugar, worse than any other. I've issued warnings about levels of carbohydrates that can be determined by postprandial testing.

In response to several requests to clarify what foods to eat, this post begins a series discussing what foods are good to eat.

I believe that a strong case can be made for eating vegetables in nearly all its varied forms, from cucumbers to peppers to leafy vegetables to eggplant to alliums like onions. The only form we avoid are red and white potatoes due to the blood sugar-increasing effects.

While this seems obvious, I am impressed how many people who follow low-carb diets find themselves following a high-animal product diet with vegetables as the sideline. It should be the other way around: A high vegetable diet with animal products as the sideline.

Vegetables are your principal source of:

1) Flavonoids and polyphenols--e.g., anthocyanins and catechins. All the recently appreciated effects of flavonoids and polyphenols highlight the wonderful effects of compounds originating in plant foods. This includes the anthocyanins and resveratrol in red wine; the catechins and epicatechins cocoa and green tea; the hydroxytyrosol, phenolic acid, and flavonoids of olive oil.

2) Fiber--Fiber is essentially a plant phenomenon, since there is virtually none in chicken, fish, and beef. The benefits of fiber are, I believe, undisputed. Neglecting fiber can, at the very least, lead to a nasty case of hemorrhoids. At the worst, it is related to various cancers, especially colon cancer.

3) Vitamin C--While vitamin C may be old and boring in light of new, exciting discoveries like flavonoids, neglect leads to bad things.

Vegetables are generally classified as carbohydrate foods, since they are low in protein and fat. But this is the source of carbohydrates you do not want to sacrifice in a low-carbohydrate diet. There's just too much good from vegetables.

Notice that I didn't say "fruits and vegetables." This is a fundamental mistake made by many: Oveconsumption of fruits. I've even seen people who follow an otherwise good diet develop diabetes--just from too much fruit.

Vegetables should be the cornerstone of the human diet. But I'll bet you knew that already.

Carbohydrates and LDL

4. April 2010 William Davis (16)

There's a curious and powerful relationship between carbohydrates and LDL particles. Understanding this relationship is crucial to gaining control over heart disease risk.

(Note that I did not say "LDL cholesterol"--This is what confuses people, the notion that cholesterol is used as a surrogate marker to quantify various lipoproteins, including low-density lipoproteins, LDL. I'm NOT interested in the cholesterol; I'm interested in the behavior of the low-density lipoprotein particle. There's a difference.)

Carbohydrates:

1) Increase triglycerides and very low-density lipoprotein particles (VLDL)
2) Triglyceride-rich VLDL interact with LDL particles, making them smaller. (A process mediated by several enzymes, such as cholesteryl-ester transfer protein.)
3) Smaller LDL particles are more oxidizable--Oxidized LDL particles are the sort that are taken up by inflammatory white blood cells residing in the artery wall and atherosclerotic plaque.
4) Smaller LDL particles are more glycatable--Glycation of LDL is an important phenomenon that makes the LDL particle more atherogenic (plaque-causing). Glycated LDLs are not recognized by the LDL receptor, causing them to persist in the bloodstream longer than non-glcyated LDL. Glycated LDL is therefore taken up by inflammatory white blood cells in plaque.

Of course, carbohydrates also make you fat, further fueling the fire of this sequence.

The key is to break this chain: Cut out the carbohydrates. Cut carbohydrates and VLDL and triglycerides drop (dramatically), VLDL are unavailable to transform large LDL into small LDL, small LDL is no longer available to become oxidized and glycated, blood sugar is reduced to allow less glycation. Voila: Less atherosclerotic plaque growth.

Yet the USDA, American Heart Association, and the Surgeon General's office all advise you to eat more carbohydrates. The American Diabetes Association tells you to eat 70 grams or so carbohydrates per meal. (Yes: Diabetes, the condition that is MOST susceptible to these carbohydrate effects.) Follow their advice and you gain weight; triglycerides and VLDL go up; calculated (Friedewald) LDL may or may not go up, but true measured LDL (NMR LDL particle number or apoprotein B) goes way up; small LDL is triggered . . . You know the rest.

The dance between carbohydrates and LDL particles requires the participation of both. Allow one partner to drop out of the dance and LDL particles will sit this dance out.

Strange but true: Part II

4. April 2010 William Davis (0)

Here's the second part of the Heart Scan Blog post I wrote a couple of years back describing the wacky origins of this thing that has so changed the face of heart care in the U.S., the cardiac catheterization.

Heart catheterization: Strange, but true

3. April 2010 William Davis (1)

It's a couple of years old, but this post from March, 2008, remains relevant.

It details the curious origins of heart catheterization, the procedure that has saved some lives, but also been responsible for the proliferation of unnecessary heart procedures.

The modern era of heart disease care was born from an accident, quirky personalities, and even a little daring.

The notion of heart catheterization to visualize the human heart began rather ignominiously in 1929 at the Auguste-Viktoria Hospital in Eberswalde, Germany, a technological backwater of the day. Inspired by descriptions of a French physician who inserted a tube into the jugular vein of a horse and felt transmitted heart impulses outside the body, Dr. Werner Forssmann, an eager 25-year old physician-in-training, was intent on proving that access to the human heart could be safely gained through a surface blood vessel. No one knew if passing a catheter into the human heart would be safe, or whether it would become tangled in the heart’s chambers and cause it to stop beating. On voicing his intentions, Forssmann was ordered by superiors not to proceed. But he was determined to settle the question, especially since his ambitions captured the interest of nurse Gerda Ditzen, who willingly even offered to become the first human subject of his little experiment.

Secretly gathering the necessary supplies, he made his first attempt in private. After applying a local anesthetic, he used a scalpel to make an incision in his left elbow. He then inserted a hollow tube, a catheter intended for the bladder, into the vein exposed under the skin. After passing the catheter 14 inches into his arm, however, he experienced cold feet and pulled it out.

One week later, Forssman regained his resolve and repeated the process. Nurse Ditzen begged to be the subject, but Forssmann, in order to allow himself to be the first subject, tricked her into being strapped down and proceeded to work on himself while she helplessly watched. After stanching the oozing blood from the wound, he threaded the catheter slowly and painfully into the cephalic vein, up through the bicep, past the shoulder and subclavian vein, then down towards the heart. He knew that simply nudging the rubber catheter forward would be sufficient to direct it to the heart, since all veins of the body lead there. With the catheter buried 25 inches into his body, Forssmann untied the fuming Ditzen. Both then ran to the hospital’s basement x-ray department and injected x-ray dye into the catheter, yielding an image of the right side of his heart, the first made in a living human.

Thus, the very first catheterization of the heart was performed.

An x-ray image was made to document the accomplishment. Upon hearing of the experiment, Forssmann was promptly fired by superiors for his brazen act of self-experimentation. Deflated, Forssmann abandoned his experimentation and went on to practice urology. He became a member of the Nazi party in World War II Germany and served in the German army. Though condemned as crazy by some, physicians in Europe and the U.S., after hearing of his experience, furthered the effort and continued to explore the potential of the technique. Forssmann himself was never invited to speak of his experiences outside of Germany, as he had been labeled a Nazi.

Many years after his furtive experiments, the once intrepid Dr. Forssmann was living a quiet life practicing small town medicine. He received an unexpected phone call informing him that he was one of three physicians chosen to receive the 1956 Nobel Prize for Medicine for his pioneering work performing the world’s first heart catheterization, along with Drs. André Cournand and Dickinson W. Richards, both of whom had furthered Forssmann’s early work. Forssmann remarked to a reporter that he felt like a village pastor who was made a cardinal.

Strange, but true.

Rerun: To let low-carb right, you must check POSTPRANDIAL blood sugars

2. April 2010 William Davis (12)

Checking postprandial (after-eating) blood sugars yields extraordinary advantage in creating better diets for many people.

This idea has proven so powerful that I am running a previous Heart Scan Blog post on this practice to bring any newcomers up-to-date on this powerful way to improve diet, lose weight, reduce small LDL, reduce triglycerides, and reduce blood pressure.

To get low-carb right, you need to check blood sugars

Reducing your carbohydrate exposure, particularly to wheat, cornstarch, and sucrose (table sugar), helps with weight loss; reduction of triglycerides, small LDL, and c-reactive protein; increases HDL; reduces blood pressure. There should be no remaining doubt on these effects.

However, I am going to propose that you cannot truly get your low-carb diet right without checking blood sugars. Let me explain.

Carbohydrates are the dominant driver of blood sugar (glucose) after eating. But it's clear that we also obtain some wonderfully healthy nutrients from carbohydrate sources: Think anthocyanins from blueberries and pomegranates, vitamin C from citrus, and soluble fiber from beans. There are many good things in carbohydrate foods.

How do we weigh the need to reduce carbohydrates with their benefits?

Blood sugar after eating ("postprandial") is the best index of carbohydrate metabolism we have (not fasting blood sugar). It also provides an indirect gauge of small LDL. Checking your blood sugar (glucose) has become an easy and relatively inexpensive tool that just about anybody can incorporate into health habits. More often than not, it can also provide you with some unexpected insights about your response to diet.

If you’re not a diabetic, why bother checking blood sugar? New studies have documented the increased likelihood of cardiovascular events with increased postprandial blood sugars well below the ranges regarded as diabetic. A blood sugar level of 140 mg/dl after a meal carries 30-60% increased (relative) risk for heart attack and other events. The increase in risk begins at even lower levels, perhaps 110 mg/dl or lower after-eating.

We use a one-hour after eating blood sugar to gauge the effects of a meal. If, for instance, your dinner of baked chicken, asparagus brushed with olive oil, sauteed mushrooms, mashed potatoes, and a piece of Italian bread yields a one-hour blood sugar of 155 mg/dl, you know that something is wrong. (This is far more common than most people think.)

Doing this myself, I have been shocked at the times I've had an unexpectedly high blood sugar from seemingly "safe' foods, or when a store- or restaurant-bought meal had some concealed source of sugar or carbohydrate. (I recently had a restaurant meal of a turkey burger with cheese, mixed salad with balsamic vinegar dressing, along with a few bites of my wife's veggie omelet. Blood sugar one hour later: 127 mg/dl. I believe sugar added to the salad dressing was the culprit.)

You can now purchase your own blood glucose monitor at stores like Walmart and Walgreens for $10-20. You will also need to purchase the fingerstick lancets and test strips; the test strips are the most costly part of the picture, usually running $0.50 to $1.00 per test strip. But since people without diabetes check their blood sugar only occasionally, the cost of the test strips is, over time, modest. I've had several devices over the years, but my current favorite for ease-of-use is the LifeScan OneTouch UltraMini that cost me $18.99 at Walgreens.

Checking after-meal blood sugars is, in my view, a powerful means of managing diet when reducing carbohydrate exposure is your goal. It provides immediate feedback on the carbohydrate aspect of your diet, allowing you to adjust and tweak carbohydrate intake to your individual metabolism.

LDL glycation

1. April 2010 William Davis (11)

The proteins of the body are subject to the process of glycation, modification of protein All posts by william-davis

Take a walking vacation

20. May 2006 William Davis (1)

If you're planning a vacation, why not consider a walking vacation?

The concept is really taking off. All you need is a pair of comfortable shoes and an interesting locale. More and more services are popping up to help you plan fun and interesting destinations and itineraries. One such catalog can be found at http://walking.about.com/od/tours/a/walkingvacation_3.htm

Lengthier walks may require some advance planning and toting some supplies. Don't forget the water!

From a health viewpoint, a walking vacation sure beats the heck out of a cruise that packs on 12 pounds of extra weight from the 24-hour a day buffet. If you're in the midst of a weight loss effort, several hours of walking through interesting locales and scenery can make it effortless.

There's loads of neat places to visit from a walker's perspective. One interesting website is www.waterfallwalks.com that lists trails that provide spectacular views of waterfalls.

Another variation on this theme is biking vacations. My wife and I are trying to set the time aside for a biking tour of wineries in the French countryside. That's our kind of multi-tasking!

"Expanded indications for implantable defibrillators"

19. May 2006 William Davis (0)

So reads the headline on a magazine I received recently (along with thousands of my colleagues) from a major hospital system.

It goes on to say: "In January 2005, indications for implantable cardioverter-defibrillators (ICDs) were substantially broadened [emphasis ours] to include most patients with a left ventricular ejection fraction (EF) of 35% or less. This change translates into a 2- to 3-fold increase in the number of Medicare beneficiariries eligible for ICDs."

Ka-ching!!! Hear the money piling up in the bank?

The device manufacturers are constantly churning data and lobbying for reimbursement to expand the use of their devices to more and more people. Defibrillators in particularly are generally a $25,000 to $50,000 opportunity for the device manufacturer alone, not counting the costs incurred at the hospital for implantation.

Beware. As reimbursement for stents and other procedures diminishes, expect a sudden "demand" for more and more people to get implantable defibrillators. Better yet, stay away from the whole issue by preventing your heart attack.

Get a heart scan--but then don't delay taking action!

19. May 2006 William Davis (2)

I just came from one of the local hospitals after having performed a heart catheterization on a patient I met earlier this week.

Jack had gotten a heart scan a year ago with a score of 246, placing him in the 76th percentile. The "event" rate with this percentile rank is around 3% per year--not very high but enough to pose risk over a long period.

Jack chose to ignore his score. After all, the pressures of work at the University, maintaining his home and yard, etc. consumed all his energies. He came to my office--now one year after his scan--and told me about the chest pressure he was getting. Initially, his chest pains occurred with extended walking. In the past week, however, Jack was experiencing chest pressure with just walking 30 feet.

This pattern of increasing symptoms is called "accelerated angina", meaning that Jack was rapidly heading towards a heart attack. So I advised a heart catheterization in near future.

Jack's catheterization showed extensive plaque including a 50% blockage in the mainstem artery and 90% in the artery to the front of the heart (left anterior descending artery). Jack is going to have a bypass operation tomorrow.

What if Jack hadn't ignored his heart scan from a year ago? Well, I'd be very confident in saying that he would not be undergoing bypass surgery tomorrow.

The lesson: Don't dilly-dally on taking action to keep your plaque from growing. While it's not an emergency, it can easily become one if you choose to ignore your scan.

Feel that nudge in your back?

17. May 2006 William Davis (0)

You feel that nudge in your back? That's your local hospitals competing for your bypass surgery business.

Just this morning while watching a morning news show, I saw three advertisements for hospital bypass surgery programs. One ad featured a man in his 50s telling his story:"The cardiologist determined immediately that I needed a triple bypass operation. My family and I are very grateful to _____ hospital!"

In what other field is failure celebrated so prominently? When I see these ads, I hear "My doctors failed to provide early detection and then prevent what became a life-threatening condition, even though heart disease is a chronic process that requires decades to develop." What if our man said instead,"I had a heart scan and my score was high. So I was shown why I had so much plaque. They then showed me how to control and even reduce the amount of plaque I had. I'm living safely and symptom-free without need for surgery or procedures."

Of course, the hospital is out $60,000-100,000 for the surgery. How else could they afford ad campaigns costing several million dollars a year? See these advertisements for what they are: Marketing generated by profit-seeking businesses competing for your dollars--lots of them.

Throw away total cholesterol!

17. May 2006 William Davis (1)

Richard's total cholesterol without treatment was 186 mg/dl. "That's great!" his doctor declared, referring to the conventional dictum that total cholesterols less than 200 carry low risk. Several fingersticks in a mall kiosk set up by a local hospital to check total cholesterols confirmed Richard's low number.

But after Richard's unexpected hospitalization and two stents for severe coronary blockages, he demanded better answers.

Tragically, the answer was there all along: Despite a "favorable" total cholesterol, his HDL ("good") cholesterol was a miserable 32 mg (ideal >60 mg).

Total cholesterol is actually the sum total of HDL cholesterol, LDL cholesterol, with a contribution from triglycerides. That's why a low total cholesterol can conceal a low HDL.

This situation is quite common. And low HDL is accompanied by a constellation of other undesirable causes of heart disease, most notably small LDL.

Don't accept total cholesterol as your sole measure of risk. It's nearly worthless. If you live in Bangladesh or a third world country, well perhaps that's the best you can get. But if you live in the U.S. or developed world, it's absurd to rely on total cholesterol.

Smart Start not so smart

15. May 2006 William Davis (2)

Kellogg's has crafted a campaign to support the American Heart Association featuring acress Sela Ward. Her attractive face, familiar to many TV and movie viewers, does add a comforting face to their efforts.

What's in this cereal made by the manufacturers of Pop-Tarts, Cheez-It, Rice Krispies, and Chips Deluxe cookies?

There are, indeed, some healthy ingredients: oat bran, potassium; you can even get a version made with soy protein. But there's sugar listed as the second ingredient. High-fructose corn syrup is also listed prominently. (Remember this issue? High-fructose corn syrup causes overwhelming sugar cravings, causes your triglycerides to skyrocket, and is probably among the principal food ingredients that make you obese.)

Upon detailed questioning of my patients struggling to lose weight, this and products like it are often among the "healthy" foods they've gravitated towards. We spend a great deal of time dissuading them of this idea.

A one-cup serving of Smart Start is low in fat (1 gram) but contains 43 grams of carbohydates, of which there are 14 grams of sugar. There are a meager 3 grams of fiber. To me, this sounds like a cupcake.

The Kellogg's people are exceptionally clever marketers. Partner with the American Heart Association and movie stars? Brilliant!

You should trust food manufacturer advertising about as much as you trust drug manufacturer advertising, which is to say not at all.

Kellogg's sold $10 billion dollars of food products last year. They are the world's leading producer of breakfast cereals. They are a leading producer of convenience foods: cookies, crackers, cereal bars, and frozen waffles under the brands Keebler, Pop-Tarts, Eggo, Cheez-It, Nutri-Grain, Rice Krispies, Famous Amos, and Kashi.

Can they cash in on healthy trends? They'll certainly try.

Does anybody have a normal vitamin D level?

15. May 2006 William Davis (0)

We now routinely check everyone's vitamin D blood level at the start of the program. (The measure to obtain is 25-OH-Vitamin D3. This is not to be confused with 1,25-OH2-vitamin D3, which is a kidney function measure.)

Of the 10 people with levels drawn today, none were even close to normal levels (which we define as 50 ng/ml)--not a single one.

The majority were in the range of severe deficiency (<20 ng/ml). Only two had levels in the 30s. None had higher. (Remember: I'm talking about people in Wisconsin, a terribly sunlight-deprived area much of the year. This might not apply quite as vigorously to Florida residents or others in sun-exposed regions.)

Curiously, I've also seen several people this week who had extraordinary quantities of coronary plaque on their heart scans (scores >1000), all of whom had extremely low vitamin D levels. One of these people had fairly unimpressive lipoproteins, with very minimal abnormalities identified. (This is quite unusual, by the way.) It makes you wonder if a profound deficiency of vitamin D is sufficient to act on its own as an instigator of coronary plaque.

The more we examine the issue of vitamin D deficiency, the more fascinating it gets. I suspect we've just scratched the surface and there's a lot more to learn about this tremendously interesting nutrient. Nonetheless, with what we're seeing in our experience, I'm urging everyone to get a blood vitamin D level.

Don't believe your LDL cholesterol!

14. May 2006 William Davis (0)

Harry's case is typical. For years, his doctor told him his LDL cholesterol of 123 mg was okay. But a heart scan score of 490 (90th percentile at age 52) made him question just where his coronary plaque came from.

Lipoprotein analysis told a very different story: His LDL particle number was 2400 nmol, meaning his trueLDL was more like 240 mg, nearly double the value of LDL obtained through his doctor. Harry had other sources of risk, too, but the LDL particle number was a clear stand-out.

Why does this happen? How can LDL cholesterol be so terribly inaccurate?

LDL cholesterols obtained in virtually all labs are not measured, they're calculated. The calculation was developed in the 1960s by Dr. Friedewald at the National Institutes of Health and therefore goes by his name (the Friedewald calculation). Dr. Friedewald derived this simple calculation to permit doctors across the U.S. to obtain LDL cholesterols, which were technically difficult to measure in those days by using measured HDL, total cholesterol and triglycerides.

Doctors were told that the only time that the Friedewald calculated LDL was inaccurate was when triglycerides exceeded 400 mg. So most family practitioners and internists still believe that calculated LDL's are, for the most part, quite accurate.

Nothing could be further from the truth. When LDL's are actually meaured, you find that LDL is rarely accurate. In fact, in our experience, inaccuracy of 30-50% is the rule, sometimes 100%. The one telltale hint that calculated LDL is wrong is when HDL is <50 mg--that's nearly everybody.

So what's your LDL? You won't really know unless it's measured. Our preferred method is NMR (LipoScience) LDL particle number, probably the most accurate of all. Second best: apoprotein B,