The Good, the Bad, and the Worse

Like so many things, cholesterol isn’t bad for you unless there’s too much of it, at which point it begins to cause trouble. The story isn’t quite that simple, however. As you probably already know, there are different kinds of cholesterol—some bad, some good. And how much you have of each type makes a tremendous difference in your likelihood of developing CHD.

It’s actually not cholesterol per se that’s good or bad for you, but the’ “vehicle” through which it travels ‘ your  bloodstream. Because cholesterol is waxy, it can’t mix with blood, which is watery. Like oil in a salad dressing, it Americans eat, remains separate.  

Your body manufactures three or four times more cholesterol than most Americans eat.

To enter the cells and tissues where it’s needed, then, it hooks up with proteins, creating special transporters called lipoproteins. Think of these as submarine-like bubbles that carry cholesterol around the body. Some of these “submarines” are friends, but most are foes.

LDLs: Low-Density Lipoproteins

Low-density lipoproteins, or LDLs, are the primary foes—the archenemies, in fact.
LDLs carry most of the cholesterol (75 to 80 percent) in the blood, depositing it into the cells, including the arteries, There these particles contribute to the formation of plaque, which narrows the arteries. That reduces the amount of blood that can get through, diminishing the amount of oxygen that reaches the heart.

Some LDL types are more dangerous than others. Smaller, denser LDL particles are more damaging to blood vessels because it’s easier for them to cross the lining of the vessel and burrow into the vessel wall.

Most people won’t know what type of LDL they have because the tests to determine it are too expensive and complicated for the typical doctor’s office. If you already have CHD, or have a strong family history of CHD, and your doctor has sent you to a cardiac specialist, that doctor may run more detailed tests to better understand your risk. But it doesn’t matter much, as the focus remains the same regardless: Lower the
amount of LDL in your body.

So what’s the ideal LDL level? As you’ll read in Chapter 3, that depends on your personal history and other risk factors for CHD. But if you’re a man 45 or older or a wornan 55 or older and don’t have CHD, diabetes, hypertension, or a family history of premature CHD, and dont smoke, here’s what you should aim for (levels are measured in milligrams per deciliter, or mg/d-la deciliter is about 3 ounces)

LDL levelCategory
Less than 100 mg/dlOptimal
100-129 mg/dlNear optimal
130-159 mg/dlBorderline high
160-189 mg/dlHigh
190 mg/dl and aboveVery high

Everything from your weight to whether or not you smoke to your family health
history—even the amount of stress you’re under—affects your LDL level. Of course,
your diet makes a difference, too, particularly the types of fats you eat. You’ll read
much more about these fats in Chapter 4.

HDLs: High-Density Lipoproteins

High-density lipoproteins, or HDLs, are the good guys—the “garbage trucks” of the bloodstream, as described by C. Noel Bairey Merz, M.D., director of the Preventive and Rehabilitative Cardiac Center at Cedars-Sinai Medical Center in Los Angeles. HDLs typically transport about 20 to 25 percent of the cholesterol in your blood, carrying it away from tissues to your liver, which disposes of it. The more HDL in your bloodstream, the more artery-clogging cholesterol is being removed.

Research finds that for every 1 percent increase in your HDL level, your risk of a heart attack drops 3 to 4 percent. By comparison, a | percent drop in your LDL level  reduces your risk of a heart attack just 2 percent. HDL is so beneficial that a high level may offer enough protection to cancel out a heart disease risk factor like having chabetes or being overweight.

Having low HDL, on the other hand, often signifies other problems. For instance, mary people with low HDL also have high levels of other dangerous blood fats, such as triglycerides and remnant lipoproteins (more on this later). That makes sense, since low HDL means fewer “garbage trucks” disposing of the “trashy” cholesterol. Low HDL can also be a sign of insulin resistance and metabolic syndrome, or Syndrome X. risks you’ll learn about in Chapter 2.

HDL levelCategory
Less than 40 mg/dlLow (risky)
10-59 mg/dlAverage (neutral)
60 mg/dl and aboveHigh (protective)

Smoking, being overweight, being sedentary, and consuming a high carbohydrate diet (more than 60 percent of your calories) contribute to low HDL. So does a family history of low HDL. In fact, about half af HDL imbalances are due to genetics, Women are lucky in that they generally have a higher HDL level than men. But some doctors think women need these higher levels to remain healthy. and they suggest an HDL level even higher than 60 (the usual target) is most desirable for womens.

Total Cholesterol

The basic cholesterol test measures LDL and HDL, along with two other components
you’ll read about shortly: very low-density lipoproteins (VLDL) and triglycerides.
Together these make up your total cholesterol count.

So what should your total cholesterol be? The goal has changed twice since it was first devised in 1988, It’s not an arbitrary number, however. It’s set by the National Institutes of Health’s Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults, a true mouthful that you don’t have to remember. The panel periodically releases a report—the third one came out in 2001—called the Adult Treatment Panel Report.

Based on the latest research, experts believe a safe total cholesterol level is about 150 mg/dl. (By contrast, the average total cholesterol level in the United States is between 200 and 210.) As you’ll find out later in the book, this total cholesterol target isn’t a one-size-fits-all measure. The goal you set depends not only on where your cholesterol levels are today, but also on other risk factors, including your weight, physical activity, diet, and family health history.

The Ratio’s the Key

What’s even more important than your total cholesterol, LDL, or HDL alone is the proportion of good to bad cholesterol in your blood. As long as you strike the right balance, you’re probably in the clear.

Here’s one reason that HDL and LDL numbers on their own don’t tell the whole story: People who eat diets low in animal fat tend to have low HDL, even though their heart disease risk is small. “If you simply looked at populations in the world,” notes John Larosa, M.D., president and professor of medicine at the University of New York Health Science Center at Brooklyn, “those with the lowest HDLs—that is, populations with the lowest amount of animal fat in their diet—have the lowest risk of coronary disease. So HDL is a good predictor of risk in populations only as long as LDL levels are fairly high.”

There are several ways doctors measure the proportion of different types of cholesterol in the blood, One is by calculating your ratio of total cholesterol to HDL, You can figure out this number by dividing your total cholesterol by your HDL. If your total cholesterol is 240 and your HDL is 60, your ratio is 4:1. An acceptable ratio is less than 5:1, although an even better ratio is less than 4.5:1 for men and 4:1 for premenopausal women. A truly ideal ratio is 3.5:1

Non-HDL Cholesterol

Another up-and-coming indicator of your overall risk of heart disease is your non HDL cholesterol count. You see, not all “bad” cholesterol is equally bad. While LDL has long been the focus of cholesterol reduction efforts, researchers have recently identified several other lipoproteins, including VLDL and IDL (intermediate-density lipoproteins) that also affect your cardiovascular health. To take these into account, they’ve come up with a new measurement and focus of treatment: non-HDL cholesterol. Your non-HDL cholesterol count is simply your total cholesterol minus HDL, or put another way, the sum of your LDL, VLDL, and IDL.

In late 2002 researchers published an article in Circulation, the journal of the
American Heart Association, confirming that if you have heart disease, your non-HDL level can help predict your risk of a heart attack or angina (chest pain) and determine treatments. “LDL cholesterol, even though it is a ‘bad’ cholesterol, tells only part of the story,” said lead author Vera Bittner, M.D., MSPH, professor of medicine in the division of cardiovascular diseases at the University of Alabama at Birmingham. “We found that while LDL cholesterol is important, the non-HDL cholesterol is the more important predictor—at least in this group of people with heart disease.”

Many people won’t know their levels of VLDL and IDL, and that’s okay. Current recommendations call for obtaining at least a total cholesterol and HDL level to
determine CHD risk. If these levels don’t raise any red flags, there’s no reason to investigate further (unless you have CHD or a strong family history of heart disease), But if the levels are elevated, you’ll probably need more detailed tests, possibly including VLDL and IDL counts.

If your LDL goal is:Your non-HDL goal should be:
Less than 160 mg/dlLess than 190 mg/dl
Less than 130 mg/dlLess than 160 mg/dl
Less than 100 mg/dlLess than 130 mg/dl

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