Cholesterol, HDL. LDL, Trigylcerides and Heart Health

Present in the tissue of all animals, cholesterol is needed by the body as a structural element in all cell membranes, a building block for some hormones and many other important functions. The problem is having too much of this white, fat-like waxy material. The liver and other organs of most people produce between 500 and 1000 milligrams of cholesterol a day, which is usually more than the body needs. The extra amount is filtered out. Adding cholesterol in our diet is seldom necessary.
All animal products contain cholesterol. When meat, fish, fowl, eggs or dairy products are eaten, additional cholesterol is added to that which we make ourselves, and often this is more than the body's cholesterol filtering system can eliminate.

Scientists are not in complete agreement about how cholesterol circulates through our body, but they believe the liver makes bubbles of proteins combined with triglycerides (fats) and cholesterol, called lipoproteins. A Very Low Density Lipoprotein (VLDL), the largest of these, deposits triglycerides in fat cells and muscles to be stored until they are needed. When the VLDL releases triglycerides, the bubble becomes smaller and then carries the cholesterol to the cells for metabolism. This smaller cell changes to a Low Density Lipoprotein (LDL). LDL is often called bad cholesterol, since it adds to the total cholesterol already in the bloodstream. When there is more cholesterol than is needed by the cells, the liver's LDL receptors try to filter it out to be excreted as waste. Saturated fats can prevent these LDL receptors from doing their job. There is often far more cholesterol than can be filtered and eliminated, and it circulates in the bloodstream, eventually accumulating on the walls of the arteries. These accumulations build up small nodules, called plaque, that obstruct the flow of blood. More information about this build- up can be found in the section on atherosclerosis.

The liver also makes a High Density Lipoprotein (HDL), which holds less cholesterol than the LDL. When this circulates it can pick up cholesterol and bring it back to the liver, where some of it is filtered and eliminated. HDL is often called good cholesterol, since it can be beneficial in lowering the total cholesterol in the blood. Exercise can be helpful in raising HDL "good" cholesterol.

The cholesterol you get from what you eat, made outside your body, is never good" cholesterol. When you consume foods that have cholesterol, which can only come from animal products, you are adding to the chance of forming plaque and clogging your arteries. Saturated fats can interfere with the process that filters and eliminates cholesterol, increase the cholesterol level in your body. Fats are explained in more detail here.

Studies of people in two countries illustrate how what we eat can affect cholesterol. In China a wide, scientifically selected sample from every single county, a total of 6,500 people, has been under examination since 1983. Their food intake and life habits have been carefully logged, and they have been subjected to many medical diagnostic tests. The typical Chinese eat very little animal protein or saturated fats. Their usual cholesterol levels (average 88-165) are lower than Americans (average 155-274), and coronary heart disease is rare among Chinese. Death from colon cancer is also extremely low. The Japanese, who traditionallconsume very low levels of saturated fats, have the lowest levels of cholesterol and heart disease of all industrialized countries.

Compare this to Finland, which has the highest consumption of saturated fats, the highest cholesterol levels and the highest rate of heart disease. The U.S. diet is only slightly less rich than the Finns, and we have the second highest rate of heart disease.

Lowering cholesterol is best accomplished by changing the foods you eat. Eliminating saturated fats and reducing the cholesterol in your diet are both important to good health. Dr. Ornish, in his heart disease reversal program, recommends eating foods with no more than 5 milligrams of cholesterol a day, a small glass of non-fat milk or a 4 ounce serving of fat-free yogurt. Even that small amount may make it difficult for you to bring your cholesterol level below 150 mg/dl, where it needs to be to begin to reverse the damage already caused in your arteries. It was once thought that anything under 200 mg/dl was a safe cholesterol level, and many physicians and health foundations are still satisfied with that number, but more recent research shows the reversal process improves and the risk of heart attack lowers most when the cholesterol level is below 150. Above 200, for every point cholesterol is reduced, the risk of heart attack is lowered by 2%.

For people in good health and who have no family history of heart disease or other risk factors, there may be no immediate danger in consuming foods with small amounts of cholesterol. But those with an elevated risk of heart disease should avoid dietary cholesterol. Since saturated fats prevent the body from removing excess cholesterol, these also should be reduced or eliminated. A national consumer education organization warned that a medium size bag of buttered popcorn sold at movie theaters may have more saturated fat than a breakfast of bacon and eggs, a large hamburger with french fries for lunch and a steak dinner with all the trimmings. Sound impossible? Movie theater popcorn is typically popped in coconut or palm oil, extremely high in saturated fat.

Other things can be done to lower cholesterol beside watching what you eat. An important benefit will likely happen automatically to most people when they follow a proper diet and take off a few pounds. Being overweight leads to higher LDL and total cholesterol. Most people find that for every two pounds of excess fat that is lost, one point (mg./dl.) of total cholesterol is also lost. Just losing 20 pounds will likely reduce your cholesterol by 10 points. In Healing Heart support groups overweight most people who followed the diet faithfully and who started a moderate exercise program lost an average of over 2 pounds a week for the first 10 weeks - and they kept it off. When your body reaches the weight that is best for you, you should still be able to eat all you want of the proper foods, without counting calories, and remain at that weight.

Exercise is important in reducing cholesterol. A daily program of aerobic exercise will help you to lower and keep down your cholesterol level. As you exercise aerobically, your blood pumps through the arteries at a higher rate, and the High Density Lipoproteins (H DL) can carry more cholesterol away. Aerobic exercise at least 40 minutes a day, at least five days a week, is needed to get maximum benefits in reversing heart disease and lowering risk.

Cholesterol-lowering medications are commonly recommended.. If prescribed by your physician, continue to take them as directed. As you follow all the elements recommended here and your cholesterol goes down, your doctor may wish to gradually lower the dosage of some medications. Many Healing Heart support group participants were able to stop taking their medications completely after a short while. Don't alter your medications on your own; always discuss any change in medications you may want to make with your doctor. If your physician doesn't want you to reduce the medication, ask why. If the answer doesn't satisfy you, it is better to look for a different doctor than to keep the same one and ignore the advice given. Some over- the-counter preparations claim to reduce cholesterol, and they may possibly help, though there are often unwanted side-effects. Psyllium based supplements, for example, can cause some people to have diarrhea, stomach cramps and a bloated feeling. Using psyllium instead of eating fiber- rich foods can cause some people to depend on a daily dose to keep their bowels moving normally. Psyllium is mostly dietary fiber, but a low-fat vegetarian diet will give you all the fiber you need for reducing cholesterol and to maintain normal bowel function.

Testing blood for cholesterol is simple and inexpensive. The most accurate measure comes from blood drawn by a professional laboratory and analyzed with constantly recalibrated equipment operated by skilled technicians. The finger pin-prick tests are only as accurate as the equipment and skill of the person doing it. Since these portable machines are moved from place to place, they require more frequent calibration and adjustment, which is not always done. When you are having your cholesterol measured, don't exercise for at least two hours before the test, as exercise can temporarily elevate cholesterol levels. Illness, pregnancy, some medications and recent surgery can influence blood cholesterol levels. If your test measures LDL or triglycerides, you should not eat or drink anything (except water) for at least 14 hours before the blood is drawn. Always call ahead to see if LDL or triglycerides are to be tested.

When results come back make sure you get the exact number of all the measurements. You can use the chart at the end of the appendix to record them. Don't be satisfied with being told your cholesterol is normal or you're OK . Reversing heart disease means maintaining levels of cholesterol much lower than what is normal for others.

One of the figures you may be given is a Risk Factor Ratio. This is usually the total cholesterol divided by the HDL. This ratio, according to your age and sex, can give an indication of the risk of dying from heart disease.

Risk factor (Total / HDL)

Men's Ratio

Women's Ratio

Very Low (half of average risk) under 3.0 Under 3.3

Low 4.0 3.8

Average 5.0 4.5

Moderate (2 times average risk) 9.5 7.0

High (3 times average risk) 23.0 or more 11.0 or more

For years we've been hearing the advice to eat chicken or fish instead of beef, pork or lamb. What is hard for many people to accept is that the leaner the meat, the more cholesterol it contains. Each ounce of lean beef will have between 20 and 25 mg. of cholesterol, depending on the cut, but an ounce of lean chicken with skin removed can have more than beef, often has 25 mg. An ounce of dark turkey meat contains 32 mg. of cholesterol, and fish contains from 10 mg. to over 100 mg. of cholesterol per ounce (often 5 times that of steak). All animal products contain cholesterol but no plant foods have measurable amounts of cholesterol.

Physicians at the Weimar Institute have determined that the average American male eats foods containing about 500 milligrams of cholesterol a day, about the same amount as his body makes internally. The typical American female eats about 350 milligrams of cholesterol. Not one milligram of that is needed by the body, which makes all it needs.

Vegans, strict vegetarians who eat no dairy or egg products, consume no cholesterol in their diet. Numerous studies show that vegetarians live longer and have a fewer heart attacks and less coronary artery disease, diabetes and many types of cancer than the general population, the meat eaters. Many studies estimate that 70% of these diseases could have been prevented with changes in eating habits.

Much of what follows will explain how to reduce cholesterol and establish a lifestyle for optimum health.

Cholesterol is measured using different numbers in the U.S and in most of the rest of the world. In the U.S is is reported in deciliters per milligram (dl/mg), but elsewhere it is reported in millimoles per liter (mm/l). Click here for a conversion chart


Understanding the Meaning of Laboratory Tests

Participants in Healing Heart support groups are requested to have some laboratory tests done as they begin the program and then repeat these tests at the end of the ten week program. They can decide on the basis of changes in test results and the way they feel whether the lifestyle changes were worth the effort. Almost all have chosen to keep the changes, rather than return to their former lifestyle and problems. You are encouraged to do the same, getting your lipids, blood pressure, weight and body fat measured at the start and again at the end of ten weeks. Seeing the numbers change for the better is proof that the program is working for you. But what do those numbers mean? The following is a limited, brief explanation to help give you basic understanding of the the meaning and normal values of these tests. For more information, ask your physician for an interpretation of your test results.  

The cholesterol level in your blood is a highly useful indicator in your health profile. It is measured in the U.S. in milligrams per deciliter (mg/dl) (see box below). The typical level of total serum cholesterol (the amount most commonly found in Americans) is somewhere between 130 and 350 mg/dl., with the average around 215. To reduce plaque and heart attack risk, you should keep your cholesterol under 150. Cholesterol levels provide information about many risks. If your cholesterol level is near the 215 average mark, your lifetime risk of heart disease and stroke is greater than 50%, of gallbladder disease 40% (90% of gallstones are made out of cholesterol), of breast cancer in women 10% and of colon cancer 5%. Even small changes can have huge effects. Lowering the cholesterol level from 260 to 200 decreases the risk of dying from heart disease by 500%.

If your numbers are much different - somewhere between one and ten...it means that your lipids are measured in millimoles per liter (mm/l) as it is in most places outside of the US. You can multiply mm/l by 38.61 to get the equivalent in mg/dl (or multiply mg/dl by 0.0259 to get mm/l), or click here for cholesterol conversion.

In addition to total serum (blood) cholesterol, there are three lipoproteins which also give useful information. HDL (High Density Lipoprotein) is often called good cholesterol. The typical range in Americans is between 29 and 77. Any measure above 55 mg/dl is considered acceptable, but levels closer to 100 are related to a lower chance of coronary artery disease. In the process of lowering total cholesterol, HDL may also come down for a while. A Heart Risk Ratio is calculated by dividing total cholesterol by HDL. As total cholesterol is lowered, HDL will also often decline, sometimes causing the ratio to rise. This is not always a cause for serious concern, as the ratio has less significance as the total cholesterol level gets closer to 150. See the section on Risk Factors for an interpretation of the ratio. 

LDL cholesterol, which is often called bad cholesterol, is useful in assessing heart disease risk, but many physicians feel it is not nearly as important as the total cholesterol and HDL counts. The typical level in the U.S. is between 75 and 185. It is considered beneficial to keep LDL levels under 130, as higher levels are associated with greater risk.

Some labs also calculate VLDL, very low density lipoproteins. The typical range is from zero to 40 mg/dl. The link between VLDL and heart disease risk is less well established.

There is some controversy about tests to detect the level of C-reactive protein (CRT) and its value in predicting heart disease. On November 14, 2002, 2001 the New England Journal of Medicine published the results of one of the most definitive studies on this subject. To read a summary of that study, posted on the Healing Heart Discussion Group, click here.

Body Fat Percent is a way to determine the proportion of fat to other tissue. When fats are reduced and exercise increased, sometimes weight doesn't drop as expected. The fatty tissue may be replaced with newly formed muscle cells, which weigh more than fat. It is helpful to know the percent of fat in the body is being reduced, even if weight sometimes doesn't change as much as expected. To see general guide to body fat percentage, click here.

Triglycerides are the amounts of fats in your bloodstream. Since triglycerides usually go up after eating, a test for triglycerides should be taken only following 14 hours of fasting, eating no foods and drinking nothing but water. The typical triglyceride level is between 35 and 219 mg/dl, and levels below 100 are considered helpful in reducing heart disease risks. Triglyceride levels are somewhat different for men and women, and also change with age, rising to nearly double the value of age 6 by age 60, and then they slowly decline. Triglyceride levels commonly go up for three to six months when on a low fat, vegetarian diet. They usually go below the starting level for much improvement after that. Fats in the blood rise to the top like the fats in soups or gravies do after they cool. If people who eat the typcially high fat standard American diet could see their blood sample after 8 hours, with its layer of yellow-white fat floating above the red and sticking to the sides of the glass tube, it would be easier to motivate them to eat more sensibly.

Triglycerides, like cholesterol, is measured in mg/dl in the USA and in mm/l in most of the rest of the world, but the conversion factor for triglycerides is different from the one for cholesterol. For a triglycerides conversion chart, click here.

Blood Pressure is measured in two numbers. The higher number, called systolic, shows the highest amount of pressure on the walls of blood vessels during each beat of the heart. The lower number, diastolic, shows the amount of pressure on the arteries when the heart is resting between beats.

Various things can temporarily affect blood pressure, so it is usually best to take an average of many measurements rather than use only one. When some people go to a clinic their anxiety can cause blood pressure to be much higher than normal, a condition called white-coat hypertension . Recent use of coffee or tobacco can raise blood pressure. Many medications can raise or lower blood pressure.

Age, health problems and physical fitness are considerations in deciding if a person's blood pressure is normal. A general guide is given here, but you should check with your physician to decide if yours is safe or requires attention.
The following two tables show what is generally considered normal and high levels of blood pressure. Many different health conditions and medications may affect what is normal for each person.

Diastolic:

Level Hg/mm	Signifigance	Usual Recommendation
85 & below	normal	check @ 2 years
85 - 89	high-normal	check annually
90 - 104	mild hypertension	check 2 months later
105 - 114	moderate hypertension	medical intervention
115 & above	severe hypertension	therapy may be advised

When diastolic pressure is normal, a condition called isolated systolic hypertension may occur if systolic measures are abnormally high. This is more common in older persons.

Systolic:

Isolated Systolic Hypertension (when diastolic is under 90)

Level Hg/mm	Signifigance	Usual Recommendation
140 & below	normal	check @ 2 years
140 - 159	borderline	check 2 months later
160 - 199	hypertension	consult your physician
200 & above	acute hypertension	therapy may be advised

New research indicates that the top number in a blood pressure reading is more useful than the bottom number in determining heart disease risk. Doctors have typically looked at diastolic pressure (the bottom number) to assess whether people are at risk for heart disease, but a study published in the Archives of Internal Medicine in early 2002 adds to growing evidence that it's systolic blood pressure (the top number) that matters most.

In the study, researchers looked at 4,714 French men, whose average age was 52, for a period of 14 years. They found that during that period, men with systolic blood pressure of 160 or higher had more than twice the risk of death from heart disease compared to men with systolic blood pressure of less than 140. Systolic pressures between 140 and 160 were associated with a slightly increased risk. The diastolic pressure reading did not appear to have anyeffect on heart disease risk. Although earlier studies suggested that high systolic blood pressure was an important risk factor for elderly people, the new study shows that it is also important in middle-aged people. The researchers concluded that the optimal blood pressure reading is 120 over 80 or lower.

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Here's a rundown of some more common tests to determine if one has heart disease, what kind, and how serious, from simple to high-tech, which may be advised under different circumstances.

Electrocardiogram (ECG or EKG). This fast, painless testrecords the heart's electrical activity through small electrodes placed on your body. It is not usually part of the routine physical xam for healthy people, but may be done if you have symptomsor certain risk factors. It can detect a heart attack (past or present) r be used to diagnose specific problems, including irregular heart rhythms or enlarged heart chambers. A Holter Monitor allows for continuous ECG monitoring, via a small recorder and electrodes that you wear under your clothing for 24 hours (or longer). An event monitor, typically worn for several weeks, records heart activity only when you feel symptoms and push a button.

Exercise stress test. This is an ECG taken while you use a treadmill or stationary bike. It shows how much stress your heart can tolerate before problems develop, such as abnormal blood pressure or irregular heart rhythm, and can determine what a safe level of exercise is for you. Because you are exerting yourself, the effects of coronary blockage are more likely to show up here than in a regular ECG. Stress tests carry a slight risk and must be closely monitored by a physician or technician. Results may be less accurate in women.

Echocardiogram. A device (transducer) beams ultrasound waves at your heart, and the returning echoes are used to create a picture of the heart and its moving valves. If a "color Doppler" is used, blood flow through the heart can be evaluated. There are several kinds of echocardiograms, including a stress echocardiogram, done immediately after a treadmill workout, which can reveal abnormal heart contractions.

Myocardial perfusion. This nuclear imaging test evaluates blood flow to the heart. A small amount of radioactive material is injected in a vein, and then a special camera captures images as the substance passes through your heart and arteries. The test usually consists of two parts: one at rest and one after exercise (or a drug may be given that has a similar effect on the heart as exercise), and the images compared. In a heart free of blockages, there should be little difference at rest and after exercise.

Electron-Beam Computed Tomography (EBCT). This imaging procedure detects calciu deposits in coronary arteries, which may signal the presence of CAD. Studies have found that the higher the calcium, the higher the risk for heart attacks. But the use of EBCT is still being debated because it's unclear how much information it provides for predicting heart disease beyond an evaluation of standard risk factors. And it may expose many people to needless radiation, though the dose is low.

Computed tomography angiography (CTA). Also referred to as rnultidetector scanning, this rapidly developing imaging technology produces high-resolution, three-dimensional computerized pictures of the moving heart and large blood vessels, which reveal the extent and nature of plaque formation or calcium deposits. Contrast material may be injected in a vein to improve the quality of the images. Newer systems produce better images much faster-and with less radiation.

Coronary magnetic resonance imaging (MRI) or magnetic resonance angiography (MRA).This test uses magnetic fields and computers to produce images of the heart and arteries. It can detect valve problems, heart enlargement, and vessel disease, as well as damaged heart tissue and other abnormalities. Contrast material may be injected. An advantage is that it detects CAD without radiation and is not invasive. Though relatively new and expensive, it may turn out to be the preferred way to visualize the coronary arteries, and may one day be useful in diagnosing people who come to the emergency room with chest pain.

Coronary angiogram. This procedure involves inserting a catheter into a vein, which is then guided to the heart. Contrast material is injected to visualize the heart on X-rays and observe the heart, arteries, and valves at work. Angiography is the gold standard for diagnosing CAD,but because it isinvasive and involves some risks, it is done primarily in people who are candidates for coronary bypass surgery or angioplasty.

Testing you probably don't need: Some clinics offer EBCT, full-body CT scans, and ultrasound tests without a doctor's referral. There's no evidence these tests are worthwhile for people at low risk of heart disease-which is why most insurance won't cover them in people who have no symptoms or other significant risk factors. Moreover, tests that use X-rays, particularly fullbody CT scans, can expose you to high levels of radiation, especially when done repeatedly. All diagnostic tests produce false positive results (indicating disease when none is present), but more so in low-risk people. Such a result would lead to further unnecessary and costly procedures, as well as additional worry.

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