Cholesterol

by Dr. Neal Pinckney
heart.kumu.org

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 RatioWomen's Ratio
Very Low
(half of average risk)
under 3.0Under 3.3
Low4.03.8
Average5.04.5
Moderate
(2 times average risk)
9.57.0
High
(3 times average risk)
23.0 or more11.0 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

For a more complete explanation of the meaning of cholesterol numbers, go to Understanding Laboratory Test Results.