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.