Heart disease is the number one killer
of Americans, accounting for more
than 40 percent of all deaths in the
United States. While heart disease is a broad
term, it is used by doctors to describe atherosclerosis,
the main cause of heart attacks
and strokes. The National Cholesterol
Education Program (NCEP), a division of the
National Heart, Lung and Blood Institute
(NHLBI) of the National Institutes of Health
(NIH) has just released the latest guidelines
for identifying and managing risks for
coronary heart disease (CHD).
If you are like many health-conscious
individuals, you may be willing to take
several steps to prevent heart disease. You
make healthy food choices, you exercise and
you probably take several supplements for
your general health. However, you may be
confused about what other steps you can
take. You may wonder what role cholesterol
and blood lipids play in cardiovascular
health. You may wonder if you have any risk
factors for heart disease and what you can do
in terms of prevention. If you have already
been diagnosed with heart disease, you may
be wondering how you can supplement the
program your doctor has given you.
Atherosclerosis results from the buildup of
plaque along the walls of blood vessels. It begins
when the lining of the vessel is damaged. Fat
carrying proteins, called lipoproteins, attach
themselves to the damaged surface, causing
cholesterol to build up. The low density
lipoproteins (LDL) start to break down or oxidize,
releasing free radicals, damaging nearby
cells. The more LDL-cholesterol (LDL-C) in
your blood, the more it can build up on the
blood vessels. This whole process sets off the
immune system to try to repair the damaged
site, sending in specialized white blood cells,
called macrophages, which eat the LDL-C.
However when they become full of LDL-C,
they become useless foam cells which contribute
to the plaque formation. Chemical
signals called growth factors are released,
which cause fibrinogen (a sticky substance)
to adhere to the plaque, attracting platelets.
All these things together form a stiff plaque
on the artery wall and ultimately block the
artery. Your blood flow can be reduced by
90 percent before you feel any symptoms,
but then it is too late; CHD has occurred.
These plaques have the unfortunate
propensity to break loose, causing strokes,
heart attacks and other ischemic conditions
such as angina, poor kidney function,
reduced eyesight, poor circulation in the legs
(claudication). If in addition to poor lipids
levels, someone has other risk factors such as
hypertension (high blood pressure) or diabetes,
then these events are accelerated. A
heart attack (also called a myocardial infarction)
is when something blocks the flow of
blood to your heart—a clot, a spasm or an
accumulation of plaque. A stroke is brain
damage that occurs when blood flow to the
brain is interrupted, either by a clot or when
a blood vessel bursts. High blood pressure
plays a crucial role in the development of
heart disease and stroke. The higher the
pressure the greater the stress on arteries and
the more rapid the buildup of plaque. For
reasons that are not entirely known, diabetes
also increases plaque formation.
Blood Lipid Profile
When doctors order a lipid profile, they are
measuring the levels of all the cholesterol in
your blood, both good and bad. These
include: Total cholesterol (TC), Low density
lipoprotein (LDL-C—also known as the bad
cholesterol), Very low density lipoprotein
(VLDL-C—another bad player, very bad),
High density lipoprotein (HDL-C—the good
“healthy” cholesterol) and triglycerides
(TG—yet another bad player). They may
order additional tests such as glucose, to test
for diabetes and homocysteine levels, as elevations
of homocysteine are also implicated
in heart disease.
When people talk about their “cholesterol
level” they are usually referring to their total
cholesterol. The assumption that many
people make is simply “the lower, the better.”
In reality, a healthy lipid profile is more
complicated than simply low cholesterol.
Cholesterol is a natural substance found in
the body. The cells need a certain amount of
cholesterol to make flexible, permeable
membranes. The liver usually makes all the
cholesterol the body needs. The cholesterol
one ingests in the diet provides excess
amounts. Cholesterol travels from the
liver into the circulation by hitching a ride
on LDL. It is carried away from tissues and
back to the liver aboard HDL.
Perhaps even more important than the
total cholesterol level is the ratio of good
to bad cholesterol. High levels of HDL-C
are cardioprotective. One well-known way
to increase the level of HDL-C in the blood
is to increase one’s activity level.
Conversely, elevated levels of LDL-C are
associated with an increased risk of heart
disease, as are elevated triglycerides.
We need a certain amount of HDL-C
because as discovered in the 1970s, it actually
protects against the buildup of cholesterol
plaques. It acts as a scavenger preventing
plaques from adhering to vessel walls.
Without these scavengers, or when the ratio
of HDL-C to LDL-C is off, plaques can build
causing atherosclerosis (or hardening of the
arteries). An appropriate heart-healthy goal,
then, goes beyond “low cholesterol.” Instead,
we need to focus on a healthy lipid profile,
with appropriate ratios of HDL-C, LDL-C and
TG. Just as we should want to keep LDL-C
and TG down to appropriate levels, we should
also want to keep HDL-C up to an adequate
level. The new definitions of normal, borderline
and elevated cholesterol are more
stringent than previously, which means that
many more Americans will fall into “at risk”
categories, with physicians recommending
treatment. (For appropriate HDL and LDL
levels, see “New Recommendations” .)
New Recommendations
Because heart disease claims more lives than
any other condition in the United States (as
well as other industrialized countries), the
NHLBI is continually reviewing risk factors for
heart disease in order to find more effective
COMPARISON OF EARLIER AND NEW CHOLESTEROL GUIDELINES |
| Lipid |
Earlier NCEP* Guidelines |
New NCEP* Guidelines |
| LDL-cholesterol |
<130 mg/dl=optimal
130–159 mg/dl=borderline high
160 mg/dl=high
|
<100 mg/dl=optimal
100–129 mg/dl=above optimal
130–159 mg/dl=borderline high
160–189 mg/dl=high
>190 mg/dl=very high
|
| HDL-cholesterol |
>35 mg/dl=optimal |
>40 mg/dl=optimal |
| *National Cholesterol Education Program |
ways to prevent it. In this spirit, the NHLBI’S
National Cholesterol Education Program
(NCEP) has established new guidelines for a
healthy lipid profile. These guidelines establish
LDL-C as the target for therapy and
define as normal an LDL-C level of 100 mg/dl
or less (milligrams per deciliter of blood
serum). The new guidelines identify levels of
100–129 mg/dl as “above optimal.” Those of
130–159 mg/dl are still defined as “borderline
high,” and those at 160–189 mg/dl as “high.”
Those above 190 mg/dl are considered “very
high.” A healthy HDL-C level is defined as at
least 40 mg/dl. Previous guidelines had identified
130 mg/dl as a borderline LDL-C level
and 160 mg/dl as a high level. A desirable
level of HDL-C was previously defined as at
least 35 mg/dl. (See accompanying table.) For
more information on the new NCEP cholesterol
guidelines you may want to visit this
section of the NHLBI Web site:
http://www.nhlbi.nih.gov/guidelines/cholesterol/atp_iii.htm.
The NCEP guidelines also call for more
aggressive monitoring of people with “borderline”
LDL-C levels. A physician’s initial
intervention for a person in the borderline
category would typically be lifestyle modification.
The number of Americans receiving
recommendations increases from 52 to 65
million with the new guidelines. Lifestyle
modifications designed to promote a healthy
lipid profile include reduction of dietary fat,
increase of soluble dietary fiber and increase
in physical activity, as well as weight loss and
smoking cessation, if indicated.
As a result of the new recommendations, more people with borderline profiles may
find their physicians recommending that
they begin taking a cholesterol-lowering
medication, in addition to lifestyle modifications.
The new recommendations increase
this number from 13 to 36 million
Americans. The medications typically used
to lower cholesterol belong to a drug category
known as HMG-CoA reductase inhibitors,
or “statins,” because they end with the suffix
“-statin.” Commonly used drugs in this category
include atorvastatin (Lipitor), cerivastatin
(Baycol), lovastatin (Mevacor),
pravastatin (Pravachol), and simvastatin
( Zocor). Statins are typically prescribed with
the goal of lowering LDL-C. They work by
inhibiting cholesterol synthesis and increasing
the number of LDL receptors in the liver.
They also have a modest effect of increasing
HDL-C and lowering triglycerides (TC).
While statins have a clear benefit, they
can also have adverse effects, a risk with any
effective therapy. Common side effects
include myositis (muscle inflammation),
arthralgias (joint pains), GI upset and elevated
liver function tests. Physicians typically
obtain liver enzyme levels before starting a
patient on a statin medication and monitor
those levels throughout therapy. Because animal
studies have shown an increase in birth
defects, statins are not appropriate medications
to take during pregnancy.
Additionally there is some concern that
statin medications deplete levels of certain
natural substances that are beneficial, such as
coenzyme Q-10 (CoQ10), a heart protective
substance that is made in the liver. For this
reason many people on statin therapy often
take supplements of CoQ10 as well.
What Else Can You Do?
If your physician is concerned about your
lipid profile, you should be too. There are
several steps you may want to take before
beginning statin therapy or in addition.
Anyone with an elevated LDL-C and an HDL-C
that is less than optimal would be wise to
make any and all lifestyle modifications that
apply. As mentioned earlier, these include
increasing fiber and reducing
dietary fat, which would lower LDL-C, and increasing
physical activity, which is
known to raise HDL-C. If
you smoke, you need to
quit. If you have diabetes,
tight glucose control can
also aid your lipid profile.
While you will certainly
benefit from a heart-healthy
meal plan, it is wise to be
skeptical of fad diets. They
are often designed more for
the benefit of the developer’s
pocketbook than for your health and they
often are too stringent for a reasonable person
to follow for long. When perusing a diet
ask yourself, “Could I stay on this plan for
the next five or ten years?” If the answer is
“no,” keep looking. In avoiding bad fats (animal
fat and saturated plant fats—i.e. palm
oil and trans fatty acids—margarine) don’t be
afraid of the good fats: nuts, fish and other
sources of omega-3 fatty acids. These can
help you to achieve a good lipid profile. Red
wine is protective, as is red grape juice,
because the flavinoids protect against the
oxidative damage from LDL-C. Soy protein
has also been shown to lower LDL-C.
Some supplements can lower cholesterol,
too. As you probably know, niacin supplements
(vitamin B3) have been used since the
1950s, particularly for lowering triglycerides.
While immediate-release niacin is associated
with flushing, the likelihood of flushing is
much less with sustained-release formulations.
However the risk of liver toxicity
increases with sustained release formulations.
Other side effects are nausea and difficulty
with blood sugar control, making it less
attractive for diabetics.
Whether vitamin E supplementation is
beneficial is in question. Several recent studies
have shown no relationship between vitamin
E supplementation and the prevention
of cardiovascular mortality. However, future
studies that take into account the bioavailability
of vitamin E and appropriate dosages
may yield different results. It works because
of its antioxidant protection. Since it is fat
soluble it is incorporated directly into the
LDL-C molecule, helping prevent oxidative
damage at the site of plaque formation.
Folic acid (vitamin B9) is known to lower
homocysteine levels, as does vitamin B12,
vitamin B6 and betaine. Since elevated homocysteine
levels are associated with heart disease
and increased rate of atherosclerosis, it
would be wise to include these in any heart
healthy plan.
Garlic has also been shown to lower LDL-C
and increase HDL-C. The sulfur-containing
substances in garlic help inhibit HMG-CoA
reductase. Garlic is best used as fresh garlic, as
the preparations are somewhat ineffective.
Prolonged cooking and drying destroys the
sulfur-containing compounds that are
thought to be beneficial. The equivalent of
one clove per day is sufficient. Since garlic has
some antithrombotic activity, it is not recommended
for patients taking anticoagulants
(i.e. Coumadin).
Pantethine: Known to Increase HDL-Cholesterol
If you want to improve your lipid profile, you
may want to consider supplements of pantethine.
Remember the goal is not just lower
cholesterol but a healthy profile overall. This
includes LDL-C levels of 100 mg/dl or lower,
TG of 150 mg/dl or lower and HDL-C levels of
at least 40 mg/dl.
Pantethine has been used for the past 30
years in Japan, where it is approved as a pharmaceutical
agent for the purpose of increasing
HDL-C. Pantethine is sold as a supplement in
the United States. This water-soluble component
of coenzyme A is a derivative of pantothenic
acid (vitamin B5). Pantethine has a
greater capacity to lower cholesterol than the
vitamin itself. It is a colorless or light yellow
substance that is soluble in water and alcohol
and is usually taken as a tablet. Pantethine
works by slowing production of cholesterol in
the liver and boosting the rate at which one’s
metabolism uses fats. It significantly reduces
levels of TC and LDL-C while raising HDL-C. It
is the most effective natural product against
serum TG levels. Pantethine is not known to
cause significant side effects, has no known
drug interactions and may be the best choice
for diabetics. It has not been known to cause
birth defects.
In a recent multicenter study daily doses of
600 mg pantethine were associated with
increases averaging approximately 7 mg/dl in
HDL-C, as well as moderate decreases in LDL-C
and TG. In addition to taking several other
heart-healthy steps, you may want to add pantethine
to the tools you use for improving
your lipid profile.
Where to Get Quality Pantethine
In order to get the best results from
pantethine supplements you need to take a
total of 600 to 900 mg daily, in two to three
separate doses. Since the supplement industry
is self-regulated, as a consumer you need to be
cautious about how supplements are manufactured
and whether they are what they claim to
be. Daiichi Pharmaceutical Co., based in
Japan, is the largest producer of pantethine in
the world. They sell their own pantethine
product here in North America as an ingredient
to the dietary supplement industry under
the name Pantesin™. Pantesin is manufactured
by Daiichi’s own proprietary process.
The result is a consistent, high-quality product.
If a pantethine-based dietary supplement
product includes the name Pantesin, you can
be assured that you are buying a supplement
made with the highest quality, pharmaceuticalgrade
pantethine available in the market today.
Supplements are just that. They do not
replace adequate exercise and a healthy diet.
To learn more about the role of fat in the
body, visit the NCEP Web site (listed
earlier). Ask your doctor if cholesterol
screening is appropriate for you and use the
knowledge you gain to live a heart-healthy
lifestyle, adding supplements, and if needed,
medication.
Cathleen London, M.D. is a board certified family physician. Dr. London is a clinical instructor at Boston University in the Department of Family Medicine. She is also an assistant professor at Tufts University School of Medicine. She earned her medical degree from Yale University and completed
her residency in family practice at Oregon Health Sciences University. Her premedical requirements were completed at Stanford University.
Dr. London believes in a holistic approach to health care which utilizes a combination of Western, allopathic medicines, diet and lifestyle modification and herbal medicines when appropriate.
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