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The Good, the Bad, and the Ugly about Cholesterol
About two in three adults have a
cholesterol level that is higher than
recommended. Having high cholesterol affects your
heart and blood vessels and
increases your risk of developing
cardiovascular disease (CVD). High cholesterol
causes fatty deposits (known as plaques) to build up inside your blood vessels.
When people mention their cholesterol level, they are usually speaking of
total cholesterol. Your total cholesterol is a combination of all the different
types of cholesterol, the good, the bad, and the ugly.
Lipoproteins, or blood fats, take several forms. The main substances are:
(1) Chylomicrons
(2) HDL (high-density lipoprotein) cholesterol
(3) VLDL (very low density lipoprotein), and
(4) LDL (low-density lipoprotein) cholesterol.
Chylomicrons
Chylomicrons (pronounced ky-low-my-krons) come from the
fats we eat. Because
fats are not well absorbed in their natural state, they need to be converted (or
morphed) into a ore absorbable substance. As fat passes from the stomach into
our small intestines, the enzymatic action of our pancreatic juices and bile
from our liver and gall bladder create chylomicrons by rearranging these fat
molecules and improving digestion.
Chylomicrons contain mostly triglycerides. There are some people with abnormal
chylomicron production, based on genetic problems. They are able to produce
chylomicrons but are unable to also break them down. However, for most of us,
the enzyme lipoprotein lipase breaks down chylomicrons. This enzyme slices off
the fatty acids from the glycerol molecule; then we can use the fatty acids for
energy or store them in our fat cells.
HDL Cholesterol
There are two major forms of HDL cholesterol, referred to as HDL 2 and HDL3.
Both forms protect us against cardiovascular disease. Most laboratories combine
HDL2 and HDL3 counts and refer to the total as just HDL cholesterol.
HDL travels around in your bloodstream, sucking up cholesterol, much like a
biological vacuum cleaner. HDL carries waxy cholesterol away from fatty deposits
on your arteries, to be broken down in the liver. The higher your HDL
cholesterol level, the better the cleaning job and the lower your risk of heart
and blood vessel disease. To help you remember what is good for you, just
remember that you want your high-density lipoprotein cholesterol to be high. The
higher, the better.
VLDL Cholesterol
VLDL cholesterol contains mainly triglycerides, just like chylomicrons. VLDL can
be formed by breaking up chylomicrons or can be manufactured by your liver. Then
these triglyceride-loaded particles can be either transported to the rest of the
body and used as energy, or stored in your
thighs,
waist, derriere, and other
fat depots. Although high VLDL levels are related to coronary heart disease,
they are not as damaging as LDL cholesterol. When VLDL (or chylomicron) levels
increase, high triglyceride levels result and your HDL cholesterol level drops.
This can compound the harm of a high VLDL cholesterol level.
LDL Cholesterol
LDL cholesterol is known as the "bad" cholesterol. Picture a molecule wearing a
black cowboy hat, squeezing your arteries with black gloves, and depositing
globs of yellow fat plaques. LDL cholesterol is a powerful risk factor for
cardiovascular disease. For those without diseased blood vessels, reducing LDL
cholesterol levels below 110 mg /dL will probably improve your ability to avoid
heart disease. However, if you have coronary heart disease, it is recommended
that your LDL cholesterol be lower than 100 mg /dL. At this level, cholesterol
plaques begin to dissolve, and arteries become unobstructed. You want your
low-density lipoprotein cholesterol level to be low. The lower, the better.
Classification of LDL, HDL, and Total
Cholesterol (in mg/dL)
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LDL Cholesterol
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100
Optimal*
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100-129
Near optimal/above optimal
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130-159 Borderline high
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160-189 High
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>190
Very high
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HDL Cholesterol
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<40 Low
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>60 High
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Total Cholesterol
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<200 Desirable
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200-239
Borderline high
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>240 High
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Triglycerides
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<150 Normal
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150-199
Borderline high
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200-499
High
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>500
Very high
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*Optimal LDL goal if you have heart disease, diabetes, or multiple risk
factors.
Excess triglycerides in the blood stream are linked to
coronary heart disease. High levels can be caused by genetic abnormalities,
excessive
fat intake, or uncontrolled metabolic problems such as
diabetes.
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Why Is My Cholesterol Different From Yours?
Our blood fat levels are controlled by many factors:
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What we eat- the more animal protein and
fat we eat (this includes
products made from cow’s milks such as cheese and butter) the more cholesterol
our bodies get.
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The levels of male and female
hormones- Women have the benefit of
estrogen, which increases HDL cholesterol levels and may be responsible for
the fact that women live approximately seven years longer than men. Lowered
estrogen levels after menopause have been linked to higher levels of bad
cholesterol.
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Smoking habits (lowers HDL cholesterol)-
Smoking cigarettes lowers HDL
cholesterol levels, which is one reason it is one of the major risk factors
for heart disease.
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Our weight and percentage of body fat- Excess
body weight tends to increase your LDL cholesterol level. This means that if
you are overweight and have a high LDL-cholesterol level, losing weight may
help you lower it. Weight
loss also helps to lower triglycerides (another type of fat carried in
the bloodstream) and raise HDL ("good") cholesterol levels.
Having
too much fat can increase our chances of having
HBP
due to an increased cholesterol level in addition. Fats and cholesterol
build up always go hand in hand and when these two elements in our body
shoot up above its normal level, the danger is so overwhelming.
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The drugs we take- Certain drugs can worsen our cholesterol and
triglyceride levels, especially diuretics (water pills) and certain blood
pressure and heart medications called beta blockers.
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The amount of exercise we get- Regular physical activity may
lower LDL cholesterol and raise HDL ("good") cholesterol
levels.
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Our heredity- We might not like it, but our heredity - the genes that make
us unique beings-has a giant impact on our cholesterol and triglyceride
levels. Some people have familial cholesterol and triglyceride abnormalities
that, without treatment, can shorten life span and create rapidly progressive
disease. It is important for anyone whose father, mother, or close relative
had heart or blood vessel disease before age 50, to see his or her health care
provider to measure cholesterol and triglyceride levels.
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Stress- Stress
over the long term has been shown in several studies to raise blood
cholesterol levels. One way that stress may do this is by affecting your
habits. For example, when some people are under stress, they console
themselves by eating fatty foods. The
saturated fat and
cholesterol in these foods contribute to higher levels of blood
cholesterol.
Breaking Down Cholesterol and Triglycerides
For greater health, we want our body to break down LDL cholesterol, chylomicrons,
and VLDL (our main triglyceride particles) and create more HDL cholesterol
"vacuum cleaners." Although we often blame our shortcomings on heredity, we can
take the bull by the horns (rather than eat the steer) and lower LDL cholesterol
and triglyceride levels by making wise
dietary choices
(especially how much and
what kind of fat we eat) and supercharging our fat-busting enzymes by losing
excess body fat and getting regular
exercise. The level of fat-metabolizing
enzymes in your body depends, in part, on the amount and type of exercise you
do.
Small amounts of
alcohol (one to two drinks a day) may
raise HDL cholesterol levels; however, higher amounts will increase
triglyceride levels.
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