What is CHOLESTEROL?
Cholesterol is a waxy, fat-like substance found in body
cells of humans and animals. Sometimes cholesterol is referred
to as "good" cholesterol and "bad" cholesterol. Actually these
descriptions refer to the substances, called lipoproteins, that
carry cholesterol throughout the body in the bloodstream.
Lipoproteins are a combination of varying amounts of fats and
proteins.
What is "good" cholesterol?
"Good" cholesterol is associated with high density
lipoproteins (HDLs). HDLs are believed to remove excess
cholesterol from the body, therefore higher levels of HDLs are
also believed to be associated with lower rates of heart disease.
What is "bad" cholesterol?
"Bad" cholesterol is associated with low density
lipoproteins (LDLs). LDLs carry cholesterol in the blood to body
cells. High levels of LDLs are usually associated with an
elevated blood cholesterol and an increased risk of heart disease
due to cholesterol and fat being deposited in the arteries.
These fatty deposits decrease the interior size of the arteries
so the blood supply is reduced, thus increasing the risk of heart
disease and stroke.
How can HDL and LDL levels be controlled?
There is no proven way to control HDL and LDL levels, but
diet may play a part. Current studies are also showing that
exercise may increase "good" cholesterol levels in some
individuals.
Where does cholesterol come from?
Cholesterol in the body comes from two major sources. Foods
of animal origin, such as meat, milk, and eggs, are one source.
The other major source of cholesterol is that which is produced
by the body, the majority of which comes from the liver.
What does cholesterol do in the body?
Cholesterol is required for the formation of bile acids
which are needed for fat digestion. It is also used to make
important hormones such as estrogen and progesterone and is
involved in the formation of Vitamin D in the skin.
What are the effects of excessive cholesterol and fats in the
diet?
Much controversy exists about fat, cholesterol and heart
disease. Some medical experts believe that consumption of high
levels of saturated fat and cholesterol lead to high blood
cholesterol and, in turn, to an increased risk of heart disease.
Yet, other experts state that there is still no proof that
reducing consumption of cholesterol will effectively reduce the
incidence of heart disease. Other factors that have been
strongly implicated in heart disease are stress, high blood
pressure, smoking, obesity, diabetes, and a family history of
heart disease.
How does dietary fat influence cholesterol?
To protect your heart, experts recommend that you reduce
your overall fat intake - a measure considered by many to be
even more important than eating less cholesterol. About 30% of
our calories should come from fats. Many North Americans and
Europeans get 40% of their calories from fat. Another protective
measure involves replacing some of the saturated fats you now
consume with polyunsaturated fats found in vegetables and fish.
Saturated fats raise cholesterol levels in the blood while
polyunsaturated fats lower them. Although it was once believed
that monounsaturated fats had no effect on blood cholesterol
levels, recent research studies suggest that a diet high in
monounsaturated fatty acids is effective in reducing LDL levels
while keeping HDL levels the same.
Dietary fats are made up of three types of fatty acids:
saturated, monounsaturated and polyunsaturated. Fats containing
a large amount of saturated fatty acids are hard at room
temperature; less saturated fats are soft or liquid at room
temperature. Thus, beef fat is more saturated than chicken fat
and vegetable shortening is more saturated than vegetable oil.
The table, below, shows the fatty acid composition of a
number of food fats.
Type of Fat
(%-Polyunsaturated %-Saturated %-Monounsaturated)
Animal Fats
Butterfat 66 30 4
Beef tallow 52 44 4
Pork (lard) 38 46 7
Vegetable Oils
Coconut 92 6 1
Palm kernel oil 86 12 2
Palm oil 51 39 10
Cottonseed 28 21 50
Peanut 21 50 28
Margarine, soft 18 36 36
Margarine, stick 17 59 25
Sesame 15 40 40
Corn 14 28 55
Soybean 14 21 50
Olive 14 75 7
Sunflower 10 21 64
Safflower 7 17 71
Canola 6 62 32
How can cholesterol and saturated fat intake be lowered?
1. Avoid high cholesterol foods such as.............
Egg yolk 213 mg
Shrimp (3 1/2 oz., cooked) 96 mg
Beef liver (4 oz., cooked) 500 mg
Butter (1 tablespoon) 31 mg
Whole milk (1 cup) 35 mg
Cheddar or Swiss Cheese (1 oz.) 28 mg
Cottage cheese, 4% (1/2 cup) 17 mg
2. Include lower cholesterol foods such as...........
Egg white 0 mg
Egg substitute 0 mg*
Fish (4 oz., cooked) 75-100 mg
Beef, pork or lamb (4 oz., cooked) 100-115 mg
Veal (4 oz., cooked) 145 mg
Poultry (4 oz., cooked) 90-110 mg
Dried beans and peas 0 mg
All vegetables and fruits 0 mg
Margarine (1 tablespoon, all veg. oil) 0 mg
Skim milk (1 cup) 5 mg
Cottage cheese, dry curd (1/2 cup) 6 mg
*Some egg substitutes do contain cholesterol. Check the label to
be sure!
3. Select lean cuts of meat.
4. Serve moderate portion sizes.
5. Replace animal fats with appropriate substitutes.
Remember, cholesterol is found only in animal products. Plant
foods (fruits, vegetables, and grains) have no cholesterol unless
animal fats are added in preparation or seasoning.
(Compiled by Sue Snider, Ph.D. and Anita Wehrman, B.S., R.D.)