Gabe Mirkin, M.D.
No. Your blood cholesterol level is influenced far more
by how many calories and how much saturated and partially
hydrogenated fat you eat, than by how much cholesterol is in
your food. Cholesterol is found only in foods from animals, such
as meat, fish, chicken, dairy products and eggs. It is not found in
plants. More than 80 percent of the cholesterol in your body is
made by your liver. Less than 20 percent comes from the food
that you eat. When you eat more cholesterol, your liver makes
less.
Your liver makes cholesterol from saturated fats, which
are found in most foods but are concentrated in meat, poultry
and whole-milk dairy products. The saturated fat is broken down
by your liver into acetone units. If you are not taking in too many
calories, your liver uses the acetone units for energy, but if you
are taking in more calories than your body needs, your liver uses
these same acetone units to manufacture cholesterol. That
explains why eating two eggs a day does not raise blood
cholesterol levels in the average American. They are already
taking in so much cholesterol from meat, fish and chicken and
diary products, that when they take in more, they absorb less.
The average North American takes in 350 mg per day of
cholesterol. If he takes in 26 mg per day, he absorbs 41 percent.
When he takes in 188 mg cholesterol per day, he absorbs only
36 percent, and when he takes in 421 mg per day (the equivalent
of two eggs), he absorbs only 25 percent. Some people absorb
more than five times as much as other people at the same
intake. So you lower blood cholesterol levels far more effectively
by eating less food, less saturated fat and less partially
hydrogenated fats than by avoiding foods that contain
cholesterol.
November 20, 2005