From wheeler@super.org Wed Feb 24 18:02:25 1993
Date: Thu, 1 Oct 92 10:52:52 EDT
From: wheeler@super.org (Ferrell S. Wheeler)
To: tms@cs.umd.edu
Subject: PCRM Cholesterol



CONTROLLING CHOLESTEROL

     Almost every adult in the industrialized nations develops some degree of
atherosclerosis, commonly known as "hardening of the arteries." In the
United States, many children have fatty streaks, or "pre-atherosclerosis,"
in their arteries. Atherosclerosis leads to strokes, heart attacks, and
other serious problems. But food choices can greatly reduce one's risk of
heart problems.  Heart disease is linked to risk factors. The principal
risk factors are high cholesterol levels, smoking, and high blood pressure.
Others risk factors include: diabetes, obesity, family history of heart
disease, and stress. Here is an overview of how food choices can affect
one's cholesterol level:
     Every animal cell, both human and non-human, contains cholesterol.
Cholesterol is important in some cell functions, and the liver produces all
of the cholesterol the body needs. There is no need to consume any in one's
diet.
     Cholesterol and fats move through the body in protein packages called
lipoproteins. Low density lipoproteins (LDLs) carry cholesterol to the
organs through the arteries. The LDLs deposit their loads through the inner
walls of the arteries. This process encourages the growth of deposits,
called plaques, on the artery walls which narrow the artery and obstruct the
flow of blood. This is atherosclerosis. If the blood flow to the heart is
blocked, a heart attack can occur. If the blood flow to the brain is
blocked, a stroke can occur. Since LDLs promote atherosclerosis, they are
known as "bad cholesterol." The higher the LDL level, the higher the risk
of heart problems.
     "Good cholesterol," found in high density lipoproteins (HDLs), moves back
to the liver where it is disposed of. People who exercise, don't smoke, and
stay at their ideal weight tend to have higher levels of HDLs. Since the
majority of cholesterol is in the form of LDLs, a high blood cholesterol
level means high LDL levels. Blood cholesterol levels are affected by many
factors. But even people with a hereditary tendency toward heart disease can
do something about their cholesterol levels. This is very important because
with every one percent reduction in total blood cholesterol there is about
a two percent reduction in the risk of heart attack.1 Population groups with
an average cholesterol level of 150 or less are largely free of
atherosclerosis. For cholesterol levels above 150, the risk of heart disease
increases.2 The following are some guidelines for lowering blood
cholesterol:

* Decrease Fat Intake, Especially Saturated Fats
     Saturated fats raise cholesterol levels, but they are easy to avoid.
Saturated fats are solid at room temperature. Saturated fats are found
predominately in animal products but are also found in a few vegetable oils
such as palm oil, coconut oil, chocolate, and hydrogenated oils.

* Decrease Cholesterol Intake
     Cholesterol in foods increases levels of LDLs.3 Cholesterol is found only
in animal products. Meat, fish, poultry, dairy products, and eggs all
contain cholesterol, while plant products do not. Choosing lean cuts of meat
is not enough; the cholesterol is mainly in the lean portion. Many people
are surprised to learn that chicken contains as much cholesterol as beef.
Every four-ounce serving of beef or chicken contains 100 milligrams of
cholesterol. Most shellfish are very high in cholesterol. There is no "good
cholesterol" in any food. Cholesterol in foods raises the cholesterol level
in one's blood. The best thing to do is to keep one's fat intake very low
and to avoid all animal products.

* Go Vegan
     As suggested above, basing one's diet on plant foods--grains, beans,
vegetables, and fruits--is the best way to keep saturated fat intake low and
to avoid cholesterol completely. A vegan diet is free of all animal products
and yields the lowest risk of heart disease. One study has shown that people
who adopt a vegetarian diet reduce their saturated fat intake by 26 percent
and achieve a significant drop in blood cholesterol levels in just six
weeks.4 Besides the very low levels of fat eaten in a typical vegetarian
diet, vegetable protein also helps decrease risk for heart disease. Studies
have shown that replacing animal protein with soy protein reduces blood
cholesterol levels even when the total amount of fat and saturated fat in
the diet remain the same.5

* Fiber, the Added Advantage of a Vegetarian Diet
     Soluble fiber helps to slow the absorption of some food components such
as cholesterol. It also acts to reduce the amount of cholesterol the liver
makes. Oats, barley, beans,6 and some fruits and vegetables are all good
sources of soluble fiber. There is no fiber an any animal product.

* Maintain Your Ideal Weight
     Losing weight helps to increase HDL levels (the "good cholesterol"). But
also where one carries excess weight can affect one's risk for heart
disease. People who are thick around the middle ("apple-shaped") are at a
higher risk than those who carry excess weight around the hips and buttocks
("pear-shaped").7 "Apple-shaped" people should lose weight through a low-fat
diet and aerobic exercise.

* Eat Lots of Small Meals
     People who eat frequently throughout the day have lower cholesterol
levels. In one study, men consumed either three meals a day or seventeen
snacks a day. The snackers experienced a reduction in cholesterol levels in
comparison to the three-meal-a-day group.8

* Reduce Stress
     Mental stress causes an increased release of adrenaline which may elevate
blood cholesterol levels. Relaxation techniques such as stretching, deep
breathing, or meditation help in lowering blood cholesterol.

* Exercise
     Aerobic exercise raises levels of HDL-cholesterol and may also reduce
levels of LDLs. Exercise also has other benefits for the heart: it
strengthens the heart muscle, promotes weight loss, and lowers blood
pressure. Exercise can also help reduce stress. Exercise does not have to
be terribly vigorous. A daily half-hour walk is helpful.

* Avoid "Miracle Cures"
     Some people have been promoting fish oil supplements as a means to reduce
blood cholesterol. However, studies show that they do not lower cholesterol
levels. While they may affect triglycerides (fats in the blood), they also
may change the overall pattern of lipoproteins in one's blood in a way that
is not beneficial.9 A diet including fish is not so beneficial as a pure
vegetarian diet.
     There have also been reports that alcohol raises one's levels of HDLs. But
recent studies have shown that alcohol does not raise the type of HDL that
protects against heart disease. Alcohol does add extra calories to the diet
and increases the risk for some forms of cancer.

* Avoid Tobacco
     Tobacco poisons one's heart as well as one's lungs.

* It's All Tied Together
     In order to stop and to reverse atherosclerosis, it is important to take
all of these guidelines to heart. Making only modest changes yields only
modest results. A low-fat, vegetarian diet coupled with exercise, stopping
smoking, and stress reduction programs is the best way to lower one's
cholesterol levels and can even reverse heart disease for many people.10
Well-documented information can be found in Dr. Dean Ornish's Program for
Reversing Heart Disease, by Dean Ornish, MD.

References:
1. National Institutes of Health Consensus Development Conference Statement.
Lowering Blood Cholesterol to Prevent Heart Disease.
2. Pooling Project Resource Group. Relationship of blood pressure, serum
cholesterol, smoking habit, relative weight and ECG abnormalities to
incidence of major coronary events: final report of the Pooling Project. J
Chronic Dis 1978;31:201-306.
3. Johnson C, Greenland P. Effects of exercise, dietary cholesterol, and
dietary fat on blood lipids. Arch Intern Med 1990;150:137-141.
4. Masarei JRL, Rouse IL, et al. Vegetarian diet, lipids and cardiovascular
risk. Aust NZ J Med 1984;14:400-404.
5. Carroll KK, Giovannetti PM, et al. Hypocholesterolemic effect of
substituting soybean protein for animal protein in the diet of healthy young
women. Am J Clin Nutr 1978;31:1312.
6. Swain JF, Rouse IL, et al. Comparison of the effects of oat bran and low-
fiber wheat on serum lipoprotein levels and blood pressure. N Engl J Med
1990;321:929-34.
7. Krotkiewski M, Bjorntorp P, et al. Impact of obesity on metabolism in men
and women: importance of regional adipose tissue distribution. J Clin Invest
1983;72:1150-62.
8. Jenkins DJA, Wolever TMS, et al. Nibbling versus gorging: metabolic
advantages of increased meal frequency. N Eng J Med 1989;321:929-34.
9. Grundy SM, Denke MA. Dietary influences on serum lipids and lipoproteins.
J Lipid Res 1990;31:1149-72.
10. Ornish D, Brown SE, et al. Can lifestyle changes reverse coronary heart
disease? The Lancet 1990;336:129-33.

Physicians Committee for Responsible Medicine
P.O. Box 6322
Washington, DC 20015
(202) 686-2210



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