From: wheeler@super.org (Ferrell S. Wheeler)
Subject: Re: Does vegetarian get enough nutrition from food?
Keywords: vegetarian
Organization: Supercomputing Research Center (Bowie, MD)
Date: Wed, 9 Sep 1992 19:02:41 GMT


VEGETARIAN FOODS: POWERFUL FOR HEALTH

     A vegetarian diet has been advocated by everyone from philosophers, such
as Plato and Nietzsche, to statesmen, such as Benjamin Franklin, to modern
pop icons such as Paul McCartney and Bob Marley. Science is also on the
side of vegetarian foods. A multitude of studies have proven the health
benefits of a vegetarian diet to be remarkable.
     "Vegetarian" is defined as avoiding all animal flesh, including fish and
poultry. Vegetarians who avoid flesh, but do eat animal products such as
cheese, milk, and eggs are ovo-lacto-vegetarians (ovo = egg; lacto = milk,
cheese, etc.). The ranks of those who eschew all animal products are
rapidly growing; these people are referred to as pure vegetarians or vegans
(vee' guns). Scientific research shows that ovo-lacto-vegetarians are
healthier than meat-eaters, and vegans are healthier than ovo-lacto-
vegetarians.

* Preventing Cancer
     A vegetarian diet helps to prevent cancer. Numerous epidemiological and
clinical studies have shown that vegetarians are nearly fifty percent less
likely to die from cancer than non-vegetarians.1 Similarly, breast cancer
rates are dramatically lower in nations, such as China, that follow plant-
based diets. Interestingly, Japanese women who follow Western-style, meat-
based diets are eight times more likely to develop breast cancer than women
who follow a more traditional plant-based diet.2 Vegetarians also have lower
rates of colon cancer than meat-eaters.3
                                       Animal products are usually high
in fat and always devoid of fiber. Meat and dairy products contribute to
many forms of cancer, including cancer of the colon, breast, prostate, and
other organs. Colon cancer has been directly linked to meat consumption.
High-fat diets also encourage the body's production of estrogens, in
particular, estradiol. Increased levels of this sex hormone have been
linked to breast cancer. One recent study linked dairy products to an
increased risk of ovarian cancer. The process of breaking down the lactose
(milk sugar) into galactose evidently damages the ovaries.4
     Vegetarians avoid the animal fat that is linked to cancer and get
abundant fiber and vitamins that help to prevent cancer. In addition, blood
analysis of vegetarians reveals a higher level of Natural Killer Cells,
specialized white blood cells that attack cancer cells.5

* Beating Heart Disease
     Vegetarian diets also help prevent heart disease. Animal products are the
main source of saturated fat and the only source of cholesterol in the
diet. Vegetarians avoid these risky products. Additionally, fiber helps
reduce cholesterol levels6, and animal products contain no fiber. One study
even demonstrated that a low-fat, high-fiber, plant-based diet combined
with stress reduction techniques, smoking cessation, and exercise could
actually reverse atherosclerosis~hardening of the arteries.7 Heart diets
that include animal products are much less effective, usually only slowing
the process of atherosclerosis.

* Lowering Blood Pressure
     Back in the early 1900's, nutritionists noted that people who ate no meat
had lower blood pressure.8 It was also discovered that vegetarian diets
could, within two weeks, significantly reduce a person's blood pressure.9
These results were evident regardless of the sodium levels in the
vegetarian diets.

* Preventing and Reversing Diabetes
     Non-insulin-dependent (adult-onset) diabetes can be better controlled and
sometimes even eliminated through a low-fat, vegetarian diet along with
regular exercise. Because such a diet is low in fat and high in fiber and
complex carbohydrates, it allows insulin to work more effectively. The
diabetic person can more easily regulate glucose levels. While a vegetarian
diet cannot eliminate the need for insulin in people with insulin-dependent
(childhood-onset) diabetes, it can often reduce the amounts of insulin
used. Some scientists believe that insulin dependent diabetes may be caused
by an auto-immune reaction to dairy proteins.

* Gallstones, Kidney Stones, and Osteoporosis
     Vegetarian diets have been shown to reduce one's chances of forming
kidney stones and gallstones. Diets that are high in protein, especially
animal protein, tend to cause the body to excrete more calcium, oxalate,
and uric acid. These three substances are the main components of urinary
tract stones. British researchers have advised that persons with a tendency
to form kidney stones should follow a vegetarian diet.10 Similarly, high-
cholesterol, high-fat diets~the typical meat-based diet~are implicated in
the formation of gallstones.
     For many of the same reasons, vegetarians are at a lower risk for
osteoporosis. Since animal products force calcium out of the body, eating
meat can promote bone loss. In nations with mainly vegetable diets (and
without dairy product consumption), osteoporosis is less common than in the
U.S.~even when calcium intake is also less than in the U.S.11

* Asthma
     A 1985 Swedish study demonstrated that asthmatics who practice a vegan
diet for a full year have a marked decrease in their need for medications,
and in their frequency and severity of asthma attacks. Twenty-two of the
twenty-four subjects reported improvement by the end of the year.12 Dairy
allergies may be part of the reason.

* Common Concerns
     Some people still worry about the ease with which a vegetarian diet can
provide all essential nutrients. The fact is, it is very easy to have a
well-balanced diet with vegetarian foods. Vegetarian foods provide plenty
of protein. Careful combining of foods is not necessary. Any normal variety
of plant foods provides more than enough protein for the body's needs.
Although there is somewhat less protein in a vegetarian diet than a meat-
eater's diet, this is actually an advantage. Excess protein has been linked
to kidney stones, osteoporosis, and possibly heart disease and some
cancers. A diet focused on beans, whole grains, and vegetables contains
adequate amounts of protein without the "overdose" most meat-eaters get. 
     Calcium is easy to find in a vegetarian diet. Many dark, green, leafy
vegetables and beans are loaded with calcium, and some orange juices and
cereals are calcium-fortified. Iron is plentiful in whole grains, beans,
and fruits.

* Vitamin B12
     Vitamin B12 is a genuine issue for vegans, although very easy to deal
with. Traditionally, getting this vitamin has not been difficult. In
cultures with plant-based diets, the microorganisms that produce B12 grow
in the soil and cling to root vegetables, and traditional Asian miso and
tempeh contain large amounts of the vitamin. But with industrialized
production and improved hygiene, this source of B12 has been eliminated.
Meat-eaters get B12 through microorganisms living in the animals they eat.
     Although cases of B12 deficiency are very uncommon, it is important to
make sure that one has a reliable source of the vitamin. Good sources
include all common multiple vitamins (including vegetarian vitamins),
fortified cereals, and fortified soy milk. It is especially important for
pregnant women and breast-feeding mothers to get enough vitamin B12.

* Special Concerns: Pregnancy, Infants, and Children
     During pregnancy, one's nutritional needs increase. The American Dietetic
Association has found vegan diets adequate for fulfilling nutritional needs
during pregnancy, but pregnant women and nursing mothers should supplement
their diets with vitamins B12 and D. Most doctors also recommend that
pregnant women supplement their diet with iron and folic acid, although
vegetarians normally consume more folic acid than meat-eaters.
     Vegetarian women have a lower incidence of pre-eclampsia in pregnancy,
and significantly more pure breast milk. Analyses of vegetarians' breast
milk show that the levels of environmental contaminants in their milk are
much lower than in non-vegetarians.13 Studies have also shown that in
families with a history of food allergies, when women abstain from
allergenic foods, including milk, meat, and fish, during pregnancy, they
are less likely to pass allergies on to the infant.14 Mothers who drink milk
pass cow antibodies along to their nursing infants through their breast
milk. These antibodies can cause colic.
     Vegetarian children also have high nutritional needs, but these, too, are
met within a vegetarian diet. A vegetarian menu is "life-extending." As
young children, vegetarians may grow more gradually, reach puberty somewhat
later, and live substantially longer than do meat-eaters. Do be sure to
include a reliable source of vitamin B12. 

* Further Reading
For more information on vegetarian diets, PCRM recommends:
     The Power of Your Plate, by Neal Barnard, MD
     The McDougall Plan, by John McDougall, MD
     Dr. Dean Ornish's Program for Reversing Heart Disease, by Dean Ornish,
MD.

References:

1. Phillips RL. Role of lifestyle and dietary habits in risk of cancer
among Seventh-Day Adventists. Cancer Res (Supple) 1975;35:3513-22.
2. Trichhopoulos D, Yen S, et al. The effect of Westernization on urine
estrogens, frequency of ovulation, and breast cancer risks: a study in
ethnic Chinese women in the Orient and in the U.S.A. Cancer 1984;53:187-92.
3. Phillips RL, 1975. 
4. Cramer DW, Willett WC, et al. Galactose consumption and metabolism in
relation to the risk of ovarian cancer. The Lancet 1989;2:66-71.
5. Malter M, Schriever G, Eilber U. Natural killer cells, vitamins, and
other blood components of vegetarian and omnivorous men. Nutrition and
Cancer 1989;12:271-278.
6. Sacks FM, et al. Plasma lipids and lipoproteins in vegetarians and
controls. New Engl J Med 1975;292:1148-52.
7. Ornish D, Brown SE, et al. Can lifestyle changes reverse coronary heart
disease? The Lancet 1990;336:129-33.
8. Salie F. Influence of vegetarian food on blood pressure. Med Klin
1930;26:929-931.
9. Donaldson AN. The relation of protein foods to hypertension. Calif West
Med 1926;24:328-331.
10. Robertson WG, Peacock M, et al. Should recurrent calcium oxalate stone
formers become vegetarians? British J Urology 1979;51:427-431.
11. Hegsted DM. Calcium and osteoporosis. J Nutr 1986;116:2316-2319.
12. Lindahl O, Lindwall L, et al. Vegan regimen with reduced medication in
the treatment of bronchial asthma. J Asthma 1985;22:45-55.
13. Hergenrather J, Hlady G, et al. Pollutants in breast milk of
vegetarians (letter). New Engl J Med 1981;304:792.
14. Allergies in infants are linked to mother's diets. New York Times, 30
August 1990.

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