Vegetarians do not eat meat, poultry, or fish (people who include small amounts of these
foods in their diets sometimes call themselves semi-vegetarians.) Vegetarians build their
diets around a wide variety of plant foods, including grains (such as rice,
barley, and oats), grain-based foods (such as
bread, pasta, and cereals),
legumes, vegetables, fruits,
nuts and seeds. Soy foods such as tofu, soy
milk, and soy-based meat substitutes play
an important role in many vegetarian diets. In addition, cheese and milk made from rice,
almonds, and soybeans are prominent in some vegetarian diets. Lacto-ovo vegetarians
consume dairy foods and eggs. Vegans are vegetarians who do not eat any animal
products, including dairy products, eggs, and honey.
Why do people follow this diet?
People choose vegetarian diets for a variety of reasons. Many choose them to improve their
health or to decrease the risk of chronic diseases, such as heart disease, diabetes, or cancer. Others go vegetarian due to concerns about
world hunger and the environment, because large-scale production of animal foods uses land
that could otherwise be used to grow plant-based foods, and is a major cause of deforestation
and soil erosion worldwide. Still others are concerned about the presence of antibiotics,
hormones, pesticide residues or disease-causing agents (as with mad cow disease) that may be
present in meat. Some vegetarians object to inhumane practices of modern-day animal farming,
so their reasons for being vegetarian are largely ethical. Some vegetarians believe that
humans are not physiologically suited to meat eating; humans have more in common with
herbivorous animals than with carnivorous animals in terms of the structure and function of
the digestive tract. Finally, some people choose vegetarianism in an attempt to live more
simply and economically, and in closer harmony with the way most of the world’s
What do the advocates say?
It is well documented that vegetarians are healthier than people who eat meat. In some
cases, vegans have better health than lacto-ovo vegetarians. Although many vegetarians also
exercise and avoid smoking, evidence indicates that their good health is largely due to diet.
One study of 30,000 people in California compared vegetarians and meat eaters who, aside from
their dietary differences, had very similar lifestyles and health practices. The vegetarians
were less likely to be obese, or to have high blood pressure, diabetes,
rheumatoid arthritis, or colon cancer.
They were also less likely to die from heart
disease. In fact, the vegetarians were healthier even than people who ate meat only
occasionally. Even when vegetarians were fatter than meat eaters, the vegetarians had lower
Vegetarians have lower blood pressure even when they eat the same amount of salt as meat
eaters and exercise less. Researchers have known since the beginning of the 1900s that feeding
meat to vegetarians causes their blood pressure to rise.
Many studies show that vegetarians have less colon cancer than meat eaters. The composition
of bacterial flora in the colon differs between vegetarians and people who eat meat in ways
that could possibly affect cancer risk.
Many factors in vegetarian diets contribute to the better health of vegetarians. These
- Vegetarians consume two to three times as much fiber as do meat-eaters. This may help to reduce cholesterol and blood glucose levels, and protect
against colon cancer.
- Vegetarians consume more antioxidants,
which are found in a wide variety of plant foods. Antioxidants protect cells from
oxygen-induced damage and reduce the risk for heart disease, arthritis, cancer, and other
- Vegetarians consume more phytochemicals than do meat eaters, special compounds found in
plants. Many phytochemicals have a wide range of protective effects in the human body. They
help to detoxify carcinogens, stimulate the immune system, regulate cell growth (which helps
to fight cancer), and reduce some of the harmful effects of excessive exposure to
- Vegetarians eat more isoflavones than do meat eaters. These compounds, found mostly in soy foods, are another type of phytochemical.
Research shows that isoflavones may reduce the risk for prostate cancer and may improve bone health.
- Vegetarians consume much less saturated fat and cholesterol than do meat eaters. This
helps to explain why they have significantly lower levels of blood cholesterol. One study
showed that blood cholesterol levels were 14% lower in lacto-ovo vegetarians and 35% lower in
vegans compared to meat-eaters. Lower intakes of saturated fat reduce the risk for heart disease and possibly for diabetes and cancer.
- Vegetarians do not consume heme iron, a
type of iron found in meat that may increase the risk of heart disease and cancer.
- Vegetarians do not eat red meat, which has been linked to increased cancer risk in many
studies. Red meat consumption stimulates the production of mutation-causing compounds in the
colon and is linked to increased damage to DNA.
What do the critics say?
Critics of vegetarianism claim that people who choose this diet will have to “balance
incomplete proteins” to synthesize complete protein in the body. Proteins that come from
fruits, vegetables, legumes, and grain products are only “incomplete” in
the sense that they do not provide all nine essential amino acids (protein building blocks) at a single
meal; thus, according to critics, a vegetarian (and especially a vegan) must be careful to
consume appropriate quantities of complementary proteins each day to ensure that he or she is
getting enough dietary protein.
Contrary to this popular belief, inadequate protein intake is rarely a concern for
vegetarians. Better understanding of protein nutrition shows that, for adults, it is not
necessary to consume special combinations of foods to meet requirements for the right balance
of amino acids. Many plant foods, such as grains and legumes, provide protein. Soy foods and dairy products are particularly rich in high-quality
protein. Protein needs are easily met when vegetarians consume a variety of plant foods and
eat enough food to meet calorie needs.
Critics also point out that there is no way to get vitamin B12 via food except through animal products.
Tempeh and other fermented soy products do not
contain consistent enough quantities of B12 to meet the body’s requirements. Vegetarians
must therefore eat B12-fortified foods or take vitamin supplements on a daily basis to prevent
Some critics fault vegetarian, and particularly vegan, diets for not providing sufficient
calcium. In truth, most people, not just
vegetarians, eat less than optimal amounts of calcium. Dairy products are a good source of
dietary calcium, but they are not the only source. Green leafy vegetables and tofu are also
good sources, and are usually eaten in large quantities by vegetarians. Vegans—who eat
no animal products—are the most likely to suffer from calcium deficiency. Many
Americans—vegetarians and meat eaters alike—could benefit from taking a calcium
Vegetarians eat less iron than
non-vegetarians, and the iron they eat is somewhat less absorbable. As a result, vegetarians
are more likely to have reduced iron stores. However, iron deficiency is not usually caused by a lack of
iron in the diet alone; an underlying cause—such as iron loss in menstrual
blood—often exists. Although iron is found in a variety of different foods, its
availability to the body (bioavailability) varies significantly. This is determined by whether
it is found in the form of heme and non-heme iron. Heme iron is found only in meat,
fish, and poultry. It is absorbed much more readily than non-heme iron found primarily in
fruits, vegetables, dried beans,
nuts, and grain products, such as bread and iron-fortified breakfast cereals. Including a source of vitamin C at each meal improves absorption of
Strict vegans may become iodine deficient
if they do not consume enough iodine, readily available in iodized salt.
Very few foods are good sources of vitamin
D, which is why milk is fortified with it.
Vegetarians who do not consume milk should be sure to get 20 to 30 minutes of sun exposure
every day since this promotes the synthesis of vitamin D in the body. People who live in
cloudy, smoggy, or northern areas, and people who do not leave their residences, need foods
fortified with vitamin D. These fortified foods include breakfast cereals and some brands of
soy milk and rice milk. Since people with dark skin make vitamin D
less efficiently, they may also need supplemental sources of vitamin D or increased sun
Are there any groups or books?
The Vegetarian Resource Group
PO Box 1463
Baltimore, MD 21203
211 Indian Drive
Pittsburgh, PA 15238
Physicians Committee for Responsible Medicine
PO Box 6322
Washington, DC 20015
The Vegetarian Nutrition and Health Letter
1711 Nichol Hall
School of Public Health
Loma Linda University
Loma Linda, CA 92350
The Vegetarian Way: Total Health for You and Your Family by
Virginia Messina and Mark Messina. New York: Crown Trade Paperbacks, 1996.
Becoming Vegetarian: The Complete Guide to Adopting a Healthy
Vegetarian Diet by Vesanto Melina, Brenda Davis, and Victoria Harris. Summertown, TN:
Book Publishing Co., 1995.
Being Vegetarian for Dummies by Suzanne Havala. New York:
Hungry Minds, Inc., 2001.
Simply Vegan: Quick Vegetarian Meals by Debra Wasserman and
Reed Mangels. Baltimore, MD: Vegetarian Resource Group, 1999.
Lorna Sass’ Complete Vegetarian Kitchen: Where Good Flavors
and Good Health Meet by Lorna J. Sass. New York: Hearst Books, 1995.
Vegetarian Cooking for Everyone by Deborah Madison. New
York: Broadway Books, 1997.
May All Be Fed: A Diet for a New World by John Robbins and
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