Vegetarian Diets: The Plusses and the Pitfalls
by Dixie Farley

Many people are attracted to vegetarian diets. It's no wonder.

Health experts for years have been telling us to eat more plant foods and      
less fat, especially saturated fat, which is found in larger amounts in        
animal foods than plant foods.

C. Everett Koop, M.D., former surgeon general of the Public Health Service,    
in his 1988 Report on Nutrition and Health, expressed "major concern ...       
[about Americans'] disproportionate consumption of foods high in fats, often   
at the expense of foods high in complex carbohydrates and fiber--such as       
vegetables, fruits, and whole-grain products--that may be more conducive to    
health."

And, while guidelines from the U.S. departments of Agriculture and Health and  
Human Services advise 2 to 3 daily servings of milk and the same of foods      
such as dried peas and beans, eggs, meat, poultry and fish, they recommend 3   
to 5 servings of vegetables, 2 to 4 of fruits, and 6 to 11 servings of bread,  
cereal, rice, and pasta--in other words, 11 to 20 plant foods, but only 4 to   
6 animal foods.
 
It's wise to take precautions, however, when adopting diets that entirely      
exclude animal flesh or dairy products.

"The more you restrict your diet, the more difficult it is to get all the      
nutrients you need," says Marilyn Stephenson, R.D., of the Food and Drug       
Administration's Center for Food Safety and Applied Nutrition. "To be          
healthful, vegetarian diets require very careful, proper planning. Nutrition   
counseling can help you get started on a diet that is nutritionally adequate."

Certain people, such as Seventh-day Adventists, choose a vegetarian diet       
because of religious beliefs. Others give up meat because they feel that       
eating animals is unkind. Some people believe it's a better use of the         
Earth's resources to eat low on the food chain; the North American Vegetarian  
Society notes that 1.3 billion people could be fed with the grain and          
soybeans eaten by U.S. livestock. On the practical side, many people eat       
plant foods because animal foods are more expensive.

"I'm a vegetarian because I just plain enjoy the taste of vegetables and       
pasta," says Judy Folkenberg of Bethesda, Md. Reared on a vegetarian diet      
that included eggs and dairy products, Folkenberg added fish to her diet five  
years ago. "I love crab cakes and shrimp," she says.

Just as vegetarians differ in their motivation, their diets differ as well.    
(See box.) In light of these variations, it's not surprising that the exact    
number of vegetarians is unknown. In a National Restaurant Association Gallup  
Survey in June 1991, 5 percent of respondents said they were vegetarians, yet  
2 percent said they never ate milk or cheese products, 3 percent never ate     
red meat, and 10 percent never ate eggs.

Risks

Vegetarians who abstain from dairy products or animal flesh face the greatest  
nutritional risks because some nutrients naturally occur mainly or almost      
exclusively in animal foods.

Vegans, who eat no animal foods (and, rarely, vegetarians who eat no animal    
flesh but do eat eggs or dairy products), risk vitamin B12 deficiency, which   
can result in irreversible nerve deterioration. The need for vitamin B12       
increases during pregnancy, breast-feeding, and periods of growth, according   
to Johanna Dwyer, D.Sc., R.D., of Tufts University Medical School and the New  
England Medical Center Hospital, Boston. Writing in 1988 in the American       
Journal of Clinical Nutrition, Dwyer reviewed studies of the previous five     
years and concluded that elderly people also should be especially cautious     
about adopting vegetarian diets because their bodies may absorb vitamin B12    
poorly.

Ovo-vegetarians, who eat eggs but no dairy foods or animal flesh, and vegans   
may have inadequate vitamin D and calcium. Inadequate vitamin D may cause      
rickets in children, while inadequate calcium can contribute to risk of        
osteoporosis in later years. These vegetarians are susceptible to iron         
deficiency anemia because they are not only missing the more readily absorbed  
iron from animal flesh, they are also likely to be eating many foods with      
constituents that inhibit iron absorption--soy protein, bran, and fiber, for   
instance. Vegans must guard against inadequate calorie intake, which during    
pregnancy can lead to low birth weight, and against protein deficiency, which  
in children can impair growth and in adults 
can cause loss of hair and muscle mass and abnormal accumulation of fluid.

According to the Institute of Food Technologists and the American Dietetic     
Association, if appropriately planned, vegan diets can provide adequate        
nutrition even for children. Some experts disagree.

Gretchen Hill, Ph.D., associate professor of food science and human nutrition  
at the University of Missouri, Columbia, believes it's unhealthy for children  
to eat no red meat.

"My bet is those kids will have health problems when they reach 40, 50 or 60   
years of age," she says, "mostly because of imbalances with micronutrients     
[nutrients required only in small amounts], particularly iron, zinc and        
copper." While meat is well-known as an important source of iron, Hill says    
it may be even more valuable for copper and zinc. Copper not only helps build  
the body's immunity, it builds red blood cells and strengthens blood vessels.  
"A lot of Americans are marginal in this micronutrient," she says, "and, as a  
result, are more susceptible to diseases. Children can't meet their zinc       
needs without eating meat."

Also, vegetarian women of childbearing age have an increased chance of         
menstrual irregularities, Ann Pedersen and others reported last year in the    
American Journal of Clinical Nutrition. Nine of the study's 34 vegetarians     
(who ate eggs or dairy foods) missed menstrual periods, but only 2 of the 41   
non-vegetarians did. The groups were indistinguishable when it came to         
height, weight and age at the beginning of menstruation.

Can Veggies Prevent Cancer?

The National Cancer Institute states in its booklet Diet, Nutrition & Cancer   
Prevention: The Good News that a third of cancer deaths may be related to      
diet. The booklet's "Good News" is: Vegetables from the cabbage family         
(cruciferous vegetables) may reduce cancer risk, diets low in fat and high in  
fiber-rich foods may reduce the risk of cancers of the colon and rectum, and   
diets rich in foods containing vitamin A, vitamin C, and beta-carotene may     
reduce the risk of certain cancers.

Part of FDA's proposed food labeling regulations, published in the Nov. 27,    
1991, Federal Register, states, "The scientific evidence shows that diets      
high in whole grains, fruits, and vegetables, which are low in fat and rich    
sources of fiber and certain other nutrients, are associated with a reduced    
risk of some types of cancer. The available evidence does not, however,        
demonstrate that it is total fiber, or a specific fiber component, that is     
related to the reduction of risk of cancer."

As for increasing fiber in the diet, Joanne Slavin, Ph.D., R.D., of the        
University of Minnesota, in 1990 in, gives this advice: "Animal studies show   
that soluble fibers are associated with the highest levels of cell             
proliferation, a precancerous event. The current interest in dietary fiber     
has allowed recommendations for fiber supplementation to outdistance the       
scientific research base. Until we have a better understanding of how fiber    
works its magic, we should recommend to American consumers only a gradual      
increase in dietary fiber from a variety of sources."

FDA acknowledges that high intakes of fruits and vegetables rich in            
beta-carotene or in vitamin C have been associated with reduced cancer risk.   
But the agency believes the data are not sufficiently convincing that either   
nutrient by itself is responsible for this association.

Pointing out that plant foods' low fat content also confers health benefits,   
FDA states in its proposed rule that diets low in fat give protection against  
coronary heart disease and that it has tentatively determined, "Diets low in   
fat are associated with the reduced risk of cancer."

FDA notes that diets high in saturated fats and cholesterol increase levels    
of both total and LDL cholesterol, and thus the risk for coronary heart        
disease, and that high-fat foods contribute to obesity, a further risk factor  
for heart disease. (The National Cholesterol Education Program recommends a    
diet with no more than 30 percent fat, of which no more than 10 percent comes  
from saturated fat.)

For those reasons, the agency would allow some foods to be labeled with        
health claims relating diets low in saturated fat and cholesterol to           
decreased risk of coronary heart disease and relating diets low in fat to      
reduced risk of breast, colon and prostate cancer. "Examples of foods          
qualifying for a health claim include most fruits and vegetables; skim milk    
products; sherbets; most flours, grains, meals, and pastas (except for egg     
pastas); and many breakfast cereals," the proposed rule states.

Dwyer, in her article, summarizes these plant food benefits:

"Data are strong that vegetarians are at lesser risk for obesity, atonic       
[reduced muscle tone] constipation, lung cancer, and alcoholism. Evidence is   
good that risks for hypertension, coronary artery disease, type II diabetes,   
and gallstones are lower. Data are only fair to poor that risks of breast      
cancer, diverticular disease of the colon, colonic cancer, calcium kidney      
stones, osteoporosis, dental erosion, and dental caries are lower among        
vegetarians."

Death rates for vegetarians are similar or lower than for non-vegetarians,     
Dwyer reports, but are influenced in Western countries by vegetarians'         
"adoption of many healthy lifestyle habits in addition to diet, such as not    
smoking, abstinence or moderation in the use of alcohol, being physically      
active, resting adequately, seeking ongoing health surveillance, and seeking   
... guidance when health problems arise."

Slow Switching

It's generally agreed that to avoid intestinal discomfort from increased       
bulk, a person shouldn't switch to foods with large amounts of fiber all at    
once. A sensible approach to vegetarian diets is to first cut down on the      
fattiest meats, replacing them with cereals, fruits and vegetables,            
recommends Jack Zeev Yetiv, M.D., Ph.D., in his book Popular Nutritional       
Practices: A Scientific Appraisal. "Some may choose to eliminate red meat but  
continue to eat fish and poultry occasionally, and such a diet is also to be   
encouraged."

Changing to the vegetarian kitchen slowly also may increase the chances of     
success.

"If you suddenly cut out all animal entr}es from your diet, it's easy to get   
discouraged and think there's nothing to eat," says lifelong veggie-eater      
Folkenberg. "I build my meals around a starchy carbohydrate such as pasta or   
potatoes. Even when I occasionally cook seafood, I center on the               
carbohydrate, making that the larger portion. Shifting the emphasis from       
animal to plant foods is easier after you've found recipes you really enjoy."

Because vegans and ovo-vegetarians face the greatest potential nutritional     
risk, the Institute of Food Technologists recommends careful diet planning to  
include enough calcium, riboflavin, iron, and vitamin D, perhaps with a        
vitamin D supplement if sunlight exposure is low. (Sunlight activates a        
substance in the skin and converts it into vitamin D.)

For these two vegetarian groups, the institute recommends calcium supplements  
during pregnancy, infancy, childhood, and breast-feeding. Vegans need to take  
a vitamin B12 supplement because that vitamin is found only in animal food     
sources. Unless advised otherwise by a doctor, those taking supplements        
should limit the dose to 100 percent of the National Academy of Sciences'      
Recommended Dietary Allowances.

Vegans, and especially children, also must be sure to consume adequate         
calories and protein. For other vegetarians, it is not difficult to get        
adequate protein, although care is needed in small children's diets.

Nearly every animal food, including egg whites and milk, provides all eight    
of the essential amino acids in the balance needed by humans and therefore     
constitutes "complete" protein. Plant foods contain fewer of these amino       
acids than animal foods.

The American Dietetic Association's position paper on vegetarian diets,        
published in its journal in 1988 and co-authored by Dwyer and Suzanne Havala,  
R.D., states that a plant-based diet provides adequate amounts of amino acids  
when a varied diet is eaten on a daily basis. The mixture of proteins from     
grains, legumes, seeds, and vegetables provide a complement of amino acids so  
that deficits in one food are made up by another. Not all types of plant       
foods need to be eaten at the same meal, since the amino acids are combined    
in the body's protein pool.

Frances Lappe, in Diet for a Small Planet, writes that to gain the greatest    
use of all the amino acids, it's best to consume complementary proteins        
within three to four hours. High amounts of complete proteins can be gained    
by combining legumes with grains, seeds or nuts.

Also available are various protein analogs. These substitute "meats"--usually  
made from soybeans--are formed to look like meat foods such as hot dogs,       
ground beef, or bacon. Many are fortified with vitamin B12.

The accompanying chart lists sources of the nutrients of greatest concern for  
vegetarians who don't eat animal foods.

As with any diet, it's important for the vegetarian diet to include many       
different foods, since no one food contains all the nutrients required for     
good health. "The wider the variety, the greater the chance of getting the     
nutrients you need," says FDA's Stephenson.

The American Dietetic Association recommends:
- minimizing intake of less nutritious foods such as sweets and fatty foods
- choosing whole or unrefined grain products instead of refined products
- choosing a variety of nuts, seeds, legumes, fruits, and vegetables,          
including good sources of vitamin C to improve iron absorption
- choosing low-fat varieties of milk products, if they are included in the     
diet 
- avoiding excessive cholesterol intake by limiting eggs to two or three       
yolks a week
- for vegans, using properly fortified food sources of vitamin B12, such as    
fortified soy milks or cereals, or taking a supplement
- for infants, children and teenagers, ensuring adequate intakes of calories   
and iron and vitamin D, taking supplements if needed
- consulting a registered dietitian or other qualified nutrition               
professional, especially during periods of growth, breast-feeding, pregnancy,  
or recovery from illness
- if exclusively breast-feeding premature infants or babies beyond 4 to 6      
months of age, giving vitamin D and iron supplements to the child from birth   
or at least by 4 to 6 months, as your doctor suggests
- usually, taking iron and folate (folic acid) supplements during pregnancy.

With the array of fruits, vegetables, grains, and herbs available in U.S.      
grocery stores and the availability of vegetarian cookbooks, it's easy to      
devise tasty vegetarian dishes.

People who like their entr}es on the hoof also can benefit from adding more    
plant foods to their diets. You don't have to be a vegetarian to enjoy dishes  
from a vegetarian menu.

Dixie Farley is a staff writer for FDA Consumer.
Vegetarian Varieties

The Institute of Food Technologists, in the July 1991 issue of its journal,    
Food Technology, describes six types of vegetarians. They are listed here by   
degree of exclusion of animal foods and by the foods included in the diet:
- semi-vegetarian--dairy foods, eggs, chicken, and fish, but no other animal   
flesh
- pesco-vegetarian--dairy foods, eggs, and fish, but no other animal flesh
- lacto-ovo-vegetarian--dairy foods and eggs, but no animal flesh
- lacto-vegetarian--dairy foods, but no animal flesh or eggs
- ovo-vegetarian--eggs, but no dairy foods or animal flesh
- vegan--no animal foods of any type.

--D.F.
Replacing Animal Sources of Nutrients

Vegetarians who eat no meat, fish, poultry, or dairy foods face the greatest   
risk of nutritional deficiency. Nutrients most likely to be lacking and some   
non-animal sources are:
- vitamin B12--fortified soy milk and cereals
- vitamin D--fortified margarine and sunshine
- calcium--tofu, broccoli, seeds, nuts, kale, bok choy, legumes (peas and      
beans), greens, calcium-enriched grain products, and lime-processed tortillas
- iron--legumes, tofu, green leafy vegetables, dried fruit, whole grains, and  
iron-fortified cereals and breads, especially whole wheat (absorption is       
improved by vitamin C, found in citrus fruits and juices, tomatoes,            
strawberries, broccoli, peppers, dark-green leafy vegetables, and potatoes     
with skins)
- zinc--whole grains (especially the germ and bran), whole-wheat bread,        
legumes, nuts, and tofu.

As all plant foods--including fruit--contain some protein, by eating a         
variety of fruits, vegetables and grains, even vegans probably can get enough  
of this nutrient. To improve the quality of protein and ensure getting enough:
                                   Combine
legumes such as black-eyed peas, chickpeas, peas, peanuts, lentils, sprouts,   
and black, broad, kidney, lima, mung, navy, pea, and soy beans
                                     with
grains such as rice, wheat, corn, rye, bulgur, oats, millet, barley, and       
buckwheat.


There are also foods made to look like meats (protein analogs) such as hot     
dogs, sausage, and bacon.