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FDA Consumer October 1995
 
More People Trying Vegetarian Diets
 
 by Dixie Farley
 
 Perceiving plant foods as beneficial because they are high in dietary fiber
 and, generally, lower in saturated fat than animal foods, many people turn
 to vegetarian diets.
 
 Grain products, for instance, form the base of the U.S.  Department of
 Agriculture and Department of Health and Human Services' Food Guide
 Pyramid, which recommends 6 to 11 daily servings of bread, cereal, rice,
 and pasta.  Daily intakes advised for other foods are: 3 to 5 servings of
 vegetables; 2 to 4 servings of fruits; 2 to 3 servings of milk, yogurt and
 cheese; and 2 to 3 servings of meat, poultry, fish, dry beans, eggs, and
 nuts.  The guide advises using fats, oils and sweets sparingly.
 
 And, who hasn't seen signs in their grocer's produce section urging
 consumers to eat "5 a day for better health"? This slogan reflects a major
 government-industry campaign to help people eat more fruits and vegetables
 as part of a high-fiber, low-fat diet that emphasizes variety.
 
 The campaign is consistent with the USDA-DHHS Dietary Guidelines for
 Americans, which states: "Many American diets have too many calories and
 too much fat (especially saturated fat), cholesterol, and sodium.  They
 also have too little complex carbohydrates and fiber.  Such diets are one
 cause of America's high rates of obesity and of certain diseases--heart
 disease, high blood pressure, stroke, diabetes, and some forms of cancer."
 
 But health benefits are not the only reason vegetarian diets attract
 followers.
 
 Certain people, such as Seventh-Day Adventists, choose a vegetarian diet
 because of religious beliefs.  Others give up meat because they feel eating
 animals is unethical.  Some believe it's a better use of the Earth's
 resources to eat low on the food chain--that is, to eat plant foods, rather
 than the animals that eat the plant foods.  And many people eat plant foods
 simply because they are less expensive than animal foods.
 
 It's wise to take precautions, however, when adopting a diet that entirely
 excludes animal flesh and dairy products, called a vegan diet.  (See
%"Vegetarian Varieties."`)
 
 "The more you restrict your diet, the more difficult it is to get the
 nutrients you need," says John Vanderveen, Ph.D., director of the Food and
 Drug Administration's Office of Plant and Dairy Foods and Beverages.  "To
 be healthful, vegetarian diets require very careful, proper planning.
 Nutrition counseling can help you get started on a diet that is
 nutritionally adequate."
 
 If appropriately planned, vegan diets, though restrictive, can provide
 adequate nutrition even for children, according to the American Dietetic
 Association and the Institute of Food Technologists.
 
^Plant Food Benefits`
 
 Registered dietitian Johanna Dwyer, of Tufts University Medical School and
 the New England Medical Center Hospital, Boston, 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."
 
 According to Dwyer, vegetarians' longevity is similar to or greater than
 that of non-vegetarians, but is 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."
 
^Can Veggies Prevent Cancer?`
 
 The National Cancer Institute, in its booklet Diet, Nutrition, & Cancer
 Prevention: A Guide to Food Choices, states that 35 percent of cancer
 deaths may be related to diet.  The booklet states:
    - Diets rich in beta-carotene (the plant form of vitamin A) and vitamin
      C may reduce the risk of certain cancers.
    - Reducing fat in the diet may reduce cancer risk and, in helping weight
      control, may reduce the risk of heart attacks and strokes.
    - Diets high in fiber-rich foods may reduce the risk of cancers of the
      colon and rectum.
    - Vegetables from the cabbage family (cruciferous vegetables) may reduce
      the risk of colon cancer.
 
 FDA, in fact, authorized several health claims on food labels relating
 low-fat diets high in some plant-derived foods with a possibly reduced risk
 of cancer.
 
 While FDA acknowledges that high intakes of fruits and vegetables rich in
 beta-carotene or vitamin C have been associated with reduced cancer risk,
 it believes the data are not sufficiently convincing that either nutrient
 by itself is responsible for the association.  Nevertheless, since most
 fruits and vegetables are low-fat foods and may contain vitamin A (as
 beta-carotene) and vitamin C, the agency authorized a health claim relating
 diets low in fat and rich in these foods to a possibly reduced risk of some
 cancers.
 
 Another claim may relate low-fat diets high in fiber-containing vegetables,
 fruits and grains to a possible reduction in cancer risk.  (The National
 Cancer Institute recommends 20 to 30 grams of fiber a day.) Although the
 exact role of total dietary fiber, fiber components, and other nutrients
 and substances in these foods is not fully understood, many studies have
 shown such diets to be associated with reduced risk of some cancers.
 
^Lowering Heart Disease Risk`
 
 FDA also notes that diets high in saturated fats and cholesterol increase
 blood levels of total cholesterol and LDL cholesterol, and thus the risk
 for coronary 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 this reason, the agency
 authorized a health claim relating diets low in saturated fat and
 cholesterol to a possibly reduced risk of coronary heart disease.
 
 Another claim may relate diets low in fat and high in fruits, vegetables,
 and grain products that contain fiber, particularly soluble fiber, to a
 possibly reduced risk of coronary heart disease.  However, the agency
 recognizes that it is impossible to adequately distinguish the effects of
 fiber, including soluble fiber, from those of other food components.
 
 With respect to increasing fiber in the diet, Joanne Slavin, Ph.D., R.D.,
 of the University of Minnesota, in 1990 in Nutrition Today, gives this
 advice: "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."
 
^Precautions`
 
 The American Dietetic Association's position paper on vegetarian diets
 states, "Because vegan diets tend to be high in bulk, care should be taken
 to ensure that caloric intakes are sufficient to meet energy needs,
 particularly in infancy and during weaning." Dwyer and Suzanne Havala, also
 a registered dietitian, updated the paper in the 1993 issue of the
 association's journal.
 
 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 is to slowly increase consumption of grains,
 legumes, seeds, and nuts.  "Some may choose to eliminate red meat but
 continue to eat fish and poultry occasionally, and such a diet is also to
 be encouraged," Jack Zeev Yetiv, M.D., Ph.D., in his book Popular
 Nutritional Practices: A Scientific Appraisal.
 
 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 Vanderveen.
 
 In its position paper on vegetarian diets, the American Dietetic
 Association states that, with a plant-based daily diet, eating a variety of
 foods and sufficient calories for energy needs will help ensure adequate
 intakes of calcium, iron and zinc.  (See%"Replacing Animal Sources of
^Nutrients."`)
 
 The mixture of proteins from grains, legumes, seeds, nuts, and vegetables
 provides 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.
 
 "Soy protein," the paper states, "has been shown to be nutritionally
 equivalent in protein value to proteins of animal origin and, thus, can
 serve as the sole source of protein intake if desired."
 
 The Institute of Food Technologists also recommends careful diet planning
 for vegetarians.  This is especially important when the diet excludes dairy
 foods, to ensure adequate intake of calcium, iron, riboflavin, and vitamin
 D.  For these vegetarians, the institute recommends calcium supplements
 during pregnancy, when breast-feeding, and for infants and children.
 
 The institute and the American Dietetic Association say a vitamin D
 supplement may be needed if sunlight exposure is limited.  (Sunlight
 activates a substance in the skin and converts it into vitamin D.)
 
 They also point out that vegan diets should include a reliable source of
 vitamin B12 (see "Replacing Animal Sources of Nutrients"), because this
 nutrient occurs only in animal foods.  Vitamin B12 deficiency can result in
 irreversible nerve deterioration.
 
 The need for vitamin B12 increases during pregnancy, breast-feeding, and
 periods of growth, Dwyer says.  In a recent issue of Annual Review of
 Public Health, she writes that elderly people also should be especially
 cautious about adopting vegetarian diets because their bodies may absorb
 vitamin B12 poorly.
 
 Unless advised otherwise by a doctor, those taking dietary supplements
 should limit the dose to 100 percent of the U.S.  Recommended Daily
 Allowances.
 
 With the array of fruits, vegetables, grains, and spices available in U.S.
 grocery stores and the availability of vegetarian cookbooks, it's easy to
 devise tasty vegetarian dishes that even non-vegetarians can enjoy.
 
 However, the key to any healthful diet--vegetarian or non-vegetarian--is
 adherence to sound nutrition principles.
 
 _Dixie Farley is a staff writer for FDA Consumer._
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^Vegetarian Varieties`
 
 The American Dietetic Association describes three types of vegetarians.
 They are listed here by the extent to which the diet includes animal foods:
    - lacto-ovo-vegetarian--dairy foods and eggs
    - lacto-vegetarian--dairy foods, but no eggs
    - vegan--no animal foods of any type
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^Replacing Animal Sources of Nutrients`
 
 Vegetarians who eat no animal products need to be more aware of nutrient
 sources.  Nutrients most likely to be lacking and some non-animal sources
 are:
    - vitamin B12--fortified soy beverages and cereals
    - vitamin D--fortified soy beverages and sunshine
    - calcium--tofu processed with calcium, broccoli, seeds, nuts, kale, bok
      choy, legumes (peas and beans), greens, lime-processed tortillas, and
      soy beverages, grain products, and orange juice enriched with calcium
    - 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
    - protein--tofu and other soy-based products, legumes, seeds, nuts,
      grains, and vegetables
 
 _--D.F._
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^American Dietetic Association Recommendations`
 
 For people who follow vegetarian diets, the American Dietetic Association
 has these recommendations:
    - Consult a registered dietitian or other qualified nutrition
      professional, especially during periods of growth, breast-feeding,
      pregnancy, or recovery from illness.
    - Minimize intake of less nutritious foods such as sweets and fatty
      foods.
    - Choose whole or unrefined grain products instead of refined products.
    - Choose a variety of nuts, seeds, legumes, fruits, and vegetables,
      including good sources of vitamin C to improve iron absorption.
    - Choose low-fat or nonfat varieties of dairy products, if they are
      included in the diet.
    - Avoid excessive cholesterol intake by limiting eggs, if they are
      included in the diet, to three or four egg yolks per week.
    - For infants, children and teenagers, ensure adequate intakes of
      calories, vitamin D, calcium, iron, and zinc.  (Intakes of vitamin D,
      calcium, iron, and zinc are usually adequate when a variety of foods
      and sufficient calories are consumed.)
    - If exclusively breast-feeding premature infants or babies beyond 4 to
      6 months of age, give vitamin D and iron supplements to the child from
      birth or at least by 4 to 6 months, as your doctor suggests.
    - Usually, take iron and folate (folic acid) supplements during
      pregnancy.
    - In addition, for vegans:
    - Use properly fortified food sources of vitamin B12, such as fortified
      soy beverages or cereals, or take a supplement.
    - If sunlight is inadequate, take a vitamin D supplement during
      pregnancy or while breast-feeding.
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 FDA Consumer magazine (October 1995)