Manual of Clinical Nutrition Management A- 36 Copyright © 2013 Compass Group, Inc.
VEGETARIAN DIETS
Description
A vegetarian is a person who does not eat meat, including fowl or seafood, or products containing these foods (1).
A wide spectrum of dietary practices is considered vegetarian (1). A vegetarian whose diet consists of foods of
plant origin only is a total vegetarian or vegan. However, many vegetarians also consume eggs (ovovegetarian),
dairy products (lactovegetarian), or both eggs and dairy products (lacto-ovovegetarian). The two most common
definitions for vegetarian diets in the research are vegan diets, which are devoid of all flesh foods, and vegetarian
diets, which are devoid of all flesh foods but do include eggs, dairy products, or both (Grade II)* (1). According to the
Academy of Nutrition and Dietetics Evidence Analysis Library, these broad categories mask important variations
within vegetarian diets. Thus, the absolute categorization of vegetarian dietary practices is difficult and may
result in unclear relationships between vegetarian diets and other health factors (Grade II) (1).
Indications
Vegetarian diets are adopted for a variety of health, ecological, economical, philosophical, and ethical reasons (1).
Vegetarian diets offer a number of health advantages, including lower blood cholesterol levels, lower blood
pressure levels, and lower risks of hypertension, heart disease, and type 2 diabetes (1). Vegetarians tend to have
a lower body mass index and lower overall cancer rates (1). Vegetarian diets tend to be lower in saturated fat and
cholesterol and have higher levels of dietary fiber, magnesium, potassium, folate, antioxidants (eg, vitamins C and
E), carotenoids, flavonoids, and other phytochemicals (1). These nutritional differences may explain some of the
health advantages of a varied, balanced vegetarian diet (1). Many epidemiologic studies suggest a positive
relationship between vegetarian lifestyles and reduced risks of several chronic degenerative diseases, such as
ischemic heart disease (Grade I)* (1), coronary artery disease, hypertension, type 2 diabetes, obesity, renal disease,
and some cancers (1).
Nutritional Adequacy
Vegan, lactovegetarian, ovovegetarian and lacto-ovovegetarian diets are healthful and nutritionally adequate
when appropriately planned for all stages of the life cycle, including pregnancy and lactation (1). Appropriately
planned vegan, lactovegetarian, ovovegetarian and lacto-ovovegetarian diets will meet the nutrient needs of
infants, children, and adolescents to support and promote normal growth and development (1-3).
A vegetarian diet can be planned to meet the Dietary Reference Intakes (DRIs) as outlined in Section IA:
Statement on Nutritional Adequacy. Vegans and some other vegetarians may have lower intakes of vitamins B 12
and D, calcium, zinc, long-chain n-3 fatty acids, and occasionally iron (1). The greater production and access to
fortified and enriched foods is making it easier for vegetarians to improve their intake of these key nutrients. All
vegetarians should have a reliable source of vitamin B 12 and vitamin D. If sun exposure is limited, vitamin D
supplements or fortified foods should be emphasized (1-6).
Results of evidence-based analysis suggest that vegetarian diets can be nutritionally adequate in pregnancy
and can lead to a positive birth outcome (7). The nutrient and energy needs of pregnant and lactating vegetarian
women do not differ from those needs of nonvegetarian women with the exception of higher iron
recommendations for vegetarians (1). In addition to iron, key nutrients to assess in pregnancy include vitamin
B 12 , vitamin D, and folate, whereas key nutrients in lactation include vitamin B 12 , vitamin D, calcium, and zinc (1).
Breast-fed infants whose mothers do not have an adequate intake of vitamin B 12 should receive a vitamin B 12
supplement (1,4). In addition, the zinc intake of breast-fed infants should be carefully assessed; zinc supplements
or zinc-fortified foods should be used when complementary foods are introduced if the diet is low in zinc or
mainly consists of foods with low zinc bioavailability (1). Because of the variability of dietary practices among
vegetarians, the individual assessment of dietary intakes is necessary (1).
How to Order the Diet
Order as “Regular Diet – Vegetarian.” The patient’s particular dietary constraints will be considered.
Planning the Diet
A vegetarian diet can be made nutritionally adequate by careful planning and giving consideration to the
following guidelines (1):
Choose a variety of foods, including fruits, vegetables, whole grains, legumes, nuts, seeds, tofu or other soy
products, and, if desired, dairy products and eggs.
Choose whole or unrefined grain products whenever possible, instead of refined products.