Tuesday, July 7, 2009

Vegetarian Diet

American Dietetic Association Endorses Vegetarian Diets
by Laurie Barclay

July 6, 2009 — Vegetarian diets, if well-planned, are healthful and nutritious for all age groups and can help prevent and treat chronic diseases, according to an updated position paper released by the American Dietetic Association. The revised recommendations are published in the July issue of the Journal of the American Dietetic Association. The position was adopted by the House of Delegates Leadership Team in 1987 and was reaffirmed in 1992, 1996, 2000, and 2006; the updated position paper is to remain in effect until December 31, 2013.

"Common reasons for choosing a vegetarian diet include health considerations, concern for the environment, and animal welfare factors," write Winston J. Craig, PhD, MPH, RD, from Andrews University in Berrien Springs, Michigan, and Ann Reed Mangels, PhD, RD, LDN, FADA, from the Vegetarian Resource Group in Baltimore, Maryland. "Vegetarians also cite economic reasons, ethical considerations, world hunger issues, and religious beliefs as their reasons for following their chosen eating pattern.... Individual assessment is required to accurately evaluate the nutritional quality of the diet of a vegetarian or a self-described vegetarian."

Defining and Planning a Vegetarian Diet

The American Dietetic Association defines a vegetarian diet, or lacto-ovo vegetarian diet, as one that does not include meat, fowl, seafood, or products containing those foods. The lacto-vegetarian diet also excludes eggs and primarily consists of grains, vegetables, fruits, legumes, seeds, nuts, and dairy products. The vegan, or total vegetarian, eating pattern excludes eggs, dairy, and other animal products. Within these broad definitions, there is still variation in the degree to which animal products are excluded.

A well-planned vegetarian diet can meet current recommendations for all vital nutrients, including protein, omega-3 fatty acids, iron, zinc, iodine, calcium, and vitamins D and B-12. However, use of supplements or fortified foods may be helpful to boost intake of important nutrients in certain cases.

The American Dietetic Association contends that carefully planned vegetarian diets, including vegan diets, are healthful and nutritionally sufficient for individuals of all ages, including pregnant or lactating women, infants, children, adolescents, and athletes. During pregnancy, adherence to a nutritionally adequate vegetarian diet can lead to positive health outcomes for both the mother and infant.

Furthermore, well-constructed vegetarian diets may offer health benefits in terms of preventing and treating certain chronic diseases, including heart disease, cancer, obesity, and diabetes. Vegetarian diets are linked to lower risk for death from ischemic heart disease, according to findings of an evidence-based review. In addition, low-density lipoprotein cholesterol levels, blood pressure, and body mass index appear to be lower in vegetarians than in nonvegetarians, as do rates of hypertension, type 2 diabetes, and cancer.

The position paper also reviews available evidence concerning the effects of vegetarian diets on cardiovascular disease, obesity, osteoporosis, renal disease, dementia, diverticulitis, and rheumatoid arthritis.

Specific vegetarian considerations regarding specific nutritional programs are also reviewed, including the Special Supplemental Nutrition Program for Women, Infants, and Children; child nutrition programs; feeding programs for elderly adults; corrections facilities programs; military and armed forces programs; and other institutions and quantity food service organizations.

During the next decade, the number of vegetarians in the United States is expected to increase. Vegetarian diets are typically characterized by certain healthful features that may lower the risk for chronic disease — notably, reduced consumption of saturated fat and cholesterol and increased consumption of fruits, vegetables, whole grains, nuts, soy products, fiber, and phytochemicals with potent antioxidant, antiproliferative, and cancer-protective activity.

However, individual diets should be evaluated to ensure that they are nutritionally adequate, given the variability of dietary habits among vegetarians. Other important roles for food and nutrition professionals are to educate vegetarians regarding sources of key nutrients, food purchase and preparation, and individual dietary modifications to meet their specific requirements.

Recommendations for a Healthy Diet

Specific recommendations to help ensure that vegetarians have healthful diets with sufficient nutrients are as follow:

•The diet should contain a wide variety of healthful foods, including whole grains, vegetables, fruits, legumes, nuts, and seeds, as well as dairy and eggs if desired.
•Consumption of foods that are high in sugar, sodium, and fat, particularly saturated fat and trans-fatty acids, should be minimized.
•The diet should contain a wide range of healthful fruits and vegetables.
•For vegetarians who consume dairy products and eggs, moderation is recommended, as well as use of lower-fat dairy products.
•A regular source of vitamin B-12 is recommended, as well as of vitamin D if sunlight exposure is limited.
•Nutritionists should be able to recommend local, reliable sources for purchase of vegetarian foods, or mail order sources in some communities where suitable local sources are unavailable.
•To facilitate meeting nutrient needs on a vegetarian diet, clinicians should collaborate with family members, especially the parents of children following vegetarian diets.
•Practitioners unfamiliar with the principles of vegetarian nutrition should help their vegetarian patients find a nutritionist or other qualified provider to advise them regarding their diet.
"It is the position of the American Dietetic Association that appropriately planned vegetarian diets, including total vegetarian or vegan diets, are healthful, nutritionally adequate, and may provide health benefits in the prevention and treatment of certain diseases," the position paper authors write. "Well-planned vegetarian diets are appropriate for individuals during all stages of the lifecycle, including pregnancy, lactation, infancy, childhood, and adolescence, and for athletes.... Food and nutrition professionals can assist vegetarian clients by providing current, accurate information about vegetarian nutrition, foods, and resources."

J Am Diet Assoc. 2009;109:1266–1282.

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