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Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL 35294, E-mail: weinsier{at}shrp.uab.edu
Dear Sir:
After reading the proceedings of the Third International Congress on Vegetarian Nutrition in the September 1999 supplement to the Journal (1), I came to the following conclusion: the term vegetarian ought to be removed from the scientific literature. It has many nonnutritional connotations and provides too little specificity about one's dietary pattern.
In the 1940s and 1950s, avoidance of meat was often assumed to be due to religious belief; such eating habits made no other sense in those days. In the 1960s and 1970s, a person who did not eat meat was assumed to be part of the antiestablishment movement and to be using diet to make a political statement. Since the 1980s, avoiding meat has been more likely to be considered part of a healthy lifestyle, although motives unrelated to health are often suspected. As described by Johnston and Sabaté (2), through the years vegetarians have been questioned, ridiculed, and considered to be eccentrics. Although an increasing number of people are now avoiding meat, the label vegetarian carries with it various, and varying, connotations about beliefs and practices that are unrelated to diet and health and that appear to be based in part on societal norms and expectations.
From a scientific standpoint, nutritional investigators too often use the term vegetarian as though it describes a specific dietary pattern. Even dictionaries do not provide consistency in their definitions. Dorland's Medical Dictionary defines vegetarians as those who eat a diet of exclusively vegetable origin, whereas The American Heritage Dictionary states that such persons sometimes include dairy products; Merriam-Webster indicates that animal products are sometimes included. Chefs know full well the lack of specificity of the term when they try to respond to a request for a vegetarian meal. There are even odds that the meal will include fish or cheese, and that it will include fruit for dessert (apparently, vegetarians are assumed to avoid added sugars as well). Among friends and colleagues who consider themselves vegetarians, I have observed many variations on the theme. A few are vegans who eat primarily fruit, vegetables, and whole grains with no added fat, sugar, or honey; yet another eats little fruit and vegetables but large amounts of refined starches, fat, and sugar. It is common for some self-proclaimed vegetarians to eat chicken and for others to avoid chicken and eat fish or dairy products. In an attempt to add more specificity in the scientific literature, various qualifying terms have been used, such as pescovegetarian and lactoovovegetarian. For one person I know who considers himself a vegetarian, an appropriate label might be lactoovopescopoulo-steak-only-when-I-eat-out vegetarian. In the proceedings of the Third International Congress on Vegetarian Nutrition I found reference to 2 new terms that can be added to the list of nonspecific terminology: semivegetarian and near-vegetarian.
In most reports in the proceedings, the authors avoided reference to the term vegetarian and addressed the health effects of specific foods or food groups, such as fruit, vegetables, whole grains, legumes, and nuts. Among the original research papers, when reference was made to a vegetarian diet, such a diet was usually defined in terms of the specific foods selected so that the reader could discern what the subjects were actually eating. By contrast, I found the description of a vegetarian diet particularly interesting in one of the reports that described an intervention trial comparing the effects of an unrestricted omnivorous diet with a vegetarian diet on symptoms of rheumatoid arthritis (3). The "vegetarian diet" was characterized by its exclusion of animal products—as well as of gluten, refined sugar, citrus fruit, salt, alcohol, and caffeinated beverages. Among the review articles, some of the authors simply dichotomized dietary patterns into vegetarian and nonvegetarian. Frankly, I do not think I could describe a typical vegetarian or nonvegetarian diet with enough specificity to be able to even guess about its nutritional adequacy or health effects.
People choose different eating patterns for different reasons. As nutrition scientists and clinicians, we aim to draw conclusions and make recommendations based on the specific foods a person eats. The panel summary paper of Dwyer (4) used the term plant-based diet to describe the general eating pattern of the increasing number of persons who prefer to decrease their consumption of animal foods and to increase their consumption of plant foods. This term still lacks the specificity needed for scientific analysis. However, if we need a descriptive term to broadly categorize this growing dietary pattern, plant-based diet is preferable to vegetarian diet. At least it carries less nonnutritional baggage.
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