Vegetarian diets are not just a trend; they’ve long been a staple of human dietary patterns. The Academy of Nutrition and Dietetics’ 2016 position paper on vegetarian diets states “appropriately planned vegetarian, including vegan, diets are healthful, nutritionally adequate and may provide health benefits for the prevention and treatment of certain diseases. These diets are appropriate for all stages of the life cycle, including pregnancy, lactation, infancy, childhood, adolescence, older adulthood and for athletes.”
Vegetarian diets are defined by the Academy as being devoid of animal flesh, fish and seafood. However, there are some variations including lacto-vegetarian, ovo-vegetarian or lacto-ovo vegetarian which are diets that include dairy, eggs or both, respectively. Vegan diets do not contain any animal flesh, fish, seafood, dairy or eggs and also exclude honey.
Not only do these plant-based diets have a long history throughout human evolution, they continue to be popular today.
The International Food Information Council Foundation listed plant-based eating as one of the five food trends to watch in 2019, citing that sales in this food category have grown 20 percent since 2017. IFIC also notes the increased sales of plant-based milk and meat alternatives, as well as a 2018 Food and Health Survey stating that 70 percent of respondents reported believing plant-based protein sources are healthful, compared to only 40 percent who reported believing animal protein sources are healthful. To understand why plant-based diets are so popular, let’s look back at how they’ve progressed over time.
|Types of Vegetarian Diets|
|Vegetarian||May or may not include egg or dairy products|
|Lacto-ovo-vegetarian||Includes eggs and dairy products|
|Lacto-vegetarian||Includes dairy products but not egg products|
|Ovo-vegetarian||Includes eggs and egg products, but no dairy|
|Vegan||Excludes eggs and dairy products, and may exclude honey|
|Raw vegan||Based on vegetables, fruit, nuts and seeds, legumes and sprouted grains. The amount of uncooked food varies from 75% to 100%.|
|Source: Position of the Academy of Nutrition and Dietetics: Vegetarian Diets © 2016 by the Academy of Nutrition and Dietetics|
The Trouble with Terminology
Some consumers attribute a negative connotation to veganism, citing it as restrictive or elitist.
The terms “plant-based” or “plant-forward” may be more inclusive to consumers but both present the challenge of not having a set definition, even among nutrition professionals.
If the literal definition is used, a plant-based diet simply is a diet in which the foundation is made from plants. Given it is not called “vegetarian” or “vegan,” it could imply that meat, poultry or fish could be included in this type of diet, though it would likely be less of an emphasis than plant foods.
Vegetarianism throughout History
The first known group to abstain from eating meat in hopes of achieving longevity, as well as for philosophical reasons, were Pythagoreans — followers of the Greek philosopher Pythagoras (6th century B.C.). Inspired by these original teachings, Greek philosopher Porphyry authored a book in the 3rd century A.D. called On Abstinence from Animal Food, capturing the dietary pattern and ethics of Greek philosopher Plotinus. There also is evidence of ancient vegetarianism in the Maurya Dynasty (304 to 232 B.C.), when Buddhist vegetarian advocate Indian Emperor Ashoka encouraged people to care for animals in an attempt to stop animal sacrifice. Additionally, ancient Japanese Emperor Tenmu banned people from eating wild animal meat in the Tang Dynasty (675 A.D.).
In the 1400s, Leonardo da Vinci famously became a vegetarian; in the 1700s, Benjamin Franklin did as well. These are just two of several influential figures to advocate for a meatless diet.
In the late 1800s, John Harvey Kellogg advocated for a vegetarian diet to improve the health of the U.S. population. As the medical director of the Battle Creek Sanitarium, a Seventh Day Adventist health institution, Kellogg was a huge influence on Lenna Frances Cooper, a nursing graduate who was appointed chief dietitian in 1906 and, in 1913, published her first book, The New Cookery, based on vegetarian recipes served at the Sanitarium. In 1917, Cooper co-founded the Academy (then American Dietetic Association) and served as its 14th president in 1937. Since 1962, the Academy has honored this founding member with the annual Lenna Frances Cooper Memorial Lecture Award at the Food & Nutrition Conference & Expo™.
Vegetarian Nutrition and Dietary Guidelines
Meat was part of the ancient human diet, though at much lower levels than today, especially in industrialized nations. Although there is evidence that ancient humans hunted and consumed meat after the last ice age 10,000 to 12,000 years ago, based on art and bones collected, it would have been difficult to harvest enough meat to feed growing populations, especially as populations increased rapidly during the world’s agricultural revolution.
In ancient Greece, eating meat was mostly celebratory and estimates of animal-based intake in European agricultural societies were just 5 to 10 kilograms per person per year. Current consumption in industrialized countries is estimated to be 88 to 100 kilograms per person per year.
The first Dietary Guidelines for Americans were released in 1980. MyPlate guidelines, which are based on the 2015- 2020 Dietary Guidelines for Americans, include information to create a balanced vegetarian eating pattern to meet nutritional needs. Guidelines state that vegetarians can get enough protein if the variety and amounts of foods consumed are adequate.
Examples of protein foods for vegetarians include eggs and milk products (for lactoovo-vegetarians), beans and peas, nuts and nut butters, and soy products. Other tips for vegetarians include information on how to get enough plant-based sources of iron, calcium, zinc and vitamin B12. Previously, vegetarian guidelines were included in the 2010-2015 Dietary Guidelines. This earlier version was less thorough in how to balance a vegetarian diet and instead instructed on how to substitute the same amount of plant foods for meat options. New guidelines include changes in food group composition and portion amounts for vegetarians.
Future Trends in Vegetarian Nutrition
Retail experts predict the future of plant-based diets includes both meat and dairy alternatives, as well as cultured meat, and that tofu- and seitan-based meat replacements may continue rising in popularity. Vegan meat replacements that actually mimic meat’s texture and flavor also are forthcoming, with several products already on the market. Consumer trends point to the fact that interest continues to increase and money spent on plant-based products climbs each year. As interest grows, registered dietitian nutritionists in any area of practice can benefit from understanding plant-based nutrition as well as being able to counsel patients and clients on plant-based eating.
RDNs can support clients who are interested in a vegetarian diet by providing evidence for improved outcomes in many chronic diseases and information on the appropriateness of a well-planned vegetarian or vegan diet. This includes ensuring vegan clients consume a reliable source of B12, such as fortified foods or dietary supplements, to meet their needs since no plant foods are a reliable source of naturally occurring vitamin B12. Other potential nutrients to analyze in the diet include omega-3 fatty acids, iron, zinc, calcium, iodine and vitamin D.
|Plant-Based Diets Through the Years|
|Early Medieval Period/500 B.C.: Orphic and Pythagorean adherents take a philosophical stance against eating animals. This also may have been driven by the desire for longevity.Maurya Dynasty/304-232 B.C.: Buddhist vegetarian advocate Indian Emperor Ashoka encourages people to care for animals, attempting to stop animal sacrifice.
300 A.D.: Philosopher Porphyry authors On Abstinence from Animal Food based on philosopher Plotinus’ continuation of Pythagoras’ dietary philosophy.
Tang Dynasty/675 A.D.: Japanese Emperor Tenmu bans people from eating wild animal meat.
Late 1400s: Leonardo da Vinci follows a vegetarian diet.
1720s: 16-year-old Benjamin Franklin reads English merchant and vegetarian advocate Thomas Tyron’s Wisdom’s Dictates and becomes a vegetarian for part of his life.
Late 1700s: Utilitarian philosopher Jeremy Bentham asks about the ethics of consuming animals: “The question is not can they reason? Nor can they talk? But can they suffer?”
1809: The Bible Christian Church, a vegetarian church, is founded in England.
1817: The Bible Christian Church is established in Philadelphia.
1843: Bronson Alcott, father of Louisa May Alcott, establishes a vegan commune in Harvard, Mass., called Fruitlands.
1847: First vegetarian society founded in Ramsgate, England.
1850: First vegetarian society founded in New York City.
Late 1800s: John Harvey Kellogg advocates for a vegetarian lifestyle.
|1901: Lenna Frances Cooper graduates from Battle Creek Sanitarium in nursing and works under vegetarian medical director Kellogg.
1906: Upton Sinclair writes The Jungle, depicting unsanitary practices in the meat packing industry and driving more people toward a vegetarian diet.
1906: Cooper is appointed Chief Dietitian at Battle Creek Sanitarium.
1910: Seventh Day Adventist minister E.G. Fulton publishes The Vegetarian Cookbook.
1913: Cooper publishes her first book, The New Cookery, featuring vegetarian recipes.
1917: Cooper co-founds the American Dietetic Association.
1937: Cooper serves as ADA’s 14th president.
1947: The American Vegetarian Party supports naturopathic doctor John Maxwell in the 1948 presidential election. The group nominated candidates in every election until 1964.
1962: ADA’s first Lenna Frances Cooper Memorial Lecture Award is presented.
1970s: Australian moral philosopher Peter Singer’s Animal Liberation begins the modern animal rights movement.
1971: American researcher Frances Moore Lappé writes Diet for a Small Planet.
1972: American writer Anna Thomas writes The Vegetarian Epicure.
1992: The Academy (formerly ADA) forms Vegetarian Nutrition dietetic practice group due to interest from members.
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