Vegan vs vegetarian: what each label actually excludes

Vegetarian and vegan are not two points on the same scale invented at the same time. Vegetarian is the older word by nearly a century: the Vegetarian Society of Great Britain formed on 30 September 1847 at a meeting in Ramsgate, and its founders were what we'd now call lacto-ovo vegetarians, eating no flesh but keeping milk and eggs on the grounds that those weren't “flesh.” Vegan is the newer, sharper word, and it was coined on purpose, in a specific room, to mean something the older word didn't cover.

In November 1944, Donald Watson, a woodwork teacher and secretary of the Leicester Vegetarian Society, convened a meeting with five other non-dairy vegetarians, including Elsie Shrigley and George and Fay Henderson. The group had asked the Vegetarian Society to open a section for people who also avoided dairy and eggs, and been turned down. So they left and started their own society. Watson coined “vegan” by taking the first three and last two letters of “vegetarian,” on the logic that veganism was where vegetarianism finished. The new Vegan Society didn't stay a diet club for long: by 1949, member Leslie J. Cross had pushed its founding idea toward the emancipation of animals from exploitation by man, and the definition the society still uses today, adopted in its current form in the winter of 1988, frames veganism as excluding animal exploitation “for food, clothing or any other purpose.” That clause is the whole difference in two words: clothing, and any other purpose.

The labels get used loosely enough in conversation that it's worth laying out what each one rules out, because “vegetarian” alone covers at least four different eating patterns and “plant-based” covers none in particular.

Vegetarianism, in every version above, is a dietary rule: it answers what goes on a fork. Veganism, per the Vegan Society's own definition, is a philosophy that happens to have dietary consequences, and the food rule is downstream of a broader one about not using animals when an alternative is practicable. That's why a vegan avoiding food is only half the picture. The same logic that keeps dairy off a vegan's plate keeps wool off their back, leather off their feet, silk off their scarves, down out of their jacket, and animal-tested products off their bathroom shelf. It also shapes choices with no dietary equivalent at all: many vegans skip zoos, aquariums, circuses with animal acts, and horse racing, on the same grounds they skip eggs.

This is the most common place the two labels get flattened into synonyms by people who haven't thought about the difference, and it's also the most common source of friction when they're not: a vegetarian who buys leather boots hasn't broken any rule of vegetarianism, because vegetarianism never had a rule about boots. A vegan who buys the same boots has stepped outside their own stated position. Neither is a verdict on the person. It's just what the words were built to cover. For the specific ingredient calls that trip people up, the is it vegan? shelf has verdicts on individual materials and additives, and where vegans draw the line covers the judgment calls that come up once food is settled.

Of every label on this page, “plant-based” is the one that means the least, because no regulator has defined it. The FDA does not regulate the term, and as of its January 2025 draft guidance on labeling plant-based alternatives to animal-derived foods, the agency still treats those products as “non-standardized foods” with no fixed identity standard, recommending only that the label name the plant source, as in “soy chicken” or “pea protein burger.” That draft guidance was open for public comment through May 2025 and had not been finalized as of this writing.

In practice, “plant-based” gets used to mean anything from strict whole-food plant-based diets built around vegetables, grains, legumes and fruit with minimal oil or processed substitutes, to a menu category that just means “the vegan option,” to a marketing word slapped on a product that's mostly oil and starch because it happens to contain no animal ingredient. None of those usages is wrong, because there's no standard to be wrong against. The retail-label version of this problem, including how it interacts with the word “vegan” on packaging, is covered in full in plant-based vs vegan on a label.

The honest answer is that vegan is harder, and the reason is specific rather than general: the two foods vegetarians lean on hardest, dairy and eggs, are exactly the two foods vegan cuts. Cheese, milk, butter and eggs are load-bearing in vegetarian cooking precisely because they're the easiest way to add fat, richness and binding once meat is off the table, which means the vegetarian-to-vegan step removes the ingredients doing the most work in a vegetarian kitchen, not the ones doing the least.

The gap is widest at restaurants. A vegetarian eating out can usually find a pasta with cheese, an omelet, or a dish with butter swapped in without much friction, because most kitchens already cook that way for vegetarian guests. A vegan ordering the same meal has to ask about the stock, the pastry fat, whether the bread contains milk or egg wash, and whether the fryer is shared, and in a lot of restaurants the honest answer to all four questions is inconvenient for the kitchen. Grocery shopping has mostly closed this gap over the past decade thanks to plant milks, egg replacers and vegan cheese, which is why dairy substitutes by function and egg substitutes exist as guides at all. Eating out has not closed nearly as much.

The two big long-running cohorts on this question, the UK's EPIC-Oxford study and the US Adventist Health Study-2, don't agree with each other, which is itself the honest finding. EPIC-Oxford found no significant difference in all-cause mortality between vegans, vegetarians and meat eaters, though vegetarians in that cohort showed a roughly 30 percent lower risk of heart disease. Adventist Health Study-2, drawn from a Seventh-day Adventist population of over 96,000 people recruited between 2002 and 2007, found vegetarians overall had about a 12 percent lower all-cause mortality than non-vegetarians, with vegans in that cohort showing a 16 percent lower cancer risk specifically. Neither study isolates vegan from vegetarian cleanly enough to declare one diet the longevity winner over the other. For the full breakdown of both cohorts, their limitations and what they do and don't show, see plant-based diets and longevity.

Moving from vegetarian to vegan removes a diet's default sources of vitamin B12, and shrinks its easiest sources of vitamin D, iodine, calcium and complete protein, since dairy and eggs had been supplying some or all of those by default without anyone thinking about it. None of this is an argument against the move. It's a checklist. Vitamin B12 in particular is not reliably present in unfortified plant food at all, vegetarian or vegan, which is why it's the one nutrient every major dietetics body flags regardless of which side of this label pair someone lands on. The specific numbers, sources and supplement forms are covered in vitamin B12, and the broader supplement decision is in which supplements are actually needed.

Neither label is a better version of the other; they answer different questions. Someone who wants to eat less meat without changing much else, and isn't troubled by wool or leather, has already picked vegetarian whether they use the word or not. Someone whose objection is to using animals at all, in any form, has picked vegan, and the diet follows from that rather than the other way round. A lot of vegetarians move to vegan gradually, cutting dairy or eggs first for reasons that have nothing to do with morality, cost, allergy, or a skin reaction to whey being common ones, and end up vegan without ever framing it as an ethical leap. That's a normal route in, not a lesser one.

Pescatarian and flexitarian sit outside both categories rather than between them: a pescatarian eats fish while excluding other meat, which the original 1847 Vegetarian Society definition would not have recognized as vegetarian at all, and a flexitarian reduces meat without excluding it, which makes the label closer to a description of habits than a rule. Both are legitimate positions with real health and environmental rationale behind reducing meat, but neither maps onto the vegan/vegetarian split this guide covers, and neither carries the exclusion of non-food animal products that defines veganism. If the reader's question is really about a single ingredient, like whether honey counts, that's answered directly in why vegans don't eat honey rather than here.