Pescetarianism

Lore & Background

The first vegetarians in written Western history may have been the Pythagoreans, though some biographers suspect Pythagoras himself may have eaten fish, making him a pescetarian by today's standards. In Plato's ideal republic, a healthy diet included cereals, seeds, beans, fruit, milk, and honey—but notably not fish, as fish is absent from the relevant passage. Several orders of medieval European monks restricted or banned meat for ascetic reasons but not fish, making them pescetarians. Marcion of Sinope and his followers ate fish but no fowl or red meat. The 'Hearers' of Manichaeism lived on fish, grain, and vegetables. The Rule of Saint Benedict required total abstinence from four-footed animals except for the sick, allowing fish, eggs, and dairy. Benedictine monk Walafrid Strabo wrote, 'Some salt, bread, leeks, fish and wine; that is our menu.' Carthusians and Cistercians also followed fish-based diets. In the 19th century, Francis William Newman, former President of the Vegetarian Society, advocated for a fish-inclusive vegetarian diet in the 1870s and 1880s, arguing that fish do not waste land, reproduce plentifully, do not care for their young in the same way as mammals, and can be killed with minimal pain.

Reader's Guide

Pescetarianism matters as a dietary practice that bridges vegetarianism and omnivory, often adopted for ethical, environmental, or health reasons. The article notes that pescetarianism may be perceived as more ethical because fish may not experience pain like mammals, though scientific evidence shows fish have pain receptors and can feel pain—an ongoing debate. A Japanese study in 2018 suggested a pescetarian diet could reduce the food-nitrogen footprint. Globally, pescetarianism increased in popularity in the mid-to-late 2010s, with 40% of pescetarians having adhered for more than a couple years. It is more popular among women than men in all regions with available data. The diet is also recognized as plant-based and associated with reduced red meat consumption, which may promote health.

Did You Know?

• Francis William Newman, former President of the Vegetarian Society, advocated for a fish-inclusive vegetarian diet in the 1870s and 1880s, arguing fish do not care for their young in the same way as mammals and can be ki

The Name and Its Origins

The word "pescetarian" is a relatively young coinage, born in the United Kingdom during the late 1980s as a blend of two linguistic traditions. It fuses the Italian word "pesce," meaning fish, with the English word "vegetarian," creating a single term that immediately signals a diet centered on seafood while excluding other meat. The pronunciation, typically rendered as PESK-ə-TAIR-ee-ə-niz-əm, reflects its hybrid heritage. An alternate spelling, "pescatarianism," occasionally appears in informal usage. In more formal or academic contexts, the compound "pesco-vegetarian" has served as a synonym, surfacing in American publications and scholarly literature since at least 1980. Despite the term's late arrival in everyday vocabulary, the dietary pattern it describes is far older. The neologism simply gave a name to a practice that had already been followed, in various forms, across multiple civilizations and centuries. The brevity of the word—just two roots stitched together—mirrors the simplicity of the dietary rule it encodes: fish and seafood replace all other animal flesh, while eggs and dairy remain permissible additions.

Ancient and Medieval Precedents

Long before the word existed, the dietary pattern we now call pescetarianism appeared repeatedly across cultures. In ancient Greece, some biographers suspect Pythagoras himself may have permitted fish alongside his otherwise meatless teachings, and Plato's vision of an ideal republic explicitly included fish alongside cereals, seeds, beans, fruit, milk, and honey. In Japan, Emperor Tenmu's 675 edict banned livestock and wild animal consumption under Buddhist influence, yet by 737 Emperor Shōmu had authorized the eating of fish and shellfish, establishing a pattern that persisted for roughly twelve centuries. In medieval Europe, numerous monastic orders—Benedictines, Carthusians, Cistercians—restricted four-footed meat while freely incorporating fish, eggs, and dairy into daily meals. The Carthusians went further, limiting Fridays to bread and water. England's anchorites subsisted on fish seasoned with apples and herbs, legume soups, and dairy. The Marcionites of the early Christian era regarded fish as a holier food than fowl or red meat, while Manichaean "Hearers" consumed fish, grain, and vegetables, believing aquatic life was free from the taint of sexual reproduction.

Modern Adoption and Global Reach

The twentieth century brought pescetarianism into organized dietary discourse. Francis William Newman, who led the Vegetarian Society from 1873 to 1883, created an associate membership category specifically for those who ate fish but no other meat. By the 1890s, Newman himself had transitioned to a pescetarian diet, arguing that fish occupied no land space, reproduced prolifically, lacked parental attachment to their young, and could be harvested with minimal suffering. In the twenty-first century, the diet has gained visibility alongside broader plant-based trends. A 2016 book titled Seagan Eating promoted a seafood-centered diet that further discouraged dairy and eggs. Surveys from 2017 to 2018, including Ipsos MORI and GlobalData, consistently placed global pescetarianism at roughly three percent of adults. In the United Kingdom, a 2018 poll of two thousand adults found about four percent identified as pescetarian, while a 2021 survey placed the figure at three percent. Notably, the diet skews female across all regions where sex-disaggregated data exist, and many adherents cite environmental concerns about reducing red and processed meat consumption.

Ethical and Theological Rationales

The justifications for choosing fish over other meats have varied across eras and traditions, yet several recurring themes emerge. The Manichaeans offered a theological argument: because fish are born in water and reproduce without sexual connection, they are free from the moral pollution they attributed to land animals. This made fish ethically acceptable within a framework that otherwise forbade all animal flesh. In medieval monastic life, the Rule of Saint Benedict permitted fish as a practical alternative to four-footed meat, with the exception carved out for the sick. Paul the Deacon confirmed that cheese, eggs, and fish formed the ordinary monastic diet, while Walafrid Strabo wryly summarized a monk's menu as salt, bread, leeks, fish, and wine. In the modern era, Francis William Newman's rationale was more utilitarian: fish do not consume arable land, reproduce at high rates, show no parental bonding, and can be caught and killed with comparatively little pain. More recently, environmental motivations have driven many to swap red and processed meats for seafood and plant foods, framing pescetarianism as a lower-impact dietary choice.