The ethics of eating animals: the arguments, answered

Eating meat isn’t a purely personal choice, because animals die for it: a 2021 estimate by the charity research group Animal Charity Evaluators puts the worldwide average at about 105 vertebrates a year per non-vegan, mostly fish.

Nothing about pigs justifies eating them while protecting dogs: pigs feel pain and fear too, as the UK government’s Animal Welfare Committee found in 2025. Which animals count as food is largely cultural habit.

Far fewer farm animals would exist if we stopped eating them, but having bred an animal is a poor reason to kill it, and in the EU a typical fast-growing meat chicken is slaughtered at about 37 days old (EFSA, 2023).

Valuing humans over animals is speciesist when species alone is the reason, the bias Richard Ryder named in 1970. Real differences in ability can matter, but none of them separates every human from every animal.

An animal’s inability to consent doesn’t license harming it: newborns can’t consent either, and the UN Convention on the Rights of the Child (1989) makes a child’s best interests a primary consideration.

Animals needn’t understand death to suffer as they die: 90% of pigs in England and Wales are stunned with CO2 (UK government, 2024), a gas UK advisers say causes pain and fear. A painless death still cuts a life short.

A lion’s diet can’t license ours: lions are obligate carnivores that can’t choose otherwise, while the British Dietetic Association says carefully planned plant-based diets can support healthy living at every age.

Canine teeth are poor evidence we’re built for meat: in apes and monkeys their size mainly tracks male rivalry, and in our lineage male canines had shrunk to near-female size by about 4.5 million years ago (Suwa et al., 2021).

Eating meat is ancient and natural for an omnivore, but neither makes it right, and today’s amount is recent: FAO figures show meat available per person worldwide nearly doubled between 1961 and 2023.

Humans evolved as omnivores and can eat meat, but the US Academy of Nutrition and Dietetics (2025) says a planned vegan diet can be nutritionally adequate for adults. Vegans need B12 from fortified foods or supplements.

Animal farming is not the circle of life: most farmed land animals are chickens, and in the EU a meat chicken is usually killed at about 37 days old, well before it can breed (EFSA, 2023).

Plants almost certainly can’t feel pain, having no neurons or brain, and if they could, eating meat would cause more of it: US livestock return only about 7% of their feed calories as food (Shepon et al., 2016).

Crop deaths are real, but eating meat almost always causes more of them, because farm animals eat crops too: Poore and Nemecek (2018) found a world without animal products would need 19% less arable land.

Vegans draw the line at sentience, and a 2021 review of over 300 studies for the UK government found strong evidence that even crabs and octopuses can feel pain. Doubt about insects leaves cows and pigs inside the line.

Swatting a biting mosquito isn’t vegan hypocrisy, as the Vegan Society’s definition stops at what is practicable. Adult flies and mosquitoes met 6 of 8 pain criteria in a 2022 review, so gentler options come first.

Roadkill and binned meat aren’t vegan food, since the Vegan Society’s definition excludes all animal products from the diet, but eating them pays nobody to breed or kill an animal, the harm veganism exists to prevent.

Vegans aren’t hypocrites for falling short of 100% vegan: the Vegan Society defines veganism as excluding animal exploitation ‘as far as is possible and practicable’, and what goes on the plate is chosen at every meal.

Oysters and mussels aren’t vegan by the Vegan Society’s definition, which excludes shellfish. Whether they feel pain is unresolved: a preliminary 2022 literature scan by Wageningen Marine Research found no direct test.

Indigenous and subsistence diets don’t disprove veganism, which the Vegan Society defines as avoiding animal exploitation only “as far as is possible and practicable”. A hunter’s necessity doesn’t cover supermarket meat.

The Bible allows people to eat meat, but the chapter of Genesis that gives humans dominion gives them only plants to eat (1:29), and the Catholic Catechism calls needless animal suffering contrary to human dignity.

Few religious rules require eating meat: Islam’s main sacrifice, qurbani, falls at one festival a year, and in a Pew Research Center survey of India (2021), 44% of Hindus said they were vegetarian.

One person going vegan does make a difference: the charity research group Animal Charity Evaluators estimated in 2021 that a plant-based person accounts for about 105 fewer vertebrates killed a year.

If everyone went vegan, farm animals would not be set loose: farmers would breed fewer as demand fell, and the land animals slaughtered for meat, at least 86 billion in 2024 on FAO figures, would dwindle.

Animal farming is no small problem: more than 86 billion land animals were slaughtered for meat in 2024, on UN Food and Agriculture Organization figures. Eating differently needn’t take time or money from other causes.

Farm breeds would dwindle in a vegan world and some could be lost, but eating meat on today’s scale hasn’t stopped them dying out: the UN’s FAO found 63% of local breeds with a known status at risk of extinction in 2025.