You’ve got to admire the consistency of science: proving lobsters might be tortured when we cook them by, in part, torturing them first. It’s grim, but the goal is noble: to understand what these animals actually experience before we drop them into boiling water and call it dinner.

A new study on Norway lobsters, published in Scientific Reports, found that common human painkillers significantly altered how the animals reacted to harmful stimuli. This matters because there’s long been a debate as to whether lobsters feel pain at all.

Researchers exposed lobsters to mild electric shocks, which triggered a rapid tail-flapping response, indicating that the lobsters were trying to escape. But when the lobsters were given analgesics like aspirin or lidocaine beforehand, that reaction was reduced or didn’t even happen at all.

Scientists Keep Zapping Lobsters for a Reason That’s Less Evil Than It Sounds

This is one of those moments when the absence of a reaction is itself quite telling. You can ask the lobster how it feels. Believe me, I’ve tried. So, researchers rely on proxy indicators, like behavior, the release of stress chemicals, and nervous system activity. In this case, the lobster’s internal chemistry and gene activity responded in ways consistent with stress and harm.

The fact that drugs designed to dampen pain responses in humans had the exact same effect in the lobsters suggests there’s some kind of biological overlap that humans who spent decades, if not centuries, convincing themselves that it’s fine to eat a lobster because the dumb thing doesn’t even know was going on might actually have to face the fact that they have been inflicting pain on a thing that can in fact feel pain.

Some parts of the world have already recognized that crustaceans experience pain. The UK, for instance, recognizes crustaceans, such as crabs and octopuses, as sentient, and in some parts of the world, these sentient creatures cannot be boiled alive.

This is going to stop almost no one from eating lobster, but it does complicate things for people who want to believe their quest for opulence and pleasure isn’t harming anyone or anything, not even a dumb lobster.