33 Gross As Heck Scary Movies That’ll Leave You Feeling Ill

Try using the arrow keys

Horror movies intentionally provoke terror and fear by design, poking at our primal lizard brains to trigger physiological reactions our bodies developed over eons to help us survive. Given that your brain and body think the stakes are life and death, it's understandable that some people don't enjoy watching the genre. But some horror movies do far more than just scare on an adrenal level — part of the full fright spectrum includes dredging up feelings of repulsion, revulsion, and queasiness. These 33 scary movies that may make you sick aren't for the weak of heart or stomach; most are on record as having audience members become ill or need to leave the theater during screenings.

A number of the films on this list use audio to physically mess audiences up — as mentioned, our bodies are wired for survival, and sounds falling below 19 Hz (known as "infrasound") or jarring high-pitched noises (like animals in distress, or women and children screaming) trigger physical reactions of dread and nausea, per Atlas Obscura. According to 1998 research paper called "Ghosts In The Machine" (via Gizmodo), infrasound may even be responsible for ghost sightings.

Other films lean heavily on bodily fluids and gore to trigger the same responses — you don't need a soundtrack to feel sick seeing creatures slithering into wounds or bloody viscera spattered everywhere. But for those brave few who want to wallow in the corporeal, these 33 films are for you.

More Slideshows