Wouldn't say it scares me, but body horror disturbs me. But not all body horror, mostly the kind of body horror, where someone's being turned into something else against their own will by any means. Bonus points to being disturbed if the process cannot be reversed.
I can't help but feel sorry for such characters. Especially if the end result is something like in "I have no mouth and I must scream" or "Made in the Abyss". Like even for the villain it's a bit too much of a punishment... xD
Also I guess it's more related to games than movies, but there's this specific type of jumpscare that just keeps on going. 99,99% of time it's just overdone regular jumpscare, where someone thinks loudness=scariness, but I've stumbled upon that 00,01% that actually scared me. Not because it was loud and "omg hyperrealistic blood and guts!!!!!1111", but like... Weird and cryptic. xD