In the Alien series, specifically Prometheus and Alien: Covenant movies, I don’t remember the alien creatures eating anything or their food regimen being mentioned. They're stubborn and angry creatures that just know how to attack, hunt, and lay eggs in order to multiply as many as they can, building a great den and colony in dark, dirty, and remote places.
I’m sure I didn’t see any scene about the Xenomorph eating human flesh in the movies, so how do they survive and live while they’re very active predators? Shouldn't they eat the meat of every kind of prey? They're big and need a lot of food for their metabolism. They have sharp teeth like carnivores. Isn't this proof that they use them for eating and chewing meat and flesh?